Title: Cross-clade immunity in cats vaccinated with a canarypox-vectored avian influenza vaccine Authors
|Stittelaar, Koert -|
|Lacombe, Valerie -|
|Van Lavieren, Rob -|
|Van Amerongen, Geert -|
|Simon, James -|
|Cozette, Valerie -|
|Poulet, Herve -|
|Osterhaus, Albert -|
Submitted to: Vaccine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 11, 2010
Publication Date: July 12, 2010
Citation: Stittelaar, K.J., Lacombe, V., Van Lavieren, R., Van Amerongen, G., Simon, J., Cozette, V., Swayne, D.E., Poulet, H., Osterhaus, A.D. 2010. Cross-cloade immunity in cats vaccinated with a canarypox-vectored avian influenza vaccine. Vaccine. 28(31):4970-4976. Interpretive Summary: Cats are susceptible to H5N1 high pathogenicity avian influenza (HPAI) virus. A biotechnologically advanced vaccine, a recombinant canary poxvirus vaccine with H5 avian influenza hemagglutinin gene, was developed and tested in house cats against two H5N1 HPAI viruses. The vaccine protected the cats against mortality, reduced severity of lung changes, and decreased challenge virus growth and shedding. This vaccine protected cats against H5N1 HPAI virus challenges and could reduce the risk of virus transmission.
Technical Abstract: Several felid species have been shown to be susceptible to infection with highly pathogenic avian influenza (HPAI) viruses of the H5N1 subtype. Infection of felids by H5N1 HPAI virus is often fatal, and cat-to-cat transmission has been documented. Domestic cats may then be involved in the transmission of infection to other animals, but also to humans. A particular concern is the hypothetical role of the cat in the adaptation of the virus to mammalian species, thus increasing the pandemic risk. Therefore, the development of a HPAI vaccine for domestic cats should be considered a veterinary and also a public health priority. Here we show that vaccination of cats with a recombinant canarypox (ALVAC) virus, expressing the hemagglutinin (HA) of influenza virus A/chicken/Indonesia/03 (H5N1) confers protection against challenge infection with two antigenically distinct H5N1 virus isolates from humans. Despite low hemagglutination inhibiting (HI) antibody titers at the time of challenge, all vaccinated cats were protected against mortality and had reduced histopathological changes in the lungs. Importantly, viral shedding was reduced in vaccinated cats as compared to controls. Since the recombinant canarypox (ALVAC) virus not only protected cats against homologous and heterologous H5N1 HPAI virus challenges, it may be concluded that vaccination of cats could reduce the risk of viral transmission.