Do Canada geese (Branta canadensis Linnaeus, 1758) carry infectious agents for birds and man?

Abstract

Currently, large groups of Canada geese (Branta canadensis Linnaeus, 1758) aggregate in recreational areas of north-western Germany. Questions have arisen as to whether these birds represent a special risk factor as a source of zoonotic agents for humans and as a source of viruses, causing notifiable or reportable diseases, for domestic poultry and waterfowl. To answer these questions, a total of 289 eggs were collected in 2002 and 2003 on a recreation site and assayed. Chlamydia psittaci was not isolated and neither was chlamydial antigen detected by polymerase chain reaction. All virus-isolation attempts were unsuccessful. Neither Salmonella spp. nor Campylobacter spp. was isolated from embryonic tissues, chorioallantoic membranes or yolk-sac membranes. The presence of antibodies against Newcastle disease virus and influenza A virus (haemagglutinin subtypes H5 and H7) was demonstrated in egg yolk. Antibodies were also detected against the egg-drop syndrome 1976 and duck plague viruses. It is concluded that further surveillance studies are needed for a reliable risk assessment. Keywords Bacterial zoonotic agents AE Hepatitis B virus AE Influenza A virus of the HA subtypes H5 and H7 AE Duck plague virus AE Egg-drop syndrome 1976 virus

Dynamics and ecological consequences of avian influenza virus infection in greater white-fronted geese in their winter staging areas

“…Mean virus prevalence in the first two seasons was low and in the range of findings for other goose species (Bonner et al 2004;Jonassen & Handeland 2007;Munster et al 2007). The average prevalence of 10.7 per cent in the 2007 -2008 season is among the highest AI virus prevalence reported thus far for a species outside the genus Anas.…”

Antibodies to Avian Influenza Viruses in Canada Geese (Branta canadensis): A Potential Surveillance Tool?

“…The detection of antibodies in hatch-year birds sampled in June and July was unexpected, especially in southern locations where geese have been consistently negative by virus isolation (Harris et al, 2010). These positive results could have resulted from a very low level of transmission during late spring and early summer or passive transfer of antibodies as described in gulls and geese (Bö nner et al, 2004;Velarde et al, 2010). The local variation in antibody prevalence we detected should be analyzed with caution because some flocks undergo molt migrations (Dieter and Anderson, 2009) and other movements (Dunton and Combs, 2010) that can affect exposure in geese.…”

Morphometric and allometric studies on eggshells and embryos of free-living Canada geese (Branta c. canadensis Linnaeus, 1758)

“…At least some of them can be attributed to infections by bacteria and fungi that penetrated the shells (Bo¨nner et al 2003). Lethal, egg-transmitted viral infections were not recorded in a subsequent study (Bo¨nner et al 2004).…”

“…Subsequently, internal organs were removed and examined macroscopically for lesions and thereafter transferred for bacteriological, mycological, and virological examinations as decribed elsewhere (Bo¨nner et al 2004).…”

“…The yolks of these eggs were used to monitor the current status of infection of geese because (1) the antibody status provides information on previous infections, (2) the antibody levels in yolk and serum are almost identical, (3) the collection of eggs is considered less harmful than trapping of breeding geese for blood sampling and (4) breeding geese that have lost their eggs tend to produce a second clutch. The obtained serological and microbiological results are described in a separate paper (Bo¨nner et al 2004).…”