Development of a novel method for avian surveillance of zoonotic infectious diseases and its application on domestic chickens and wild birds in Israel

Lilach Friedman ^1,2 Amit Kahana ^1,2 Elior Adaoui ^1,2 Nir Rudoler ^1,2,3 Tomer Hertz ^1,2,4

¹The Shraga Segal Department of Microbiology, Immunology and Genetics, Ben-Gurion University of the Negev, Israel
²National Institute of Biotechnology in the Negev, Ben Gurion University of the Negev, Israel
³Veterinary Unit, Food Safety Authority, Ministry of Health, Israel
⁴Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, USA

Many infectious diseases are spread through zoonotic transfer between wild and domestic animals and humans, and are one of the leading causes of mortality worldwide. The recent increase in human epidemics caused by infectious diseases in birds, such as avian influenza or West-Nile viruses in wild birds and chickens, highlights the need to identify zoonotic pathogens in birds before they are transmitted to humans.

We developed an antigen microarray spotted with 85 recombinant proteins of 68 influenza strains from 19 subtypes, as well as recombinant proteins of 9 flaviviruses, including West-Nile virus (WNV), to longitudinally characterize the development of anti-influenza and anti-flaviviral antibodies in domestic chickens and wild birds.

We studied broiler and heavy breeding chickens from four different coops. Dried blood spots on Whatman paper and tracheal swab samples were collected from young chicks before and after H9N2 avian influenza vaccination. Serum samples were also collected post vaccination.

Post vaccination, we successfully detected a specific rise of anti-H9N2 IgY and IgM antibodies in the blood and serum, and anti-H9N2 IgA antibodies in tracheal swab samples. We also identified exposures to H5N1 avian influenza and WNV in part of the coops, although no symptomatic disease was reported. Anti-WNV antibodies were detected in samples collected on July 2018, just before the August 2018 WNV outbreak in humans in Israel.

Our results highlight the importance of serological surveillance of zoonotic diseases in Israel and the utility of our novel arrays to detect asymptomatic exposures of such diseases.