By Stan Deresinski, MD, FACP, FIDSA
Clinical Professor of Medicine, Stanford University
SYNOPSIS: An outbreak of Marburg virus disease, an illness resembling Ebola, is occurring in Ghana, only the second such event in West Africa. Will it spread beyond Africa?
SOURCE: ProMED International Society for Infectious Diseases. Marburg virus disease — Ghana. July 27, 2022. https://promedmail.org/promed-posts/
The first cases of Marburg virus disease recognized in Ghana resulted in the deaths of a 26-year-old man on June 27, 2022, and of a 51-year-old man on June 28, 2022. The two, both farmers, were unrelated. The World Health Organization (WHO) confirmed two additional cases in Ghana a few weeks later. The four cases occurred in three different regions of Ghana.
A total of 108 contacts, including healthcare workers and family members, of the first two cases self-quarantined with daily monitoring for 21 days and none were found to have developed Marburg virus disease. The WHO alerted neighboring high-risk countries where previous outbreaks have occurred, including Angola, the Democratic Republic of Congo, Kenya, South Africa, and Uganda. The WHO assessed the risk of the current situation to be high at the national level, moderate at the regional level, and low at the global level.
COMMENTARY
Marburg virus was first identified in the context of two outbreaks in Europe in 1967, one in Belgrade, Serbia, and one in Germany in both Frankfurt and Marburg. These outbreaks were traced to laboratory work with African green monkeys imported from Uganda. The occurrence of human cases in 2008 in travelers visiting bat-infested caves in Uganda provided an important clue to the epidemiology of the infection. Since then, cases also have been reported from Angola, Democratic Republic of the Congo, Kenya, South Africa, and Zimbabwe. The first and only occurrence in West Africa prior to the Ghana cases occurred in 2021 in Guinea. The virus also has been found in fruit bats in Sierra Leone.
Marburg virus, like Ebola virus, is a filovirus, and the manifestations and severity of the infections are similar. In both cases, their natural host is fruit bats, which may transmit to humans with subsequent spread between humans. Human-to-human transmission occurs by direct contact with blood, tissue, and body fluids of infected individuals, as well as contact with contaminated fomites, such as bedding and clothing. As with Ebola, transmission may occur as a result of direct contact during burial rituals.
The WHO indicates that the reported mortality rate of Marburg virus disease is approximately 50%, but, in the largest outbreak, which occurred in Angola in 2005, 329/374 (88%) of people infected died. There are no therapeutics or vaccines proven to be effective against Marburg virus infection.
Should we worry about Marburg virus disease, an African disease, in the United States? I have always thought not, but experience suggests otherwise. The 2014 importation of Ebola into the United States is one example — and now we have monkeypox.
REFERENCE
- World Health Organization. Marburg virus disease. https://www.who.int/health-topics/marburg-virus-disease#tab=tab_1
