H5N1 Poultry Vaccination in Egypt Will Not Stop the Spread of the Virus

Influenza A(H5N1) can still be considered a novel infectious disease even though it has been infecting people since 1999.  As of July, 2013,  more than 600 people around the world have been infected with H5N1.[1] Of these, more than half have died. If you are infected, it is a deadly disease.

A review of H5N1 case descriptions reported by the World Health Organization (WHO) almost always identifies the source of the infection as sick or dying poultry. In countries where H5N1 is endemic, vaccination of poultry is a strategy used to control the spread of H5N1.

In an article by El Masry and colleagues in Tropical Animal Health and Production published earlier this month, the authors  discusses the effectiveness of vaccinating poultry in Egypt against H5N1. [2]

The key observation by these researchers: 

Despite the enormous effort put into rural house-hold poultry AI vaccination by the Egyptian government, village CAFI [a measure of flock immunity] is unlikely to be maintained at the levels required to significantly reduce the virus load and restrict transmission. Reducing HPAI H5N1 viral load and transmission requires maintenance of high levels of flock immunity. This will require massive additional financial means, and it is questionable if it can be logistically feasible.

The authors conclude that current H5N1 poultry vaccination strategies in Egypt will be unsuccessful in controlling the virus load and transmission within local poultry flocks.  We can expected more human cases of H5N1 in Egypt from sick and dying poultry.

[1] http://www.who.int/influenza/human_animal_interface/Influenza_Summary_IRA_HA_interface_03July13.pdf

 

[2] Modelling influenza A H5N1 vaccination strategy scenarios in the household poultry sector in Egypt. http://link.springer.com/content/pdf/10.1007%2Fs11250-013-0446-8.pdf