Executive Summary
- A careful history should include the presence of fever and any febrile patterns. Some infections have characteristic fever patterns: the “tertian fever” of Plasmodium vivax malaria recurring every 48 hours or the constant “step ladder” crescendoing fever of typhoid fever.
- On physical exam, evidence of bruising or petechiae should be sought because they might indicate a hemorrhagic complication of infection, such as dengue hemorrhagic fever or disseminated intravascular coagulation. A head, eyes, ears, nose, and throat (HEENT) examination is focused on identifying indicators of focal HEENT infection, such as otitis media, pharyngitis, or the stigmata of systemic infections, including typhoid (coated or “furry” tongue) or Koplik spots (bluish-white spots on the buccal mucosa) in measles.
- In febrile children with evidence of critical illness (significant non-fever-related vital sign abnormalities or derangements of consciousness, perfusion, or respiration), broad-spectrum antimicrobial coverage should be considered. In a completely undifferentiated patient, this initially would include coverage for most common gram-positive and gram-negative bacterial species. Abdominal pain or significant gastrointestinal complaints should prompt consideration of anaerobic coverage as well. Some common considerations include ampicillin/gentamicin or cefepime/piperacillin-tazobactam. In patients with a history of immunocompromise, hospitalization, or consideration of resistant organisms (methicillin-resistant Staphylococcus aureus or resistant gram-negative bacteria), agents such as vancomycin and/or meropenem should be considered.
- Several multiplex polymerase chain reaction (PCR) tests have been developed specifically for assessing fever or severe illness in patients who have returned from travel. Several commercially available tests, including the Biofire Tropical Fever Panel, the Biofire Global Fever Panel, the MedGenome Tropical Fever Panel, and the Viasure Tropical Fever Panel, are in common usage. While these tests are becoming increasingly available in large commercial laboratories and medical centers, their expense can limit their utility, and no single test exists that tests for the complete range of tropical pathogens.
- Malaria is a parasitic disease caused by Plasmodium species, the most important being Plasmodium falciparum, P. vivax, Plasmodium ovale, Plasmodium malariae, and the zoonotic Plasmodium knowlesi. Among these, P. falciparum is the most dangerous and is responsible for the majority of severe disease and deaths worldwide, whereas P. vivax is notable for its ability to remain dormant in the liver as hypnozoites and cause relapses months or years after the initial infection. Malaria primarily affects tropical and subtropical regions, with the highest burden in sub-Saharan Africa, but significant cases also occur in South Asia, Southeast Asia, and parts of Latin America.
- Acute human immunodeficiency virus (HIV) infection often presents as a nonspecific “mononucleosis-like” illness two to four weeks after exposure. Common symptoms include fever, sore throat, lymph node enlargement, rash, headache, and muscle or joint pain. Some individuals may have diarrhea or neurologic symptoms, while others remain asymptomatic. These signs usually resolve spontaneously within one to two weeks, which can lead to missed or delayed diagnosis. Because antibody tests still may be negative in this early window period, detection relies on antigen/antibody combination assays or PCR to identify viral ribonucleic acid. Early diagnosis of acute HIV infection is critical, since prompt initiation of antiretroviral therapy reduces viral replication, preserves immune function, and markedly decreases the risk of transmission to others.
- Mpox (monkeypox) is a zoonotic viral infection that is contracted after close physical contact with either an infected person or an infected animal (generally rodents or primates). Congenital mpox has been described. Clinical features often begin with prodromal symptoms, such as fever, chills, lymphadenopathy, headache, myalgia, and fatigue. Within a few days, a characteristic rash develops, typically progressing from macules to papules, vesicles, pustules, and scabs. Lesions often are well-circumscribed, deep-seated, and can be painful. Unlike varicella, lymphadenopathy is a distinguishing feature. The rash can be localized or disseminated, commonly involving the face, extremities, and mucous membranes, including genital and perianal sites in recent outbreaks. Diagnosis is confirmed by PCR testing of skin lesion scrapes.
Every year, a significant number of families travel internationally with children, who then have a high rate of febrile illness after returning home. While most travel-acquired infections are self-limited and mild, some diseases may rapidly become fatal, and early recognition and aggressive management can maximize the child’s outcome. This review presents a focused clinical approach to caring for a child returning from international travel with a fever.
— Ann M. Dietrich, MD, FAAP, FACEP, Editor
By Joseph U. Becker, MD
Introduction
Global travel continues to increase year after year, with some estimates suggesting that more than 1 billion individuals now travel for tourism yearly, including more than 60 million children.1 The number of Americans traveling abroad, including families, has increased in 2022 and 2023, totaling more than 67 million persons, up from the COVID-19 pandemic-suppressed travel numbers of 2020 and 2021.1-3 While vaccination, appropriate hygiene, insect avoidance strategies, pre-travel health counseling, and prophylactic medication regimens can reduce the risk of acquired infections, many travelers develop febrile illness either while traveling or upon return to their home country. Indeed, among travelers returning from developing and newly developed countries, the rates of febrile illness have been reported to vary between 43% and 79%.4,5 Of these travelers, those traveling to visit family seem to be at even higher risk for febrile illness.4,5 Surveillance data indicate that 8% to 15% of travelers returning from low-income regions seek medical care for illness — often because of fever — and among those presenting with febrile illness, approximately 26% require hospitalization.6 Furthermore, recently arrived immigrants and refugees to the United States may arrive with febrile illnesses acquired either in their nation of origin or during travel. Substantial numbers of these individuals are traveling from or through areas with poor healthcare infrastructure, public health institutions, and disease surveillance and may not have access to healthcare resources along the way.7
Fever in the child returning from travel can be a challenging presenting complaint in the emergency department. Differential diagnostic considerations may be broad and heavily dependent on regionally, seasonally and temporally variable disease ecology, and epidemiology. While most travel-acquired infections are self-limiting and mild, pathogens that may rapidly produce critical illness and even death must be considered. Furthermore, antimicrobial resistance patterns are region- and organism-specific, and standard therapies used in the United States for common infectious conditions may be inappropriate for infections acquired abroad. Additionally, depending on the specific case, pathogens that have the potential for human-to-human epidemic spread in the United States may be on the differential diagnosis. Recent headlines have been filled with sudden, regional outbreaks of disease, including Marburg virus in Rwanda (October 2024), Ebola virus in Uganda (September 2022), and dengue virus outbreaks ongoing in many nations in the western hemisphere (summer/fall 2024). Lastly, increasing numbers of children undergoing treatment with chronic immunomodulatory medications mean that pediatric populations, already at somewhat elevated susceptibility to some infectious diseases, may be even more at risk for acquiring or developing severe manifestations of such an infection.
It is critically important that clinicians treating children who have returned from international travel with a febrile illness adopt a systematic approach to generating a comprehensive (but not alarmist) range of differential diagnostic considerations and tailor and prioritize diagnostic and clinical work-up to rapidly identify concerning clinical signs and conditions. This review will present a focused clinical approach to the management of children returning from international travel with fever. It will discuss management priorities and provide background on diagnoses of import based on their incidence or the potential for severe disease and also will discuss commonly available diagnostic products and resources that may be of assistance to the emergency clinician caring for these patients.
Background
After the coronavirus pandemic of 2020-2021, global travel and tourism economies have seen significant rebounds, with many regions now reaching or surpassing pre-pandemic travel levels.8 Regions such as the Middle East, Southeast Asia, and East Africa have seen tourism numbers at or near their 2019 levels, in some cases setting new records for revenue and traveler volume.8 Additionally, there is a growing novelty for travel, including family travel to less-developed destinations and destinations not previously associated with tourism, such as regions with recent conflict or instability whose health infrastructure might be recovering or inadequate.9 While pre-travel counselling can be helpful in informing travelers of regions with ongoing disease outbreaks and identifying effective prevention strategies, studies show that only a third of travelers seek out pre-travel counselling prior to international travel.10 Furthermore, all this travel is occurring in a background of increasing rates of arboviral transmission, including dengue and chikungunya viruses, as well as extremely contagious and persistently present diarrheal illnesses in many parts of the world. The realities of travel (with crowded airports, public transportation, and outdoor activities) mean that many international travelers have significant risk of exposure to multiple pathogens of clinical or even epidemic importance.
This review will focus on children returning from international travel with a febrile illness. While the presence of a fever is highly suggestive of an ongoing infectious process, fever may not always be present in the acutely infected child. While the absence of fever in an ill child does not preclude infection, it does require a broadening of the diagnostic considerations to include non-infectious causes. Importantly, there are dozens of case reports and articles in the literature of travelers suffering significant injury or even dying as a result of accidental ingestions of toxic substances, including cyanide and toxic alcohols (e.g., methanol).10 While these events are rare occurrences, febrile illness after international travel is incredibly common and requires a systematic approach to avoid missing potentially serious or contagious conditions.
Approach Considerations: History
As with any patient presenting for care at an emergency department, an initial approach should focus on identifying life-threatening illness. As is relevant, a tailored approach focusing on mental status; hydration; respiratory effort; airway, breathing, and circulation (ABC); and vital signs should direct both initial resuscitative actions and diagnostic work-up. A stooling and urination history (how many wet diapers, etc.) should be obtained.
Once patient stability has been confirmed, the initial approach to the febrile child returning from international travel should be rooted in the history. A broad and detailed travel history should be obtained, going back at least three months. While the majority of infections acquired during travel have relatively short incubation periods (measured from days to up to three weeks), some pathogens are notorious for their ability to cause fever and significant illness months or even years after initial infection. (See Table 1.) For example, the incubation period for most common circulating variants of influenza is one to four days, with the majority of individuals becoming symptomatic on day 2.15 Norovirus, an incredibly common and contagious cause of diarrhea and vomiting, has an incubation period ranging from six to 48 hours.16 However, other culprits may cause severe disease months after return. Plasmodium vivax and Plasmodium ovale, two species of malaria, are known for their ability to form a dormant hypnozoite phase, which evades immune response by hiding out intracellularly in hepatocytes. The severe fever and chills commonly associated with malaria infection may not immediately occur, and symptoms might not manifest until weeks or months later, when the hypnozoites emerge to cause symptomatic malaria.11 These symptoms might be even more suppressed in the setting of incomplete malaria chemoprophylaxis. Similarly, other pathogens may have long incubation periods, in the case of mononucleosis lasting as long as a month.
Table 1. Common Infections and Their Incubation |
Influenza Virus (A/B)
Norovirus
Adenovirus
Ebola Virus Disease
Marburg Virus Disease
Dengue Virus
Epstein-Barr Virus (Mononucleosis)
Typhoid Fever
Acute Human Immunodeficiency Virus Infection
Plasmodium vivax Malaria
Plasmodium falciparum Malaria
Mpox (Monkeypox)
|
Detailed travel histories should include countries visited as well as specific regions, since infectious disease ecology may vary dramatically between rural and urban areas or between high- or low-altitude areas within the same country. Furthermore, isolated outbreaks may mean that otherwise safe countries may, at times, be higher risk for outbreaks. The characteristics of traveler accommodations during the stay should be obtained as well, since official tourist destinations are associated with lower rates of infection from endemic diseases than those travelers staying with family, particularly outside of urban areas.17
The history also should focus on activities and potential exposures during travel, such as contact with fresh water sources (lakes or streams) and contact with either wild or domesticated animals. Bites or scratches from either wild or domesticated animals might be reported by either the patient or their parents, but this should be directly investigated because children may not always alert their parents to these exposures. A table of environmental or animal contacts and the potential disease transmission noted is provided in Table 2.
Table 2. Animal Exposures and Common or Associated Infectious Diseases11-14 |
Dogs, Cats, Bats, Raccoons, Foxes
Rabbits, Rodents
Farm Animals
Birds
Reptiles and Amphibians
Monkeys/Non-Human Primates
Fish/Shellfish
Camels
Fruit Bats
Bushmeat
Freshwater
|
A history of arthropod or insect exposure and bites also should be elicited. Patients should be asked about their strategy for malaria prophylaxis, if it is relevant to the region visited, as well as general insect avoidance strategies, such as repellant, clothing, or bednets. If a patient was prescribed malaria prophylaxis for their travel, an accurate history of their adherence to the prophylactic regimen should be obtained, including medication usage both before leaving for and after return from travel. Clinicians also should directly verify that the regimen that a traveler used for a particular region is appropriate and effective, since resistance patterns or altered travel itineraries may result in inadequate protection.
A history of social interactions should be obtained. Was there contact with large gatherings or individuals who have since been known to have developed illness? In the case of adolescent travelers, a history of sexual encounters should be obtained, including the number of partners, the type and frequency of physical or sexual interactions, and if barrier protection, such as condoms, were used.
Lastly, a detailed history of patient symptoms, including their onset, should be obtained. Fever course and duration should be noted, since some infections have characteristic fever patterns (the “tertian fever” of P. vivax malaria recurring every 48 hours or the constant “step ladder” crescendoing fever of typhoid fever). Rashes should be noted and their distribution, character, and associated symptoms (itching, pain) should be described. Other symptoms, such as lymphadenopathy, dysuria, or vaginal or penile discharge, as well as the presence of even mild respiratory or gastrointestinal (GI) symptoms should be assessed.
The history may provide key insights into the potential range of infectious considerations in a particular patient, but it is important to recall that infections may not manifest their typical symptom profiles in every patient. It also is important to keep in mind that patients may have more than one process ongoing simultaneously. Indeed, given the high incidence of diarrheal and respiratory illness acquired during travel, it is important to consider co-infections, since these common symptoms may mask or confuse the symptoms related to another, potentially more serious infectious process. There are case reports in the literature of missed malaria diagnoses in febrile travelers because of the presence of diarrhea, which the clinician assumed was indicative of the presence of an uncomplicated GI infection.18
Approach Considerations: Physical Examination
As with any patient presenting to the emergency department, an initial physical evaluation should focus on vital signs, ABCs, and identifying critical illness. This evaluation should focus on indicators of perfusion and hydration, such as capillary refill, skin turgor, fontanelle profile, mucous membranes, as well as overall appearance and responsiveness (see immediate management of critical illness section). Assessing peripheral extremity perfusion also can assist in differentiating between septic and hypovolemic shock. While a comprehensive discussion of all physical examination findings associated with various infectious processes is beyond the scope of this review, the following is a brief discussion of important questions to address during the physical assessment. See Table 3 for a selected list of physical exam findings associated with specific pathogens of importance.
Table 3. Physical Examination Findings of Importance in Children Returning from Travel14,17,32,34 |
Plasmodium vivax or Plasmodium falciparum Malaria
Dengue Virus
Chikungunya Virus
Zika Virus
Yellow Fever
Typhoid Fever
Leptospirosis
Rickettsial Infections
Schistosomiasis (Acute Katayama Fever)
Visceral Leishmaniasis (Kala-Azar)
Cuteaneous Leishmaniasis
Ebola/Marburg Viruses
Lassa Fever
Anthrax (Cutaneous)
Rabies
Amebic Liver Abscess
|
Focused but thorough examinations of critical organ systems should be undertaken. A focused neurologic examination should be performed, identifying focal neurologic symptoms, indicators of meningeal inflammation or increased intracranial pressure, and mental status. The cardiac examination should focus on the presence of murmurs or abnormal heart sounds, such as a pericardial friction rub, as might be appreciated in cases of pericarditis/pericardial effusion. The pulmonary examination first should identify respiratory distress, evidenced by increased work of breathing, nasal flaring, retractions, the use of accessory muscles, and/or tachypnea. The pulmonary examination also should identify focal abnormalities in the examination of the lung fields, which may indicate the presence of a pleural effusion or a focal lobar process. The abdominal examination should identify point tenderness, localizing either to individual quadrants or the flanks. Attention should be paid to indicators of peritonitis, such as rebound pain or pain that worsens with or prevents movement or ambulation. A vaginal or penile/testicular examination should be considered on all patients, particularly if there is concern for genitourinary or sexually transmitted infections. An integumentary examination should identify any rashes or skin or nail infections, even if faint or subtle and not identified by the patient. Evidence of bruising or petechiae should be sought because this might indicate a hemorrhagic complication of infection, such as dengue hemorrhagic fever or disseminated intravascular coagulation (DIC). A head, eyes, ears, nose, and throat (HEENT) examination is focused on indicators of focal HEENT infection, such as otitis media, pharyngitis, or the stigmata of systemic infections, including typhoid (coated or “furry” tongue) or Koplik spots (bluish-white spots on the buccal mucosa) in measles. An examination of the lymphatic system should identify lymphadenopathy, and the distribution of swollen nodes should be noted.
Management of Critical Illness
The management of critical illness in children returning from international travel should proceed as it would for any child. The initial focus should be on ABCs, perfusion, and correcting vital sign abnormalities. The presence of shock should be ascertained both by laboratory analysis, including indicators of impaired perfusion, and elevations of creatinine or transaminases. Shock must be differentiated, since hypovolemic and septic shock may contribute to impaired organ perfusion, particularly in patients with diarrhea, vomiting, and/or anorexia. Adequate bore intravascular access should be obtained immediately in cases of suspected shock. Intravenous access initially may not be possible in patients with significant dehydration and/or peripheral vascular constriction, and intraosseous access may be required. Intraosseous lines have the advantage of being useful in a variety of settings, including in the initial resuscitation of acutely dehydrated and septic patients and for collecting a variety of diagnostic tests (lactic acid tests, etc.).
Many cases of septic shock presenting to the emergency department will have a component of hypovolemia. This may be because of periods of anorexia prior to presentation, volume losses (diarrhea), vomiting, or increased insensible losses, such as in patients with fever. These effects can be further exacerbated by the capillary leak that is characteristic of septic shock. An assessment of volume status as described earlier in the Physical Examination section of this review may help determine the degree of hypovolemia. Modalities such as bedside ultrasound examination of the inferior vena cava may yield further detail. Initial resuscitation with boluses (20 mg/kg) of crystalloid solutions should be undertaken, and administration of broad-spectrum antimicrobials should be prioritized.
Initial Empiric Therapy
In febrile children with evidence of critical illness (significant non-fever-related vital sign abnormalities or derangements of consciousness, perfusion, or respiration) broad-spectrum antimicrobial coverage should be considered. In a completely undifferentiated patient, this initially would include coverage for most common gram-positive and gram-negative bacterial species. Abdominal pain or significant gastrointestinal complaints should prompt consideration of anaerobic coverage as well. Some common considerations include ampicillin/gentamicin or cefepime/piperacillin-tazobactam. In patients with a history of immunocompromise, hospitalization, or resistant organisms (methicillin-resistant Staphylococcus aureus or resistant gram-negative bacteria), agents such as vancomycin and/or meropenem should be considered.12,19
The travel history, symptoms, and examination often can provide some guidance as to how to best tailor initial empiric therapies, but the overall goal is to cover all likely culprit pathogens while the child is being resuscitated. Empiric therapy for malaria is not frequently administered, usually because malaria rapid diagnostic tests (RDTs) and even malaria polymerase chain reaction (PCR) generally can be obtained within hours in many U.S. medical centers. Likewise, empiric therapy with broad-spectrum antifungal agents generally is not considered unless a patient has significant immunocompromise. Empiric antiviral treatment with acyclovir or valacyclovir for herpes simplex virus (HSV) generally is not considered in all but neonates unless a component of the history (immunocompromise), examination (vesicular rash), or work-up (imaging or cerebrospinal fluid [CSF]) suggests this as a potential cause.
Important Diagnostic Tools
Many of the diagnostic tests of importance in working up febrile children returning from travel are standard tests that are used every day in pediatric emergency departments. This discussion will focus on diagnostic tools of specific utility in the context of those patients while excluding in-depth coverage of common laboratory testing, including the complete blood count, inflammatory markers, blood cultures, urine, CSF, or imaging, such as chest X-ray, computed tomography (CT) scanning, or magnetic resonance imaging.
Multiplex PCR Panels
PCR identifies and amplifies the genetic material of a parasite, bacteria, or virus, allowing rapid diagnosis as well as potentially yielding further clinically relevant data, such as speciation, subgroup identification, or the presence of markers of antimicrobial resistance. Multiplex PCR panels are PCR tests that are capable of identifying the presence of multiple different pathogens simultaneously. These tests saw their first clinical use in 2008 with panels designed for the diagnosis of respiratory pathogens, but multiplex PCR panels recently have become available for identifying a wide array of infectious agents. These panels offer significant clinical benefit because they can rapidly identify a wide range of possible pathogens with a single sample. Multiplex PCR panels are highly sensitive and can be run in less than an hour. Several multiplex PCR tests have been developed specifically for assessing fever or severe illness in patients who have returned from travel. Several commercially available tests, including the Biofire Tropical Fever Panel, the Biofire Global Fever Panel, the MedGenome Tropical Fever Panel, and the Viasure Tropical Fever Panel, are in common usage. While these tests are becoming increasingly available in large commercial laboratories and medical centers, their expense can limit their utility, and no single test exists that tests for the complete range of tropical pathogens.20,21
Respiratory PCR Panels
PCR for the diagnosis of respiratory pathogens remains a tool of critical importance for differentiating respiratory infections, particularly during the winter virus season, and for identifying patients who potentially would benefit from virus-specific antiviral agents. These tests also may be of benefit in the work-up of febrile individuals returning from travel. Viral respiratory infections are some of the most common causes of fever in returning travelers.1,4,5 However, many patients with respiratory virus infections may have limited or delayed respiratory symptoms. Viruses such as influenza are notorious for their non-respiratory symptoms, including fever, malaise, myalgias, and nausea/vomiting, making initial identification of the respiratory infection challenging. Furthermore, many respiratory infections may produce fever as an early symptom prior to the development of the associated respiratory symptoms. And lastly, respiratory infections may produce symptoms of varying severity because of the presence of comorbid respiratory disease or factors, such as tobacco use or the presence of asthma.
The development of multipex PCR panels for respiratory viruses has greatly assisted in the diagnosis of respiratory disease. Given the significant overlap in the symptomology of these disease processes, it would be difficult, if not impossible, to otherwise differentiate clinically between most respiratory viruses. While most respiratory infections produce self-limited infections without need for clinical intervention, efficacious treatments exist for several pathogens, including COVID-19, influenza, and Mycoplasma pneumoniae, making their diagnosis useful, particularly early in the course of infection. Currently, there are multiple multiplex PCR panels available for respiratory pathogens.20-23 While these tests are of significant clinical usefulness, their employment is limited by their cost and availability.
Stool PCR Panels
A significant proportion of travelers returning from international travel experience diarrhea. Travel-related diarrhea may not even be infectious in origin, and even when it is, it frequently does not produce fever or systemic illness. However, several intestinal pathogens can produce significant symptoms and even critical illness, particularly in the very young or the immunocompromised. In these patients, clinicians must maintain a wide differential diagnosis, since many infectious processes that would produce either no or mild disease in immunocompetent or older individuals must be suspected in infants, young children, and those with impaired immune function. The presence of diarrhea should not preclude further evaluation for non-intestinal pathogens as potential causes of fever or systemic illness. Because diarrheal disease is so common after travel, it often is assumed to explain a child’s fever when, in fact, a more serious underlying infection may be present.
Traditionally, the diagnosis of intestinal pathogens relied heavily on stool culture and microscopy, with skilled technicians and specific equipment needed to identify pathogens or their ova. This approach was limited by the long turnaround time — cultures often required several days and frequently failed to distinguish true pathogens from colonizers. Similarly, accurate microscopy depended on trained personnel, who were not always available, particularly in smaller health facilities. Given limitations with sample preparation as well as organism reproductive cycles, these tests also suffered from low sensitivity, often requiring multiple examinations over the course of days to definitively exclude infection.19,20,23,24
In recent years, multiplex gastrointestinal PCR panels also have become available, allowing for the rapid diagnosis of multiple intestinal pathogens, including bacteria, viruses, and parasites, from a single stool sample.20-23 Similar to other multiplex PCR panels, these tests are costly, may not be offered at all clinical labs, and may not be appropriate for patients with mild symptoms that likely will resolve without treatment.
Malaria Testing
For patients who have traveled to malarial regions, testing for malaria parasites should be prioritized, given the potential life-threatening nature of this infection. Traditionally, malaria testing has relied on microscopy, with skilled and experienced microscopists being required to identify and speciate malaria parasites on thick and thin blood smears. This approach was time-consuming because even at large medical centers, appropriately trained individuals are hard to come by, leading to delays in testing and diagnosis.25,26
In the 1990s, malaria RDTs first were introduced, but these early tests suffered from inconsistent performance and inadequate sensitivity.27,28 However, in recent years, multiple malaria RDTs (largely relying on lateral flow immunochromatography targeting Plasmodium-specific antigens) have become commercially available, dramatically improving the ease of diagnosis of malaria. While the sensitivity of malaria RDTs has improved significantly over the years, current tests sometimes are unable to detect very low levels of parasitemia, which can be seen in infections with non-Plasmodium falciparum malaria. Furthermore, commercially available malaria RDTs are able to speciate P. falciparum malaria only from the other species of malaria (P. vivax, P. ovale, Plasmodium malariae, and Plasmodium knowlesi). Knowledge of malaria parasite ecology in the region of travel, as well as the severity of illness (P. falciparum is by far the most common cause of malaria-related severe illness and death) usually allows for appropriate treatment decisions to be made on the basis of a positive RDT, even without full speciation.27,28
Malaria testing using PCR, as performed in the multiplex PCR panels discussed, also is becoming more commercially available and is highly sensitive for detecting malaria infection. While PCR testing generally is more time-consuming than malaria RDTs, it is becoming increasingly available, particularly at major laboratories and larger, academic medical centers. Malaria PCR testing can be useful when RDTs fail to identify low levels of parasitemia or when RDTs are unable to fully speciate the malaria parasite identified. PCR also can be helpful in identifying the presence of multiple concurrent malaria parasites in a given sample, which would potentially be difficult to determine with RDT testing alone.27,29 Although PCR testing often can be done rapidly (many of the panels described boast turnaround times of less than one hour), many labs perform a malaria RDT for near immediate response while awaiting the result of the multiplex PCR panel for confirmation, speciation, and detection of potentially missed infections.
Selected Pathogens of Import
Most febrile travelers will be afflicted with common pathogens, including influenza, common respiratory viruses, such as adenovirus or rhinovirus, or diarrheal illnesses, including norovirus, Escherichia coli, or Salmonella spp.1,4-6 This review will briefly cover the conditions and pathogens of importance in working up febrile child travelers.
Malaria
Malaria is a parasitic disease caused by Plasmodium species, the most important being P. falciparum, P. vivax, P. ovale, P. malariae, and the zoonotic P. knowlesi. Among these, P. falciparum is the most dangerous and is responsible for the majority of severe disease and deaths worldwide, whereas P. vivax is notable for its ability to remain dormant in the liver as hypnozoites and cause relapses months or years after the initial infection. Malaria primarily affects tropical and subtropical regions, with the highest burden in sub-Saharan Africa, but significant cases also occur in South Asia, Southeast Asia, and parts of Latin America.
Transmission occurs through the bite of female Anopheles mosquitoes, which inject sporozoites into the human bloodstream while feeding. Cyclical destruction of infected red cells leads to the hallmark symptoms of malaria — fever, chills, sweats, headache, and anemia. Severe malaria, most often caused by P. falciparum, can progress rapidly to life-threatening complications such as cerebral malaria, severe anemia, respiratory distress, or multiorgan failure if not treated promptly.11,30
Prevention focuses on reducing exposure to mosquito bites through insecticide-treated bed nets, insecticide spraying, and environmental measures to limit mosquito breeding. Chemoprophylaxis with antimalarial drugs is recommended for travelers to endemic areas. The Centers for Disease Control and Prevention (CDC) as well as the World Health Organization (WHO) provide updated, regionally tailored chemoprophylaxis regimens for malaria. Antimalaria treatment depends on the infecting species and local drug resistance patterns. Again, the CDC and WHO both maintain updated maps of malaria species ranges as well as resistance patterns. For P. falciparum, artemisinin-based combination therapies (ACTs) are the standard of care, while chloroquine remains effective for sensitive P. vivax or P. ovale infections. In addition, P. vivax and P. ovale require primaquine or tafenoquine to eradicate dormant liver forms and prevent relapse. Prompt diagnosis and treatment, coupled with preventive measures, remain the cornerstones of malaria control and eventual elimination efforts.11,30
Acute HIV Infection/Sexually Transmitted Infections
Acute human immunodeficiency virus (HIV) infection refers to the earliest stage of HIV disease, occurring within the first few weeks after exposure. Traveling adolescents may be exposed to HIV through unprotected sexual contact or the sharing of contaminated needles or other drug-related items. Iatrogenic transmission of HIV in hospitals or health centers is, thankfully, now a rare occurrence, but for febrile children who have received significant medical care while traveling, including blood transfusion, acute HIV infection should be considered. During the early stages of infection, the virus rapidly replicates and spreads throughout the body, especially targeting CD4+ T lymphocytes. Because the immunity at this stage is limited, viral loads often are extremely high, making this period one of the most infectious stages of HIV. Acute HIV infection often presents as a nonspecific “mononucleosis-like” illness two to four weeks after exposure. Common symptoms include fever, sore throat, lymph node enlargement, rash, headache, and muscle or joint pain. Some individuals may have diarrhea or neurologic symptoms, while others remain asymptomatic. These signs usually resolve spontaneously within one to two weeks, which can lead to missed or delayed diagnosis. Because antibody tests still may be negative in this early window period, detection relies on antigen/antibody combination assays or PCR to identify viral ribonucleic acid (RNA). Early diagnosis of acute HIV infection is critical, since prompt initiation of antiretroviral therapy reduces viral replication, preserves immune function, and markedly decreases the risk of transmission to others. Pre-travel consultation focusing on the importance of prevention measures, including condoms and pre-exposure prophylaxis (PrEP), particularly for travelers to regions of high HIV seroprevalence, is critical.12,19,30
Uncomplicated infections with gonorrhea, chlamydia, or trichomonas typically do not cause fever. However, both gonorrhea and chlamydia can present with complications that do result in at least low-grade fevers, including gonococcal pharyngitis, pelvic inflammatory disease, orchitis, epididymitis, and gonococcal septic arthritis. A focused sexual history and a high index of suspicion are required, since many adolescent travelers may be reticent to share potentially helpful clinical details, such as sexual interactions or genitourinary complaints.
Rates of syphilis (infection with the treponeme Treponema pallidum) infection have been climbing in many regions, as this organism frequently is overlooked when testing for sexually transmitted infections (STIs) or when treatment is considered. Syphilis is characterized by distinct clinical stages that can progress throughout months to years if untreated. Primary syphilis typically presents as a painless genital, anal, or oral chancre that heals spontaneously while secondary syphilis may cause systemic symptoms, such as fever, malaise, lymphadenopathy, and a characteristic diffuse rash that often involves the palms and soles.12,19
If infection persists, syphilis enters a latent phase, which may last for years without symptoms. In some individuals, it progresses to tertiary syphilis, a destructive stage that can involve the cardiovascular system, skin, bones, and central nervous system, leading to neurosyphilis or gummatous disease. Despite its varied presentations, syphilis remains highly treatable, with intramuscular penicillin G as the treatment of choice at all stages. Testing with rapid plasma reagin is useful in diagnosing syphilis, and titres can be followed to document treatment response or reinfection.12,19
HSV is a common sexually transmitted infection caused by two closely related viruses: HSV-1 and HSV-2. HSV-2 most often is responsible for genital infections, whereas HSV-1 (more commonly associated with oral infections) is increasingly causing genital herpes through oral-genital contact. Transmission occurs through direct skin-to-skin or mucosal contact, even when lesions are not visible, making the infection highly contagious. Genital HSV infection can present with painful blisters or ulcers, itching, dysuria, and sometimes systemic symptoms, such as fever and malaise during the initial outbreak. Fever may be associated with the initial infection but is not often associated with recrudescent disease. After the primary infection, the virus becomes latent in nerve ganglia and can reactivate periodically, causing recurrent symptomatic or asymptomatic viral shedding. Antiviral medications, such as acyclovir, valacyclovir, or famciclovir, can reduce the severity and frequency of outbreaks and lower the risk of transmission, although there is currently no cure for HSV. Condoms as well as pre-travel consultation with adolescents who may engage in sexual activity are critical to prevent HSV infection.12,19,31
Gastrointestinal Infections
Ingestion of undertreated water or contaminated food sources are the principal means of acquiring GI infections while traveling. Most internationally acquired GI infections are self-limited or easily treated. Most bacterial and viral causes of GI infections respond to symptomatic treatment with medications, such as ondansetron and immodium, and, despite problems with resistance globally, may be treated with either fluoroquinolones or azithromycin. Care should be taken in young children if infection with E. coli O157: H7 is suspected or diagnosed — antibiotics may worsen outcomes and lead to hemolytic uremic syndrome.12,19,31
Typhoid fever is a systemic infection caused by the bacterium Salmonella enterica serotype Typhi — and less commonly by Salmonella paratyphi. It is transmitted primarily through ingestion of contaminated food or water, making it a major public health concern in areas with poor sanitation. After ingestion, the bacteria invade the intestinal mucosa, spread to the bloodstream, and disseminate to the liver, spleen, and bone marrow. The incubation period typically ranges from six to 30 days, and the illness can present with prolonged high fever, abdominal pain, headache, malaise, anorexia, and sometimes a characteristic “rose spots” rash on the trunk. Complications of untreated typhoid can include intestinal perforation, hemorrhage, and severe systemic infection, which can be fatal. Diagnosis relies on blood culture in the first week of illness, with stool PCR or stool or bone marrow cultures also used in some cases. Prevention focuses on improved sanitation, safe food and water practices, and vaccination in endemic areas. Treatment consists of appropriate antibiotics, such as ceftriaxone, azithromycin, or fluoroquinolones (depending on local resistance patterns), which reduce the severity and duration of illness and help prevent complications.12,19,32
Non-Malarial Parasites
Most intestinal parasites cause limited intraluminal infections and, thus, do not routinely cause fever or severe systemic disease. Giardia lamblia, one of the most commonly acquired GI parasites, usually is caused by the ingestion of inadequately treated water. It primarily causes localized intestinal infection and only rarely leads to significant extraluminal disease. Its effects are mostly limited to malabsorption, weight loss, and chronic GI symptoms rather than systemic spread. It is treated by a five- to seven-day course of metronidazole or a single dose (50 mg/kg up to 2 g) of tinadazole.14,32
In contrast, Entamoeba histolytica can cause significant extraluminal disease when trophozoites invade the intestinal mucosa and enter the bloodstream. The most common manifestation is a hepatic abscess, which can present with fever, right upper quadrant pain, and hepatomegaly. Less commonly, E. histolytica can disseminate to the lungs, brain, or peritoneum, leading to serious systemic complications. Early diagnosis, usually via stool microscopy or stool antigen or PCR testing, and treatment with antiamoebic therapy, such as metronidazole followed by a luminal agent (paromomycin, iodoquinol) to destroy the cysts remaining in the intestinal tract, are critical to prevent morbidity and mortality from these invasive infections.14,32
Other intestinal parasites, such as the roundworms, whipworms, pinworms, and tapeworms, typically do not cause fever, although cysticercosis, or the systemic spread of Taenia solium (pork tapeworm), has been associated with low-grade fever in some patients.33,34
While not specifically an intestinal parasite, blood flukes, known collectively as bilharzia, can produce a febrile illness in response to acute infection. Bilharzia, or schistosomiasis, is a parasitic infection caused by blood flukes of the genus Schistosoma, transmitted when cercariae in fresh water penetrate human skin, usually during swimming or bathing in contaminated water inhabited by freshwater snails. In the acute phase, which can occur weeks after exposure, some individuals develop Katayama fever, characterized by high fever, chills, headache, malaise, myalgia, and urticaria, often accompanied by eosinophilia. Chronic infection develops as eggs accumulate in tissues, leading to intestinal, hepatic, urinary, or urogenital complications depending on the species. Long-term consequences can include portal hypertension, hepatosplenomegaly, hematuria, bladder fibrosis, increased risk of bladder cancer, and growth or cognitive impairment in children. Diagnosis typically is made by detecting eggs in stool or urine or through serologic testing. Treatment consists of praziquantel, which is effective against adult worms, and supportive care for complications.14
Leishmaniasis is a protozoan parasitic disease caused by species of the genus Leishmania and transmitted to humans through the bite of infected female phlebotomine sandflies. The disease presents in several clinical forms: cutaneous leishmaniasis (localized skin ulcers), mucocutaneous leishmaniasis (destructive lesions of the nose, mouth, and throat), and visceral leishmaniasis (kala-azar), which is characterized by prolonged fever, hepatosplenomegaly, weight loss, and pancytopenia. Risk is greatest in regions of South Asia, East Africa, South America, and the Mediterranean. Transmission can occur in both rural and urban settings, often associated with poverty, malnutrition, and displacement.14
The diagnosis of leishmaniasis relies on demonstration of the parasite and clinical suspicion based on exposure history. Microscopy can reveal amastigotes in tissue aspirates (skin lesions, bone marrow, or splenic aspirates), while culture and molecular tests, such as PCR, provide greater sensitivity. Serologic assays can aid in visceral leishmaniasis diagnosis. Treatment depends on the form and geography of infection. Options include liposomal amphotericin B (first-line in many regions for visceral disease), pentavalent antimonial agents (still widely used in cutaneous and visceral leishmaniasis in resource-limited areas), miltefosine (oral therapy for certain forms), and paromomycin. Supportive care and management of complications (e.g., secondary infections, anemia) also are critical.14
Leptospirosis
Leptospirosis is a bacterial infection caused by spirochetes of the genus Leptospira, typically transmitted to humans through contact with fresh water, soil, or food contaminated with the urine of infected animals, most commonly rodents. The disease can range from a mild, flu-like illness with fever, headache, myalgias, and conjunctivitis to a severe, life-threatening form known as Weil’s disease, which involves renal failure, hyperbilirubinemia, coagulopathy, and hypotension. Leptospirosis is more common in tropical and subtropical regions and often occurs after flooding or exposure to contaminated water. The diagnosis is based on serologic testing, PCR, or culture in specialized laboratories.13,14
Treatment includes prompt administration of antibiotics, such as doxycycline for mild cases and intravenous penicillin or ceftriaxone for severe disease, along with supportive care for organ dysfunction. Preventive measures focus on avoiding contact with potentially contaminated water, rodent control, and protective clothing in high-risk occupations or activities.13,14
Tick-Borne Illness
Ticks can transmit a wide variety of bacterial, viral, and parasitic diseases. (See Table 4.) Examples of global epidemiologic importance include Lyme borreliosis in Europe, North America, and parts of Asia; tick-borne encephalitis (TBE) across Europe and northern Asia; Crimean-Congo hemorrhagic fever (CCHF) in Africa, Eastern Europe, and Central Asia; babesiosis in multiple continents, including North America; and rickettsial infections, such as Rocky Mountain spotted fever and Mediterranean spotted fever, which occur regionally in all the world’s continents except Antarctica. Many tick-borne illnesses present with nonspecific symptoms, such as fever, chills, headache, fatigue, and muscle aches. Therefore, a detailed travel history, including insect or tick bites, is critical in addition to seeking expert consultation regarding regional tick species and disease distribution. Diagnosis varies depending on illness and region. For instance, erythema migrans may suggest Lyme borreliosis in endemic areas, while hemorrhagic symptoms could indicate CCHF. Laboratory confirmation may involve serology, PCR, or blood smear examination (for parasitic infections, such as babesiosis).
Table 4. Tick-Borne Infections14,17,24,32 |
Lyme Disease
Anaplasmosis
Babesiosis
Rocky Mountain Spotted Fever
Tick-Borne Relapsing Fever
Tick-Borne Encephalitis
Crimean-Congo Hemorrhagic Fever
Tularemia
African Tick Bite Fever
|
Preventing tick-borne illnesses relies on a combination of personal protection, environmental measures, and — where available — vaccination. Personal measures include wearing protective clothing, using tick repellents containing N,N-diethyl-meta-toluamide (DEET) or permethrin, performing regular tick checks after outdoor activities, and promptly removing attached ticks to reduce transmission risk. Public health strategies, such as controlling tick populations through habitat management, livestock treatment, and awareness campaigns, also are important in endemic regions. Vaccination plays a role in certain areas: Effective vaccines against tick-borne TBE are available and widely used in parts of Europe and Asia, significantly reducing incidence. Single-dose doxycycline prophylaxis is recommended after tick bites in some cases (in regions with heavy Lyme disease burden, treatment within 36 hours of the tick bite) and may be indicated or considered in all children returning from travel.12-14
Many bacterial tick-borne infections, including rickettsioses and Lyme disease, respond to antibiotics, such as doxycycline. Babesiosis requires antiparasitic combination treatment, such as atovaquone with azithromycin or clindamycin with quinine, indicated for severe disease. Viral infections, such as TBE and CCHF, lack specific antiviral treatments, so management mainly is supportive.12-14
Dengue/Chikungunya Viruses
Dengue and chikungunya viruses are mosquito-borne infections primarily transmitted by Aedes aegypti and Aedes albopictus, which thrive in tropical and subtropical regions worldwide. Both illnesses often present with fever, headache, rash, and muscle and joint pain, making them clinically difficult to distinguish early on from each other and from other viral infections, such as influenza. Dengue can range from a mild flu-like illness to severe disease with thrombocytopenia and resultant hemorrhage, multisystem organ impairment, and capillary leak, sometimes called severe dengue or dengue hemorrhagic fever (DHF). Repetitive infection with dengue may cause “breakbone fever” with severe myalgias and arthralgias. Chikungunya, while rarely fatal, is notable for causing intense and sometimes long-lasting joint pain that can persist for weeks to months after the acute infection.11,12
Neither dengue nor chikungunya has a specific treatment. Care mainly is supportive — with hydration, fever control with acetaminophen, and support of organ systems important for DHF. Aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) should be avoided when dengue is suspected because of the risk of worsening bleeding platelet function. A dengue vaccine exists and is used in certain high-risk populations, but no widely available vaccine yet exists for chikungunya (although candidates are in development). Chikungunya treatment is supportive as well, with hydration and NSAIDs indicated for severe myalgias. Mosquito avoidance strategies are critical to the prevention of both illnesses, with appropriate clothing, insect repellant, and bed nets being cornerstones of prevention.11,12,14
Mpox
Mpox (monkeypox) is a zoonotic viral infection that is contracted after close physical contact with either an infected person or an infected animal (generally rodents or primates). Congenital mpox has been described. Clinical features often begin with prodromal symptoms, such as fever, chills, lymphadenopathy, headache, myalgia, and fatigue. Within a few days, a characteristic rash develops, typically progressing from macules to papules, vesicles, pustules, and scabs. Lesions often are well-circumscribed, deep-seated, and can be painful. Unlike varicella, lymphadenopathy is a distinguishing feature. The rash can be localized or disseminated, commonly involving the face, extremities, and mucous membranes, including genital and perianal sites in recent outbreaks.
The diagnosis of mpox is confirmed by PCR testing of skin lesion scrapes or swabs. Children with mpox primarily are managed with supportive care, but antiviral agents are recommended for patients at higher risk, including infants, children younger than 8 years of age, immunocompromised patients, and those with severe or complicated disease. Tecovirimat (TPOXX) is the first-line option, given orally or intravenously for 14 days at the following doses based on patient weight:11,12,14
- < 3 kg: 33.3 mg every 12 hours;
- < 6 kg: 50 mg every 12 hours;
- 6-13 kg: 100 mg every 12 hours;
- 13-25 kg: 200 mg every 12 hours;
- 25-40 kg: 400 mg every 12 hours; and
- > 40 kg: 600 mg every 12 hours.
Alternatives include brincidofovir (weekly dosing: < 10 kg: 6 mg/kg, 10-48 kg: 4 mg/kg, > 48 kg: 200 mg) or cidofovir (5 mg/kg intravenously twice per week), although these are less commonly used. Vaccinia immune globulin may be considered for severe disease or when vaccination is not possible. A vaccine for mpox (Imvanex) is available and is given as a two-dose series separated by 28 days.11,12,14
Supportive care remains the mainstay of treatment and is adequate in the majority of cases. Maintenance of hydration, pain control, and management of secondary bacterial infections are important. In severe cases or high-risk patients, including children, immunocompromised patients, neonates or infants, or pregnant individuals, antivirals, such as tecovirimat, may be considered, along with brincidofovir or cidofovir in select circumstances. Vaccination with modified vaccinia Ankara (MVA-BN, also known as Jynneos) is used for both PrEP and post-exposure prophylaxis in high-risk contacts.
Meningitis/Encephalitis
Meningitis and encephalitis are potentially life-threatening infections that occur with higher rates in some areas of the world. The “meningitis belt” is a region of sub-Saharan Africa that stretches from Senegal in the west to Ethiopia in the east. It includes about 26 countries across this band. This area is prone to large seasonal epidemics of meningococcal meningitis, especially during the dry season (December to June) when dust, low humidity, and close human contact increase transmission. Given the rapid progression of disease that may be seen, especially with bacterial meningitis, a high index of suspicion with early consideration of lumbar puncture and broad-spectrum antibiotic coverage (ceftriaxone 100 mg/kg/day intravenously, given once daily [maximum 4 g/day] or 50 mg/kg intravenously every 12 hours [maximum 2 g per dose] and vancomycin 60 mg/kg/day intravenously, divided every six to eight hours [maximum 2 g per dose or ~4 g/day total]).11,12,14
Viral encephalitis, including HSV encephalitis, Venezuelan equine encephalitis, Japanese encephalitis, and West Nile virus infection, typically causes fever, seizures, confusion, and focal neurological deficits. With the exception of HSV, most viruses that cause encephalitis are transmitted via the bite of infected mosquitoes. The diagnosis of both meningitis and encephalitis rests on high clinical suspicion as well as CSF interpretation. CSF microbacterial culture and PCR testing are critical for obtaining organism-specific diagnoses.11,12,14 Viral encephalitis treatment is mostly supportive, except for HSV, where intravenous acyclovir (children and infants older than 3 months of age should receive 10 mg/kg intravenously every eight hours based on actual body weight and neonates younger than or equal to 3 months of age should receive
20 mg/kg IV every eight hours) may be lifesaving. Other viral encephalidites, like Japanese encephalitis or West Nile virus, have no specific antiviral treatment, so management focuses on supportive care and complication prevention. Vaccines exist for several pathogens (e.g., meningococcal, pneumococcal, Hib, and Japanese encephalitis vaccines), making immunization and public health measures crucial preventive strategies.11,12,14
Hemorrhagic Fevers: Ebola and Marburg Viruses
Viral hemorrhagic fevers (VHFs) are a group of illnesses caused by RNA viruses from several families, including Arenaviridae (Lassa fever), Filoviridae (Ebola, Marburg), Bunyaviridae (CCHF, Rift Valley fever, the hantaviruses), and Flaviviridae (yellow fever, dengue). They occur worldwide but are most common in Africa, Asia, and South America.
Transmission varies by virus: Some are spread by arthropod vectors (mosquitoes, ticks), others by contact with infected animals, and many by direct contact with infected human body fluids. The incubation period for these extremely contagious and virulent viruses can be up to three weeks, making their consideration in children returning from travel from high-risk regions of critical importance. VHFs typically begin with nonspecific symptoms, such as fever, fatigue, muscle pain, and headache, followed by varying degrees of hemorrhage, shock, and multiorgan failure.
Severity and outcome differ by virus, with Ebola and Marburg viruses often causing severe disease with high mortality, while Lassa fever can produce mild to life-threatening illness. Yellow fever may cause jaundice and bleeding with a high fatality rate in severe cases. Because the initial symptoms mimic other tropical infections, clinical suspicion, epidemiological context, and laboratory confirmation are crucial for diagnosis. Treatment largely is supportive, focusing on careful fluid management, hemodynamic stabilization, and treatment of complications such as bleeding or organ failure. Antiviral options are limited: ribavirin is effective against some arenaviruses (e.g., Lassa fever) and certain bunyaviruses (e.g., CCHF), but not filoviruses or flaviviruses. For Ebola virus disease, specific monoclonal antibody therapies (such as atoltivimab/maftivimab/odesivimab and ansuvimab) have shown clear survival benefits. Additionally, remdesivir is seeing use in both Ebola and Marburg virus outbreaks, although the effect is not yet clear. Vaccines exist for yellow fever and Ebola (rVSV-ZEBOV), and an experimental vaccine has been developed for Marburg (MK01) that is under study.35
Resources
A variety of resources exist for both travelers seeking pre-travel consultation or clinicians seeking information when treating a febrile child who has returned from travel. Consultation with infectious disease specialists, if available, may be helpful. Also, local and state public health officials may be helpful or required when certain infectious agents are considered. The following is a sampling of the major online sites of value to travelers and clinicians.
Government and International Public Health Agencies
- CDC Travelers’ Health: offers destination-specific health advice, vaccine recommendations, disease prevention tips (like malaria prophylaxis), and Travel Health Notices
- World Health Organization Travel Advice: provides updates on infectious disease risks, vaccination requirements, and regional travel health guidance
CDC’s Yellow Book (Health Information for International Travel)
- A comprehensive guide, updated regularly, offering country-specific disease risks, vaccine guidance, and preventive measures for travelers and health professionals
- Also includes resources for budget-conscious travelers and broader pre-travel consultation advice
Specialized Travel Medicine Networks and Surveillance Tools
- International Society of Travel Medicine (ISTM): maintains a Global Clinic Directory, helpful for locating pre- and post-travel clinics globally
- GeoSentinel: ISTM- and CDC-backed surveillance network for travel-related disease trends
- ProMED, HealthMap, Epidemic Tracker, EpiCore: real-time outbreak monitoring platforms that aggregate global disease activity and alerts
Traveler-Friendly Support and Clinic Resources
- International Association for Medical Assistance to Travellers: hosts a directory of travel medicine professionals across 80+ countries
- Immunize.org: offers a travel vaccines directory with guidance from CDC, WHO, and supportive immunization resources
- Travel Clinics and Services: examples include Passport Health (U.S.-based clinics with travel vaccines and advice) and university-led clinics, such as Stanford Health or University Health Services-Berkeley, offering pre-travel consultations
Textbooks
- Principles and Practice of Infectious Diseases (Mandell, Douglas, and Bennett)
- The gold-standard reference in infectious disease medicine
- Contains sections on travel-related infections and approaches to post-travel fever evaluation
- Travel Medicine (edited by Keystone, Kozarsky, Connor, et al)
- A core specialty text devoted to travel health
- Includes dedicated chapters on post-travel illness, with fever highlighted as the most common and clinically important presentation
- Hunter’s Tropical Medicine and Emerging Infectious Diseases (Ryan, Hill, Solomon, et al)
- A classic text in tropical and global infectious diseases
- Comprehensive coverage of tropical causes of fever (malaria, arboviruses, typhoid, rickettsioses) in travelers returning from endemic regions
- Oxford Handbook of Tropical Medicine (Davidson, Seale, Brent, et al)
- Portable clinical handbook with practical guidance
- Contains concise sections on approach to fever in travelers and rapid assessment protocols
Conclusion
In conclusion, travel is becoming increasingly common for children and families and, while these excursions frequently are low-risk, an awareness of the breadth of infections that exist in other regions is necessary for the emergency clinician. Travel medicine plays a vital role in helping individuals prepare for the health challenges they may face abroad. From mosquito-borne illnesses (dengue and malaria) to food- and water-related infections to region-specific threats (VHFs or meningitis), the risks are diverse and often unpredictable. In children returning from travel, fever always should be approached with caution, since it may signal a wide range of infections from common viral illnesses to serious diseases, such as malaria, typhoid, or dengue. Careful attention to travel history, exposure risks, and early medical evaluation is essential to guide prompt diagnosis and treatment. By maintaining a high index of suspicion and considering region-specific infections, clinicians can ensure timely management and improve outcomes for these young travelers.
Joseph U. Becker, MD, is Clinical Associate Professor, Department of Emergency Medicine, Stanford University, Palo Alto, CA.
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Every year, a significant number of families travel internationally with children, who then have a high rate of febrile illness after returning home. While most travel-acquired infections are self-limited and mild, some diseases may rapidly become fatal, and early recognition and aggressive management can maximize the child’s outcome. This review presents a focused clinical approach to caring for a child returning from international travel with a fever.
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