Evidence for a permanent presence of schistosomiasis in Corsica, France, 2015

Antoine Berry, Judith Fillaux, Guillaume Martin-Blondel, Jérôme Boissier, Xavier Iriart, Bruno Marchou, Jean François Magnaval, Pierre Delobel
2016 Eurosurveillance  
We present a case of acute schistosomiasis acquired in Corsica after bathing in the Cavu River during the summer of 2015. The diagnosis was made following epidemiological, laboratory and serological assessments. After a previous outbreak of urogenital schistosomiasis during the summer of 2013, when more than 120 infections were diagnosed, this further case indicates transmission was still effective in 2015, thus suggesting a permanent presence of schistosomiasis in Corsica. We report a case of
more » ... chistosomiasis acquired in 2015 in Corsica, indicating that permanent transmission of this helminthiasis has been established on the island. Case description On 11 September 2015, a person in their 40s presented to the Consultation Board at the Infectious and Tropical Disease Department of Toulouse University Hospitals in France with a 15-day history of diffuse abdominal pain, headache and asthenia. The patient had no fever, and physical examination was unremarkable. In particular, the patient neither displayed any skin rash nor complained of pruritus. The white blood cell count was 6.0 × 10 9 /L, within the normal range (4.0-10.0 × 10 9 cells/L), but a blood eosinophilia (3.2 × 10 9 cells/L, normal range: < 0.5 × 10 9 cells/L) was observed by differential count. Biochemical tests of liver function found several abnormalities, namely a serum alanine aminotransferase level at 140 UI/L (normal range: 0-40 UI/L) and a gamma-glutamyl transferase level at 323 IU/L (normal range: 0-60 IU/L). Aspartate aminotransferase and total bilirubin levels were within the normal range. C-reactive protein was 11.7 mg/L (normal value: < 5 mg/L). By serology, the patient tested negative for cytomegalovirus, Epstein-Barr virus, hepatitis A, B and C, and Leptospira infections. Serodiagnostics of ascariasis, alveolar and cystic echinococcoses, fascioliasis, filariases, strongyloidiasis, trichinellosis and schistosomiasis were negative. The ELISA result for schistosomiasis (expressed as a ratio), although negative with a ratio of 0.770, was close to the cut-off value of 1.0. Schistosomiasis serology relied upon commercial ELISA kits (Bordier Affinity Products, Crissier, Switzerland) and indirect haemagglutination assay (IHA) (Fumouze Diagnostics, Levallois-Perret, France), which are both screening tests using Schistosoma mansoni extracts as antigen. Because an aetiological diagnosis was not reached, the patient attended a further consultation on 24 September. The clinical picture remained unchanged, but blood eosinophilia decreased to 2 × 10 9 cells/L. By that time, specific laboratory examinations for urogenital schistosomiasis had been carried out because of the previous ELISA result and also because the patient informed us of their vacation in Corsica in summer 2015. Urinalysis was normal, and microscopic search for Schistosoma haematobium eggs remained negative. Serology was positive, with an ELISA ratio of 2.65 (cutoff: 1.0). The IHA result (expressed as a titre of dilution) was 160 (cut-off: 160). These results were checked by a commercial Western blot using a mixture of adult S. haematobium and S. mansoni antigens (SCHISTO II Western blot IgG, LDBIO Diagnostics, Lyon, France). Faintly positive bands were observed at 30 kDa and 34 kDa, a result which was specific for the Schistosoma genus. On 15 October, the patient was asymptomatic, the eosinophil count had decreased to 0.5 × 10 9 cells/L and hepatic tests were back to normal values. The level of Schistosoma-specific antibodies, as measured by ELISA (ratio: 4.67) or IHA (titre: 320) had increased.
doi:10.2807/1560-7917.es.2016.21.1.30100 pmid:26767427 fatcat:3ylqdek5mzeujbtgl7p6l2nl24