A preliminary analysis of sentinel surveillance data of the European Network on Imported Infectious Disease Surveillance (TropNetEurop) shows 88 cases of imported schistosomiasis for 2007 (17 cases of Schistosoma haematobium
, 44 of S. mansoni
, 3 of S. japonicum
, and 27 unknown species, e.g. early stage, Katayama fever) . Although clinical reporting data for schistosomiasis are notoriously difficult to assess due to the chronic nature of the disease and thus very long periods before diagnosis is confirmed, the analysis gives a good idea about how this infection is brought into Europe.
Reported patients with schistosomiasis are predominantly male (71.6% male, 28.4% female). Median age has declined in comparison to recent years and is now at 25 years, (32 years in 2005). The proportion of immigrants in the total patient population remains at 53% (43.6% in 2005). Main purposes of travel reported by infected Europeans were tourism (47%) and missionary/humanitarian work (29%).
Unlike in 2006, but very much like in previous years, West Africa contributed the most cases. Infections from countries outside Africa do occur, but are very rare. In 2007, most infections were reported to have been imported from Mali, Senegal, Ghana, Democratic Republic of the Congo, and Uganda.
A high percentage of patients (59%) were asymptomatic when infection established. Diagnosis has to be sought actively in those patients who have been exposed. In those with clinical complaints, symptoms were quite unspecific. Most patients complained about fever, respiratory and genitourinary symptoms. Once diagnosed, the clinical management was straightforward: the majority of patients were treated on outpatient basis. Only 8% were admitted as inpatients and kept for a median time of four days. All patients were cured with praziquantel.
In consideration that a simple and effective therapy is available, schistosomiasis should be considered for diagnostic differential diagnosis when dealing with patients who might have been exposed in areas where this disease is endemic.