An outbreak of acute schistosomiasis following a church retreat to Mwanza, Tanzania, 2008.

Clinical and laboratory findings are described from 77 persons from Nairobi, Kenya, of whom 66 were diagnosed with acute Schistosoma mansoni infection following a trip to Mwanza, Tanzania. Unusual ocular symptoms were observed as a rare manifestation of acute schistosomiasis. The outbreak highlights the risk of swimming in Lake Victoria.