Acute Febrile Respiratory Reaction After Praziquantel Treatment During Asymptomatic Late Form of Acute Schistosomiasis


Corresponding Author: Andreas L.C. Neumayr, MD, DTM&H, MCTM, Swiss Tropical and Public Health Institute, Socinstr. 57, P.O. Box, Basel CH-4002, Switzerland. E-mail:


Paradoxical reactions (Jarish Herxheimer-like reactions) have been described in patients treated with praziquantel (PZQ) during acute schistosomiasis (infected ≤ 3 mo), while PZQ treatment of chronic schistosomiasis is generally considered to be safe. We report an acute febrile reaction with respiratory decompensation following PZQ treatment in a 17-year-old male patient who had no potential (re)exposure to infection for at least 5 months and was therefore considered to have reached the chronic stage of disease. We speculate that the clinical manifestations in our patient constitute a very late paradoxical reaction in an unusually long acute phase of infection.