Prevalence of avian influenza viruses, Mycobacterium avium, and Mycobacterium avium, subsp paratuberculosis in marsh-dwelling passerines in Slovakia, 2008

Prevalence of the infectious respiratory agens, avian influenza virus (AIV), Mycobacterium avium (M. avium), and Mycobacterium avium subspecies paratuberculosis (MAP), was studied in migratory marsh-dwelling passerines captured in the Parizske mociare wetlands in Western Slovakia during 2008. Surveillance of 650 birds revealed a lower prevalence of AIV in spring (13.6%) than in summer (17.5%). A total of 14 different subtypes were detected in samples obtained from birds captured during the spring, with the most prevalent subtypes being H8N3, H6N4, H11N6 and H12N6. Subtypes H12N6, H6N6 and H2N5 were predominant in passerines captured during summer months. In eight cases, different AIV infections were detected in the oropharyngeal and cloacal samples originating from a single bird (H1N1 and H8N3; H1N3 and H9N3; H2N3 and H12N6; H2N1 and H8N1; H4N2 and H9N6; H5N5 and H11N6; H6N4 and H11N6; H7N1 and H10N3 in the oropharynx and cloaca, respectively). M. avium was detected in 9.2% and 0.8% of marsh-dwelling passerines captured during spring and summer, respectively. Only two birds were co-infected with AIV and M. avium. All birds were negative for MAP.