High Prevalence and Presumptive Treatment of Schistosomiasis and Strongyloidiasis among African Refugees

Abstract

Schistosomiasis and strongyloidiasis cause substantial morbidity and mortality among hundreds of millions of infected persons worldwide. In the United States, these infections are most commonly found among international travelers, immigrants, and refugees from areas of endemicity. Refugees resettled to the United States since 2000 include >3800 "Lost Boys and Girls" of Sudan and 8000 Somali Bantu. Many Lost Boys and Girls of Sudan reported chronic abdominal pain only since arrival, and some received diagnoses of schistosomiasis or strongyloidiasis. We assessed seroprevalence of these infections among these refugees and hypothesized an association between infection and abdominal pain. We offered a survey assessing chronic abdominal pain and serologic testing for schistosomiasis and strongyloidiasis to all 800 attendees of a Lost Boys and Girls of Sudan reunion in the United States. Serologic testing was performed on preimmigration specimens obtained from 100 United States-bound Somali Bantu refugees. Of the 462 Sudanese refugees (58%) tested, 44% and 46% were seropositive for schistosomiasis (primarily due to Schistosoma mansoni) and strongyloidiasis, respectively; 24% of those who tested positive for schistosomiasis had S. mansoni antigenemia. Forty-six percent reported chronic abdominal pain, which was not associated with either infection. Among 100 Somali Bantu, 73% and 23% tested seropositive for schistosomiasis (primarily due to Schistosoma haematobium) and strongyloidiasis, respectively. The high seroprevalence of schistosomiasis and strongyloidiasis among Sudanese Lost Boys and Girls and Somali Bantu refugees supports presumptive treatment for these refugees. Current refugee resettlement policies inadequately address these diseases; our data support consideration of predeparture presumptive therapy for all refugees from areas of endemicity.