21 August 2009

Chile re= ports turkeys infected with human pandemic influenza virus H1N1/2009

Today the World Organization for Animal Health (Organization International Epizootic (OIE))= reported an “immediate notification” on their website (www.oie.int/eng/en_index.htm) that Chile has reported the first known infection of an avian species (turkeys) with t= he human pandemic H1N1/2009 influenza virus (formerly referred to as “sw= ine flu” in April 2009). The source of the infection is listed currently on the OIE website as “Unknown or inconclusive”, although they also report that “prior to the appearance of clinical signs, some birds were exposed to people showing respiratory symptoms”.

The specific laboratory tests reported to the OIE as positive included: real-time PCR on August 20^th (with virus sequencing pending today), performed at = the Chilean Public Health Institute (National laboratory); as well as the neuraminidase inhibition assay (on 19 August), haemagglutination inhibition test (HT) (also on 19 August), agar-gel immunodiffusion (AGID) (on 15 Augus= t), and antibody detection by ELISA (on 14 August). These latter four tests were performed at the Lo Aguirre Laboratory and quarantine station (National Laboratory), according to the OIE posting.= In addition, “Samples will be sent to the OIE Reference Labora= tory”.

There were two outbreaks reported in Chile. One began 23 July 2009 at Las Palmas, Quil= pue, Valparaiso, VALPARAISO and involved breed= ing turkeys which “presented a drop from 70% to an average of 31% and a reduction in the quality of the shell”. Neither respiratory signs nor incr= eased mortality were observed. Necropsy showed salpingitis, peritonitis, and an interruption of the follicular development. No other lesions were observed.”

The 2^nd outbreak began 29 July in Pucalan, Quillota, Nogales, <= st1:City w:st=3D"on">VALPARAISO. Again, the “birds are breeding turkeys showing an abnormal decrease in the laying rate. Neither respiratory signs nor increased mortality were observed.” <= /span>

Taken together, t= hese two outbreaks posted by the OIE were notable for no (i.e., zero) “apparent mortality rate”, “apparent case fatality” rate, and zero animals lost to death, destruction and/or slaughter”. =

Follow-up epidemiological and virological investigations = of this novel infection of an avian species are anticipated soon. <= /span>

So far, there is = no evidence of any individual humans, swine, or avians (e.g., turkeys) having dual infection with the pandemic H1N1/2009 virus and= any H5 or H7 virus; however, one could expect increased surveillance for this pandemic virus in other turkey and avian populations worldwide.

Reports appeared = today in the media (e.g., Reuters) and on the ProMed-= mail website. The Reuters article reported that the location of the two outbreak= s is 120km west of Santiago, the ca= pital.

The virologic sequencing and antiviral susceptibility test results can also be anticipated soon, as well as test results for humans who had been present on these turkey farms recently.

The absence of any respiratory symptoms, or any lung involvement at the initial necropsies, is also noteworthy as this story unfolds.

Daniel R. Lucey, MD, MPH

EROne Insitutes, Department of Emergency Medicine

Washingt= on Hospital Center

Georgeto= wn University = Medical Center

Washingt= on, DC

DRL23@Georgetown= .edu

Website for this posting (www.BePast.org (requires IE)