“We need to remind physicians and other health care providers to take a travel history,” Dr. Hamer concluded. “If you do not know that a patient has been in West Africa, then malaria and EVD might be missed altogether.”

Dr. Justin Stoler, from the University of Miami’s Department of Geography and Regional Studies, Coral Gables, Florida, told Reuters Health by email, “Given increased air travel and accelerating globalization, clinicians, now more than ever, need to keep their epidemiological knowledge current. A physician might reasonably suspect malaria in any febrile patient who traveled to any rural area in sub-Saharan Africa without the use of malaria prophylaxis. Given the various incubation periods and non-specific symptoms of most tropical febrile illnesses, and higher probability of severe disease, this report underscores the need for innovation and widespread use of point-of-care diagnostics for tropical medicine.”

“Communicable diseases are geographically diverse and very poorly understood in sub-Saharan Africa,” Dr. Stoler said. “This report offers a glimpse of the complexity of tropical medicine in West Africa (and more broadly, sub-Saharan Africa). Recent seroprevalence studies from other sub-Saharan African nations yield different mixes of infections, as local immunology and exposures vary greatly from those of non-immigrant travelers. EVD is yet another reminder of how little we know about infectious disease epidemiology in Africa.”

This research was supported primarily by the U.S. Centers for Disease Control and Prevention, which supports GeoSentinel Surveillance Network, along with the International Society of Travel Medicine. Dr. Hamer reported being principal investigator for GeoSentinel and owning equity in Alere, a company that produces a rapid malaria diagnosis test; coauthor Dr. Castelli reported receiving research support from GeoSentinel and being an investigator in a clinical trial of a malaria drug for Sigma Tau.