MEXICO - Five new outbreaks of H7N3 highly pathogenic avian influenza (HPAI) have affected almost 900,000 birds across three states.

The veterinary authority has sent Follow Up Report No. 7 dated 7 May to the World Organisation for Animal Health (OIE).

The report describes five new outbreaks of HPAI of the H7N3 subtype starting between 1 March and 1 May 2013. More than 890,000 birds were involved; there were 75,011 cases, of which 40,010 birds died and 850,005 were destroyed.

Two outbreaks were in each of the previously affected states of Jalisco and Guanajuarto and one was in Puebla. One of the Jalisco outbreaks was in a village flock but the other four were on farms.

Two new outbreaks were identified in Jalisco: one in a commercial layer farm in Tepatitlán de Morelos and another in a backyard farm in the municipality of San Diego de Alejandría. In Guanajuato, two outbreaks were detected: one in a heavy breeder flock in Dolores Hidalgo and another in a fattening farm in the municipality of San José Iturbide.

Moreover, a new outbreak was identified in a commercial layer farm in the municipality of Palmar de Bravo, Puebla. It was confirmed by the National Reference Laboratory using virus isolation on 6 May 2013. On 7 May, the farm was depopulated and control measures including cleaning and disinfection of facilities and equipment as well as sampling around the outbreak within a 10-km radius were launched, in addition to epidemiological surveillance at State level.

All these outbreaks are described as "resolved".

The report adds that, in response to an outbreak, more than 5.5 million birds on commercial breeder and layer farms have been vaccinated.