Avian influenza virus isolated in wild waterfowl in Argentina: Evidence of a potentially unique phylogenetic lineage in South America

Abstract

Avian Influenza (AI) viruses have been sporadically isolated in South America. The most recent reports are from an outbreak in commercial poultry in Chile in 2002 and its putative ancestor from a wild bird in Bolivia in 2001. Extensive surveillance in wild birds was carried out in Argentina during 2006-2007. Using RRT-PCR, 12 AI positive detections were made from cloacal swabs. One of those positive samples yielded an AI virus isolated from a wild kelp gull (Larus dominicanus) captured in the South Atlantic coastline of Argentina. Further characterization by nucleotide sequencing reveals that it belongs to the H13N9 subtype. Phylogenetic analysis of the 8 viral genes suggests that the 6 internal genes are related to the isolates from Chile and Bolivia. The analysis also indicates that a cluster of phylogenetically related AI viruses from South America may have evolved independently, with minimal gene exchange, from influenza viruses in other latitudes. The data produced from our investigations are valuable contributions to the study of AI viruses in South America.

Migratory birds in southern Brazil are a source of multiple avian influenza virus subtypes

“…In South America, AIV has been confirmed in wild birds in multiple years in Argentina (H13N9, H1N1, H6N2, and H9N2),13, 39, 40 Bolivia (H7N3),41 (H7N3),42 Colombia (H5N2),19 Peru (H3N8, H4N5, H10N9, and H13N2),42, 43 and Brazil (H11N9) 20. However, the H6N1 subtype has not previously been identified in shorebirds.…”

Avian Influenza in Wild Birds from South America: Review, Implications and Perspectives

“…13,14 In comparison, studies in South America have found an overall prevalence of 0.21% in Anseriformes (range: 0.25-0.86%) and 0.32% in Charadriiformes (range: 0.21-3.80%) (Table 3). 33,[35][36][37][38][39][40][41][42][43][44] It is worth noting that Mathieu et al stands out among South American studies for having found a slightly higher AIV prevalence (3.8%), which is probably related to the fact that this study investigated gulls that had been found dead, as opposed to actively capturing healthy birds in their natural habitat. 36 The reasons as to why South American wild birds appear to have a lower prevalence of AIV are unclear, and future studies will be necessary to confirm whether this is a widespread pattern and identify possible causes, or to dismiss the possibility that this reflects differences in sample collection season or storage.…”

“…[39][40][41]69 However, considering the ecological and landscape diversity of the continent, it is important to also dedicate sampling effort to other areas to evaluate regional and biome-specific differences in AIV epidemiology. Additionally, valuable insight may be obtained by investigating the occurrence of AIV in wild birds in areas where there might be a closer interaction among humans, domestic and wild birds, such as swine and poultry farms, hunting grounds, and communities where subsistence hunting and domestication of wild birds is common practice.…”

Presencia Del Virus De Influenza Aviar en Aves Silvestres De Los Humedales De Puerto Viejo, Lima

“…Resultados similares han sido observados en Argentina en muestras de hisopados cloacales de aves silvestres donde se detectaron 12 (12/2495) muestras positivas al virus de IA mediante la técnica de rRT-PCR, reportándose, además, el aislamiento de un virus del subtipo H13N9 de una gaviota (Larus dominicanus) (Pereda et al, 2008). Asimismo, de 93 muestras de hisopados cloacales de 11 especies de aves silvestres colectadas en Bolivia en el 2001 se logró aislar una cepa de virus del subtipo H7N3 de una cerceta colorada (Anas cyanoptera) (Spackman et al, 2007).…”