By Carol A. Kemper, MD, FACP
Noble LM, et al. The Impact of Injection Anxiety on Education of Travelers About Common Travel Risks. J Travel Med 2013 Nov 19, 2013. doi:10.1111/jtm.12081. [Epub ahead of print]
I recall attending the International Society of Travel Medicine conference in Acapulco years ago, when a clever colleague conducted a clinical survey of conference participants regarding their usual advice to travelers to Mexico — and how many of them followed their own advice (very few). Conducting my own personal experiment, I can testify to the fact that eating street food in Mexico does, indeed, result in gastrointestinal illness. Infectious Disease physicians apparently like to take risks when it comes to their own travel advice.
Turns out — our clients are not much better at following our travel medicine recommendations, perhaps for different reasons. These authors examined the extent to which anxiety or fear about immunizations affected the retention of travel medicine consultation. Standardized information was provided to 105 pre-travelers. Clinicians were also asked to gauge the level of anxiety of the pre-traveler.
Each pre-travel client completed a self-reported survey regarding their general anxiety about injections and needle phobia — and then these results were compared with the ability to recall specific information immediately post-consultation and >24 hours later. Unfortunately, immediate recall of 15 different pieces of information varied from only 2% to 70% — and decreased even further by the following day. The inability to retain information appeared unrelated to injection anxiety or fear of needles. More than one-third (39%) expressed varying levels of anxiety of immunization, and clinicians were pretty good at gauging the anxiety level of their clients. (I would think anxiety about the cost of immunization might be more important than fear of needles).
Moonan PK, et al. Transmission of multidrug-resistant tuberculosis in the USA: A cross-sectional study. Lancet Infectious Dis 2013;13:777-784.
In order to assess the risk of transmission of resistant tuberculosis within the U.S. — and contributing factors — Moonan et al analyzed genotypic clustering of MDR-TB isolates. The authors gathered all cases of MDR-TB reported to the US National Tuberculosis Surveillance System (NTSS) and National Tuberculosis Genotyping Service (NTGS) from eight states, including California from 2007 to 2009, Texas from 2007 to 2009, as well as Colorado, Maryland, New York , Massachusetts, Tennessee and Washington. Drug resistance was defined as any resistance reported to the NTSS; and for the purposes of this project, genotypes were defined as a discrete combination of spoligotype and 12-locus variable-number-tandem repeat units. A cluster was defined as at least two cases of MDR TB, including at least one study case and another case in one of the 8 states with a matching genotype between 2005 and 2011. The index case was temporally the first case identified in a cluster. And epidemiological links were the same as those usually used for contact investigation activities, such as family member, close colleague, and other individuals in close, regular contact.
From the database, 268 cases of MDR-TB were identified during the study period. Of these 168 cases were reported from one of the eight states above, 92 (55%) of whom were willing to participate in an interview. A total of 75 (82%) of these 92 people were foreign-born. Based on the in-depth interviews and available health records, the investigators determined that (9%) of these 92 people developed TB as the result of an exposure within the United States to a recognized source, and 12 people (13%) were part of an outbreak resulting from transmission within the U.S. but from an unknown source. Four of these later served as the source for another case.
Therefore 22% of the MDR-TB cases were the result of exposure to a recognized or unknown case of TB within the U.S. Twenty (22%) of the MDR cases were diagnosed within 3 months of entry into the U.S., and therefore probably had active TB on entry to the U.S. And 38 (41%) were diagnosed with reactivation TB that proved to be MDR. A smaller percent of the MDR-TB cases (15%) were considered relapsed TB cases, from a prior recognized episode of TB. There was insufficient information to classify (10%) of the cases based on their presentation. Notably, 3 individuals diagnosed with XDR-TB (from Nepal, Russia and Krygyzstan) were all diagnosed within 3 months of entry into the U.S.
Of these 92 cases, 28% had the same genotype as another individual with MDR-TB in the same state during the surveillance period. Clustered cases were also more likely to be male, Latino, in prison at the time of diagnosis, and have an isolate of Euro-American phylogenetic lineage. Fourteen clusters were identified in total, 13% of which were of Euro-American phylogenetic lineage. Eights clusters had an identifiable source case; two included transmission to a child, and one across state lines. More than half the cases involved excessive use of alcohol or illicit drugs. Overall, people with MDR-TB attributed to transmission within the U.S. were more likely to be male, have been born in the U.S., be of Hispanic ethnic origin, abuse illicit drugs or alcohol, and have an isolate of Euro-American phylogeny.
During this investigation, the authors identified 1166 people exposed to cases of MDR-TB, 353 of whom (30%) had evidence of latent TB. Assuming a 10% risk of active disease, exposure to these cases might result in approximately 35 future cases of MDR-TB within the U.S.. Data is lacking as to how best to prophylax these exposures.
Unfortunately, most of these cases of newly diagnosed and reactivation TB were not captured on entry to the U.S. Confronting yet again another case of active pulmonary TB in my Silicon Valley-based immigrant population, I am repeatedly asked why individuals with TB are not screened by the public health department. Efforts in immigration clinics are directed at capturing cases of active TB — not latent TB, and the public health department does not have the resources to screen and prophylax cases of latent TB — that is our job. Even persons with active TB can slip by these screening efforts — as illegal immigrants — or by simply arriving on one of the new work VISAs, visiting family for an extended time, or arriving as a refugee or under asylum (where no TB screening is required — only a vague recommendation they see a doctor after arrival in the U.S.).
Durovni B, et al. Effect of improved tuberculosis screening and isoniazid prevention therapy on incidence of tuberculosis and death in patients with HIV in clinics in Rio de Janeiro, Brazil: A stepped wedge, cluster-randomised trial. Lancet 2013; Published on-line August 13, 2013. S1473-3099(13)70187-7.
The authors conducted a large-scale intervention in 29 HIV clinics in Rio de Janeiro to assess whether improved TB screening and INH treatment would result in a lower incidence of TB infection and death in their HIV-infected population. TB remains a significant problem in Brazil, and 10% of the cases of TB in Rio are HIV-co-infected. TB continues to be a significant contributor of death in people with HIV-infection in Brazil.
The intervention was simply to increase screening of individuals attending HIV clinics for TB, to improve the use of PPD and detection of positive skin tests, and to increase the use of INH prevention. Two clinics were randomly selected to begin the intervention in a step-wise fashion every two months from 2005-2009. In addition, a control period for examining rates of TB and death was selected from 2003-2005.
During the intervention period, rates of skin testing increased from 19 person/100 person-years to 59/100 person-years. Isoniazid prevention increased from 36/100 eligible person-years to 144/100 eligible person-years. A total of 221 cases of TB were diagnosed during the control period and 254 cases during the intervention period. A total of 17,413 persons visited the clinic at least once during the study period; 12,816 of these were eligible for the intervention — so this was an enormous interventional study. Of these 472 had a positive TB skin test at study start. Of the remainder, 60% had at least one skin test during the study period, and of those eligible for a second test, 47% received a second test. Twenty percent had a positive result, and 82% started INH treatment. Of these, 85% of those starting INH completed a course of therapy. 1.5 % reported treatment-limiting side effects.
After adjusting for age, CD4 count, and sex, the intervention — although only 4 years in duration — was associated with a 27% reduction in TB cases and a 31% reduction in TB deaths. A secondary analysis examining the effect of TB screening on retention in clinics, and the benefit specifically to those patients retained in care found an even greater benefit to the intervention with a 58% reduction in the incidence of TB infection and a 55% reduction in TB and death. The authors believe the intervention proved to, as a whole, result in improved care by increasing awareness of TB in the study population, and improved diagnosis of active TB cases.
