APHIS Monitors Highly Pathogenic Avian Influenza
The United States has the strongest avian influenza surveillance program in the world. Through our ongoing wild bird surveillance program, APHIS collects and tests large numbers of samples from wild birds in the North American flyways. It is not uncommon to detect avian influenza in wild birds, as avian influenza viruses circulate freely in those populations without the birds appearing sick. In addition to monitoring for avian influenza in wild bird populations, APHIS monitors for the virus in commercial and backyard birds.