Eosinophilia and Select Parasitic Infections Among People Seeking Humanitarian Protections in the United States After Travel Through the Darién Jungle: A Multicenter Cross-sectional Study

Background. People seeking humanitarian protections in the United States often have complex ecologic exposures during their migration, as in the Darién Jungle, a rainforest between Colombia and Panama. We characterized eosinophilia and select parasitic infections in this population. Methods. We conducted a cross-sectional study of clinical evaluations of unhoused people seeking humanitarian protection in Boston and New York City. Patients underwent laboratory testing based on clinician discretion. We extracted data regarding migration history and testing for eosinophilia (>500 cells/μL), Strongyloides infection, and Chagas disease. We used χ² testing to evaluate the association between exposure to the Darién Jungle and test results. Results. Our sample included 632 people (median age, 27 years; 55.0% female), primarily from Venezuela (32.0%), Ecuador (16.6%), Colombia (14.7%), and Haiti (13.3%). Of these, 411 people (65.0%) crossed the Darién Jungle. The median (IQR) duration in the Darién Jungle was 5 (4–7) days. We found that 71 people (11.2%) had eosinophilia. Of 438 people who completed testing for Strongyloides infection, 21 (4.8%) were positive, which occurred more frequently in people with eosinophilia (P = .006). Testing for Chagas was negative in all people. Children were more likely to have eosinophilia as compared with adults (odds ratio, 1.76; 95% CI, 1.04–2.95). There was no statistically significant association between crossing the Darién Jungle and eosinophilia (odds ratio, 1.13; 95% CI, .67–1.95). Conclusions. Eosinophilia and Strongyloides infection are common among unhoused persons seeking humanitarian protections in the United States, particularly children. Clinicians should screen for these conditions and be vigilant for migration-related exposures.