An epizootic of highly pathogenic avian influenza virus H7N3 in a Mexican ecological reserve.

In this case study, we describe an outbreak of highly pathogenic avian influenza (HPAI) virus subtype H7N3 in an ecological reserve in Chiapas, Mexico, affecting captive and wild birds. The virus was detected mainly in plain chachalacas displaying respiratory and gastrointestinal clinical signs and death within 24 hours. Mortality in white-fronted parrots and a clay-colored thrush was also recorded. We describe control strategies implemented to prevent virus dissemination and active surveillance within the risk area. Phylogenetic analysis revealed that the HPAI H7N3 virus detected in affected birds shared a close genetic relationship with Mexican H7N3 isolates from 2012.