ECDC rapid risk assessment: Human cases of swine influenza without apparent exposure to pigs, United States and Mexico

Risk assessment

On April 21, the United States reported on the existence of 2 human cases of swine influenza A (H1N1) infection. On 23 April, through intensified surveillance efforts, a total of 7 confirmed human cases of swine influenza A (H1N1) infection, were reported.