West African Travel-Related Illnesses: Not Just Ebola
Amesh A. Adalja, MD, FACP, FACEP, June 12, 2015
Since the height of the West African Ebola outbreak, enhanced entry screening has been conducted of travelers who originate in Sierra Leone, Guinea, and Liberia upon their arrival in the US. While it is widely known that no cases of Ebola have been detected in this manner, many other infectious diseases have been diagnosed. Thus, a potential secondary benefit of this enhanced scrutiny is that it offers the opportunity to develop a differential diagnosis for such travelers, allowing one to capture and intervene in other illnesses. A paper from the GeoSentinel Surveillance Network (which spans 6 continents and includes 57 travel clinics), published in the Annals of Internal Medicine, provides useful information for such an effort.
Six Years of Data
Boggild et al. used GeoSentinel data from September 2009 through August 2014 pertaining to travelers and new immigrants from the 3 West African nations affected by Ebola. Querying the database resulted in 805 individuals who had attended a GeoSentinel clinic and received a confirmed or probable diagnosis.
Systemic febrile illness was the most common syndrome, followed by acute diarrhea. The most frequent diagnoses in travelers were:
- 1. Malaria (primarily Plasmodium falciparum)
- 2. Acute diarrhea
- 3. Nonspecific viral syndrome
- 4. Upper respiratory tract infection
By contrast, the most frequent diagnoses in recent immigrants were:
- 1. Latent tuberculosis
- 2. Dental caries
- 3. Schistosomiasis
- 4. Strongyloidiasis
- 5. Giardiasis
Of note, 5 cases of acute HIV infection were diagnosed as well.
Travel History Crucial
This study highlights 2 important clinical maxims: Travel history is crucial, and common things (such as malaria) are common.
As should be apparent from the events over the past year, travel history is a crucial aspect of patient care. Moreover, while MERS, Ebola, chikungunya, and Lassa fever have appeared—and will continue to appear—in the US via infected international travelers, domestic travel history should not be overlooked, as diseases such as Rocky Mountain spotted fever, histoplasmosis, plague, and coccioidiomycosis have specific geographic niches in the US.
Boggild AK, Esposito DH, Kozarsky PE, et al. Differential diagnosis of illness in travelers arriving from Sierra Leone, Liberia, or Guinea: a cross-sectional study from the GeoSentinel Surveillance Network. Ann Intern Med 2015;162:757-764.