title: Schistosomiasis in Swedish travellers to sub-Saharan Africa: Can we rely on serology?
abstract: In the absence of egg excretion, laboratory diagnosis of recently acquired schistosomiasis is dependent on serology. 42 of 83 Swedish adventure tourists to sub-Saharan Africa had serum anti-schistosome antibodies indicating recent infection. There is little doubt regarding the specificity and sensitivity of serology for the demonstration of infection, but there is a need for alternative serological methods which could be more widely used than the standard immunofluorescence assay (IFA) for antibodies against gut-derived antigens (anti-GAA). We present results suggesting that 40/42 anti-GAA positive cases also react with keyhole limpet haemocyanin (KLH), a readily available commercial antigen. High anti-GAA titres were seen for more than 2 y despite treatment with praziquantel. Thus we are faced with several questions. How likely is it that positive serology means treatment failure? What is the risk involved in chronic infection? What is the prospect for monitoring treatment outcome by serology? We conclude that there is a need for better information on the risk of becoming infected, for improved methods for testing and for monitoring the therapeutic effects in adventure tourists.
authors.affiliation: Clinic of Infectious Diseases, Västerås Central Hospital, Västerås, Sweden. cecilia.thors@smi.ki.se
authors.forename: Cecilia
authors.initials: C
authors.lastname: Thors
authors.forename: Per
authors.initials: P
authors.lastname: Holmblad
authors.forename: Mahtab
authors.initials: M
authors.lastname: Maleki
authors.forename: Johan
authors.initials: J
authors.lastname: Carlson
authors.forename: Ewert
authors.initials: E
authors.lastname: Linder
mesh_terms: D000293:Adolescent; D000328:Adult; D017954:Africa South of the Sahara; D000368:Aged; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D016903:Drug Monitoring; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006433:Hemocyanins; D006801:Humans; D008297:Male; D008875:Middle Aged; D011223:Praziquantel / Q000627:therapeutic use; D012547:Schistosoma / Q000276:immunology*; D012552:Schistosomiasis / Q000175:diagnosis* / Q000188:drug therapy / Q000276:immunology; D012698:Serologic Tests; D013548:Sweden; D014195:Travel; D016896:Treatment Outcome
chemical_list: D000909:Antibodies, Helminth; D011223:Praziquantel; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin