Experimental Infection of Chickens with Intercontinental Reassortant H9N2 Influenza Viruses from Wild Birds.
The H9N2 subtype of low pathogenic avian influenza (LPAI) virus is the most prevalent LPAI in domestic poultry. We previously reported the natural reassortant H9N2 viruses between North American and Eurasian lineages isolated from wild birds in Korea. These viruses were identified in China and Alaska, providing evidence of intercontinental dispersal. In this study, we evaluated the infectivity, transmissibility, and pathogenic potential of these H9N2 viruses and Eurasian H9N2 virus identified from wild birds using specific-pathogen-free chickens. Three-week-old chickens were infected intranasally. All of these reassortant H9N2 viruses could not be replicated and transmitted in chickens. On the other hand, three out of eight chickens inoculated with the Eurasian H9N2 virus shed detectable levels of virus and showed seroconversion but did not show contact transmission of the virus. Although all reassortant H9N2 viruses could not be replicated and transmitted in chickens, and although there are no reports on reassortant H9N2 virus infection in poultry farms until now, monitoring of reassortant H9N2 viruses should be continued to prepare for the advent and evolution of these viruses.
Avian Disease Laboratory, College of Veterinary Medicine, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701, Republic of Korea.
Dong-Hun
DH
Lee
Avian Disease Laboratory, College of Veterinary Medicine, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701, Republic of Korea.
Jung-Hoon
JH
Kwon
Jae-Keun
JK
Park
Seong-Su
SS
Yuk
Erdene-Ochir
EO
Tseren-Ochir
Jin-Yong
JY
Noh
Joong-Bok
JB
Lee
Seung-Yong
SY
Park
In-Soo
IS
Choi
Chang-Seon
CS
Song
D000818:Animals; D000835:Animals, Wild; D002645:Chickens; D053127:Influenza A Virus, H9N2 Subtype / Q000472:pathogenicity* / Q000502:physiology*; D005585:Influenza in Birds / Q000635:transmission / Q000821:virology*; D011201:Poultry Diseases / Q000635:transmission / Q000821:virology*; D016865:Reassortant Viruses / Q000472:pathogenicity / Q000502:physiology; D013047:Specific Pathogen-Free Organisms
H9N2; avian influenza virus; chicken; wild bird