Natural Infection by H1-like Influenza A virus in South American Camelids from Argentina: Serological evidences.

PARREÑO, V.; ROMERO, S.; MARTÍNEZ ESCRIBANO, J.A.; BARBIERI, E.S.; PUNTEL, M.; BAUMEISTER, E.

Journal of Veterinary Health Care

Open Acces Pub

Año: 2017 vol. 1 p. 21 - 38

2575-1212

Serum samples from wild and domestic South American Camelids (SAC)from Argentina, collected before (2008), during (2009) and after (2010) the 2009 H1N1influenza pandemic were tested by hemagglutination-inhibition assay (HIA) toevaluate the seroprevalence of antibodies (Ab) against different subtypes of influenza Aviruses: A(H1N1)pdm09,A/sw/Argentina/SIV/2009(H3N2) and A/eq/Argentina/97(H3N8). For H1N1, an ELISA using a recombinantH1-hemmaglutinin from areference strain (HA0 PuertoRico/8/1934) was also conducted. Serumsamples from guanacos (126), vicugnas (21) and llamas (100) from Jujuy, Mendozaand Río Negro provinces were analyzed; noclinical signs of respiratory disease were detected, reason for which no nasalswabs were obtained. No seropositive reactors to H3N2nor H3N8 variants were detected, nevertheless high incidence of Ab reactive to A(H1N1)pdm09 were found by HIA; results which wereconfirmed by ELISA. The Ab seropositive animals to H1-like IAV found inllamas from Jujuy, and Mendoza (2009) were 78% and 86% by HIA and ELISA,respectively. Thirty-seven samples taken over the three years from guanacoskept in captivity in Rio Negro showed 62% of seropositive animals, while wildguanacos from Mendoza sampled in 2010 showed 36% seropositive animals toH1-like IAV, by both techniques. Finally,wild vicugnas from Jujuy, sampled in 2008 showed 38% and 52% seropositiveanimals to H1-like IAV by HIA and ELISA,respectively.These results suggest that SAC populations might have been infected with aninfluenza strain antigenically related to H1 IAV. Surprisingly, for llama andguanaco populations sampled over time in Jujuy and Río Negro, respectively, theHIA and ELISA geometric mean Ab titers (GMT) for 2008 were significantly higherthan the ones of 2010. In addition, HIA and ELISA Ab titers found in domestic llamaswere significantly higher than those detected in wild vicugnas sampled duringthat year (2008) in Jujuy. New field campaigns are in progress to collect serumsamples and nasal swabs in order to isolate and characterize the virusresponsible for triggering H1 reactive Abs. Thesefindings remark the need to better understand the dynamics and ecology ofinfluenza A virus within SACs population and the potential role of thesespecies as a reservoir of this zoonotic viral agent of high impact in PublicHealth.