Avian Influenza Virus Surveillance in Wild Birds in Georgia: 2009–2011

Abstract

The Caucasus, at the border of Europe and Asia, is important for migration and over-wintering of wild waterbirds. Three flyways, the Central Asian, East Africa-West Asia, and Mediterranean/Black Sea flyways, converge in the Caucasus region. Thus, the Caucasus region might act as a migratory bridge for influenza virus transmission when birds aggregate in high concentrations in the post-breeding, migrating and overwintering periods. Since August 2009, we have established a surveillance network for influenza viruses in wild birds, using five sample areas geographically spread throughout suitable habitats in both eastern and western Georgia. We took paired tracheal and cloacal swabs and fresh feces samples. We collected 8343 swabs from 76 species belonging to 17 families in 11 orders of birds, of which 84 were real-time RT-PCR positive for avian influenza virus (AIV). No highly pathogenic AIV (HPAIV) H5 or H7 viruses were detected. The overall AIV prevalence was 1.6%. We observed peak prevalence in large gulls during the autumn migration (5.3–9.8%), but peak prevalence in Black-headed Gulls in spring (4.2–13%). In ducks, we observed increased AIV prevalence during the autumn post-moult aggregations and migration stop-over period (6.3%) but at lower levels to those observed in other more northerly post-moult areas in Eurasia. We observed another prevalence peak in the overwintering period (0.14–5.9%). Serological and virological monitoring of a breeding colony of Armenian Gulls showed that adult birds were seropositive on arrival at the breeding colony, but juveniles remained serologically and virologically negative for AIV throughout their time on the breeding grounds, in contrast to gull AIV data from other geographic regions. We show that close phylogenetic relatives of viruses isolated in Georgia are sourced from a wide geographic area throughout Western and Central Eurasia, and from areas that are represented by multiple different flyways, likely linking different host sub-populations.

Effect of biosecurity measures and early detection systems, mitigation measures and surveillance strategies on the spread of HPAI and LPAI between farms

“…( Lee et al, 2004) Territory (Lee et al, 2014) Territory Not relevant outcomes (Leibler et al, 2010) Territory (Leong et al, 2008) Territory (Lerdsamran et al, 2011) Territory (Leschnik et al, 2007) Study population (Lewis et al, 2013) Territory Study population (Li et al, 2008) Study population Territory ) Territory Not relevant outcomes ) Territory (Liao et al, 2015) Territory (Lin et al, 2006) Not relevant outcomes (Linke et al, 2011) Not relevant outcomes (Lipatov et al, 2008 The present document has been produced and adopted by the bodies identified above as authors. This task has been carried out exclusively by the authors in the context of a contract between the European Food Safety Authority and the authors, awarded following a tender procedure.…”

Influenza study of backyard animals in Georgia

“…In 2006, highly pathogenic influenza virus A/H5N1 was detected in two wild swans in Adjara (western Georgia). Moreover, in the frame of wild bird surveillance, various subtypes of influenza A viruses were detected in mallard and gulls in Georgia (Lewis, 2013). Thus domestic animals in Georgia have a potential chance to contract influenza viruses from wild birds.…”

Vigilância epidemiológica dos vírus da influenza aviária em aves migratórias na região costeira da Amazônia

“…Para tal, foi utilizada a estimativa de Pregliasco et al (1998) A prevalência aparente não foi diferente em função da ordem e família taxonômica, Alguns estudos relatam que, por esta mesma técnica, a prevalência aparente global de AIV em aves silvestres varia entre 1 e 2% (GHERSI et al, 2009;SAMBIEDA et al, 2010;GONZÁLEZ-REICHE et al, 2012;LEWIS et al, 2013). Apesar disso, sabe-se que esta prevalência pode ser bastante variável em decorrência do local de amostragem, época do ano, espécie, idade e método diagnóstico (IP et al, 2008(IP et al, , 2012GONZÁLEZ-REICHE et al, 2012 (HANSON et al, 2008;BREED et al, 2010;KRAUSS et al, 2010;LEWIS et al, 2013).…”

“…Apesar disso, sabe-se que esta prevalência pode ser bastante variável em decorrência do local de amostragem, época do ano, espécie, idade e método diagnóstico (IP et al, 2008(IP et al, , 2012GONZÁLEZ-REICHE et al, 2012 (HANSON et al, 2008;BREED et al, 2010;KRAUSS et al, 2010;LEWIS et al, 2013). Como as expedições deste estudo foram realizadas apenas durante os meses em que as aves estão chegando e saindo do Brasil, já era esperada uma prevalência similar entre estes dois períodos.…”

“…A glicoproteína H11 tem sido identificada em amostras de Charadriiformes em diferentes países com relativa frequência (HURT et al, 2006;FOUCHIER et al, 2007;KRAUSS et al, 2007;STALLKNECHT;BROWN, 2008;BORM et al, 2012;STALLKNECHT et al, 2012;LEWIS et al, 2013). Em um estudo realizado ao longo de 16…”