And the government is doing a “very spotty” job of monitoring for dangerous strains of swine flu.

In March of 2009, people in the rural Mexican village of La Gloria started coming down with a nasty respiratory infection. The town, located in the state of Veracruz, sat 5 miles from an industrial-scale hog farm. Within a few weeks, clusters of this rapidly progressing pneumonia arose among Mexico City residents. Researchers soon identified the bug as a “novel swine flu.” It quickly jumped to the United States and spread worldwide, and in June, the World Health Organization declared a pandemic, the first time it had done so since the deadly avian flu outbreak of 1968.

The 2009 swine flu strain didn’t turn out to be as deadly as originally feared. Although indeed novel, it was similar enough to older flu strains that about a third of people over 60—the most vulnerable population—had preexisting antibodies to the virus, helping them shake it off. Even so, it killed more than 284,000 people around the world, including at least 12,469 Americans.