Chlamydiaceae in North Atlantic seabirds admitted to a wildlife rescue centre in Western France
Birds are the primary hosts of Chlamydia (C.) psittaci, a bacterium that can cause avian chlamydiosis in birds and psittacosis in humans. Wild seabirds are frequently admitted to wildlife rescue centres (WRC) at European Atlantic coasts, for instance in connection with oil spills. To investigate the extent of chlamydial shedding by these birds and the resulting risk for animals in care and the medical staff, seabirds from a French WRC were sampled from May 2011 to January 2014. Using a quantitative PCR, 195 seabirds belonging to 4 orders, 5 families and 13 species were examined, of which 18.5 % proved Chlamydiaceae positive. The highest prevalence of shedders was found in Northern gannets (Morus bassanus) (41%), followed by European herring gulls (Larus argentatus) (14%) and Common murres (Uria aalge) (7%). Molecular characterisation and phylogenetic analysis of qPCR-positive Northern gannet samples revealed two variants of a strain closely related to C. psittaci. In European herring gulls and in one Common murre, strains showing high sequence similarity to the atypical Chlamydiaceae-like C122 previously found in gulls were detected. Our study highlights that seabirds from the north-eastern Atlantic Ocean are carrying several chlamydial organisms, including C. psittaci-related strains. The staff in WRCs should take protective measures, in particular in case of mass admissions of seabirds.