Occurrence of Avian Influenza H5N1 among Chicken, Duck Farms and Human in Egypt

Avian influenza (AI) H5N1 virus consider a potential threat to the poultry industry with sever zoonotic effect associated with a high risk on human being associated with the poultry production. The disease become endemic in Egypt and cause more than 359 confirmed human infection cases in the last few years. Samples (serum and tissues) collected from 160 poultry farms that suspected to be infected with H5N1. Samples were collected from 75 broiler chicken farms, 55 broiler duck farms and 30 layer duck farms. As well as 115 human samples (serum and throat swabs) collected from persons suffering from respiratory manifestations and have a history of contact with infected birds. Samples were examined using Haemagglutination inhibition (HI) test and Reverse Transcription Real Time PCR (RT- qPCR) for detection of avian influenza H5N1 virus. HI test detect H5N1 antibodies in 71 poultry samples out of 160 (44.4%). While, RT- qPCR detect H5N1 in 13 out of 160 samples (8.1%). On the other hand, HI test detect H5N1 antibodies in six human sample out of 115 human cases (5.2%) while, RT- qPCR detect H5N1 in two human samples out of 115 human cases (1.7%). There was an increase in rate of highly pathogenic avian influenza transmission from poultry-to-human. Adaption of AI virus was increased to duck flocks with higher percentage of vaccinal escape. Thus, there is a need to give more attention to the vaccination programs and increasing the usage of the vaccines prepared from Egyptian H5N1 virus or update the current vaccines with the isolates representing the circulating virus in the Egyptian market. All these measures will increase the protection level in poultry farms and intern decrease the risk of human infection rates.