title: Modelling influenza A H5N1 vaccination strategy scenarios in the household poultry sector in Egypt.
abstract: Highly pathogenic avian influenza (AI) due to H5N1 virus was first reported in Egypt in February 2006; since then, the government has allowed avian influenza vaccination in poultry. The present study evaluated the impact of AI vaccination in terms of cumulative annual flock immunity (CAFI): the percentage of bird × weeks protected by immunity. This evaluation took account of the combined effects of vaccination coverage, vaccine efficacy (VE), and different characteristics of household poultry production on the effectiveness of the adopted vaccination strategy (VS), and provided alternative options for improvement. The evaluation used a population and vaccination model that calculates the CAFI. Participatory approaches were employed in 21 villages to develop the vaccination and flock parameters required for the model. The adopted VS were compared in the model with three alternative VS scenarios in terms of the CAFI. Vaccination coverage varied among villages but was generally low (between 1 and 48 %; median 14 %). Under the adopted VS, the CAFI predicted for the villages ranged from 2 to 31 %. It was concluded that despite the enormous effort put into rural household poultry AI vaccination by the Egyptian government, village CAFI is unlikely to be maintained at the levels required to significantly reduce the virus load and restrict transmission. In HPAI-endemic countries that consider AI vaccination as one of the disease control options, the high cost of mass AI vaccination campaigns and their achievable benefits must be compared with other available control measures, which may include targeted vaccination. Achievable vaccination coverage, VE and the different characteristics of commercial and household (village) poultry production are key parameters determining the feasibility and cost-effectiveness of different AI vaccination strategies.
authors.affiliation: Emergency Centre for Transboundary Animal Disease, Food and Agriculture Organization of the United Nations (FAO), P.O. Box 2223, Cairo, Egypt, ihab.elmasry@fao.org.
authors.forename: Ihab
authors.initials: I
authors.lastname: El Masry
authors.forename: Jolianne
authors.initials: J
authors.lastname: Rijks
authors.forename: Marisa
authors.initials: M
authors.lastname: Peyre
authors.forename: Nick
authors.initials: N
authors.lastname: Taylor
authors.forename: Juan
authors.initials: J
authors.lastname: Lubroth
authors.forename: Yilma
authors.initials: Y
authors.lastname: Jobre
mesh_terms: D000822:Animal Husbandry; D000818:Animals; D004534:Egypt / Q000453:epidemiology; D053124:Influenza A Virus, H5N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines; D005585:Influenza in Birds / Q000453:epidemiology / Q000517:prevention & control* / Q000821:virology; D032541:Mass Vaccination / Q000662:veterinary; D008954:Models, Biological; D011200:Poultry; D011201:Poultry Diseases / Q000453:epidemiology / Q000517:prevention & control* / Q000821:virology; D014611:Vaccination / Q000662:veterinary*
chemical_list: D007252:Influenza Vaccines