EPIDEMIOLOGY AND CLINICAL MANIFESTATIONS OF IMPORTED SCHISTOSOMIASIS

Background: Several outbreaks of schistosomiasis among travellers, exp atriates and military serviceman have been reported in recent years. P atients and Methods: Travel and medical histories as well as clinical features of 62 German and 21 native patients with schistosomiasis who were presented to a German outpatient clinic for infectious and tropic al diseases were investigated in order to identify the risk factors le ading to infection in travellers and expatriates. Results: All patient s were able to remember the incidents which led to a likely exposure t o cercariae of schistosoma spp. Fifty-nine German patients (95%) acqui red infection in Africa, 2 (3%) in South America and one each (2% each ) in the Euphrat and the Mekong River, respectively. All but 1 native patients acquired infection in Africa. The highest proportion of infec tion (45% in Germans and 37% in native patients) was imported from Wes t Africa. Patients returning from this area had had either contact wit h tributaries of the Niger or with waters of the Volta River, notably the Lake Volta and/or its delta. The most sensitive method for detecti on of schistosomiasis appeared to be a combination of thorough travel history and serological testing (IHA, IFAT and ELISA) of all patients with possible infection. Conclusions: In the investigated group, most infections were acquired by travellers on a lengthy and adventurous jo urney or by expatriates venturing outside their normal areas of activi ty. Mosi patients knew that they travelled in an area endemic for schi stosomiasis but were uninformed about the risks they took with their b ehaviour in a specific setting. Others simply could not avoid skin exp osure to freshwater like backpacking tourists travelling in boats on t he Niger or Congo River and native patients. Travellers to the tropics should therefore be informed thoroughly about the dangers of water-re lated diseases such as schistosomiasis.