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Annecy Lake is a well-known focus of human cercarial dermatitis in France. Identification of the parasites, however, was not performed in the past. Previous studies suspected two species, Trichobilharzia franki and Trichobilharzia regenti, based on the presence of parasites in mallards and/or morphological identification of snails emitting ocellate furcocercariae. Following a standardized molecular approach, we studied snails and furcocercariae and compared their haplotypes with those deposited in GenBank. The selected markers were the second internal transcribed spacer ITS-2 for the snails and ITS-2 and D2 domain of the ribosomal DNA for the parasites. Our results confirm the presence of T. franki and T. regenti and two probable new species that could be potential agents of cercarial dermatitis. All the snails emitting the ocellate furcocercariae belong to the same species identified as Radix peregra (=Radix ovata = Radix balthica). Parasite-host relationships between species of the genus Trichobilharzia and snails of the genus Radix do not seem to be as specific as supposed previously.

In 1998, the description of Phlebotomus riouxi emphasised the difficulty to differentiate the female from the closely related P. chabaudi, a suspected vector of Leishmania killicki in several foci in Tunisia. In order to be able to distinguish the females of these two species, we started a molecular study based on 37 Algerian and Tunisian specimens. The alignment of the sequences of the cytochrome b of the mitochondrial DNA and their analysis using Neighbor-Joining, maximum likelihood and maximum parsimony shows the individualisation of two species including an intraspecific variability. Following a morphological approach, it is not possible to distinguish the females on the basis of their spermathecae. A new character is proposed: the presence of antero-lateral teeth of the pharyngeal armature for P. chabaudi, never observed in P. riouxi. However, a molecular typing is necessary at the present time for a sure identification of the females. Résumé

The prevalence of human cercarial dermatitis (HCD) caused by bird schistosomes appears to be increasing in France, in light of the impact of tourism combined with high densities of wild aquatic hosts in freshwater areas. The present work expands our knowledge of schistosome systematics by including samples of bird schistosomes collected from their natural hosts in France. Heads (318) and viscera (81) of aquatic birds belonging to 16 species from five orders, collecting during the hunting seasons or found dead, were autopsied for nasal and visceral schistosomes. Eggs and/or adults were analysed by molecular methods using the D2 domain and the second internal transcribed spacer (ITS-2) region of rDNA to determine species. Even if nasal eggs were polymorphic according to the host, all haplotypes were similar to that of Trichobilharzia regenti. Marked diversity of visceral species was observed. Final hosts under natural conditions were reported. For the first time, Trichobilharzia franki is reported in its natural bird hosts, Anas platyrhynchos, Anas crecca, Aythya fuligula and Cygnus olor. We also identified T. szidati in A. crecca and Anas clypeata. Bilharziella polonica was found in six species of aquatic birds, including Grus grus. This finding is the first record of bird schistosomes in this aquatic bird. Three new taxa of visceral schistosomes in Anser anser are strongly suspected according to their haplotypes. Futhermore, a new haplotype of visceral schistosomes isolated in Cygnus olor and similar to Allobilharzia visceralis was identified.