Before Even Receiving a Name, Omicron Could Have Spread in New York and the Country

A health care analyst came to Manhattan for an anime convention. His trip shows how the virus once again outpaced the public health response.

They wore fluorescent wigs and capes with gold tassels. They arrived in knee-high white platform boots, and with feathered wings affixed to their backs. Dressed like their favorite characters, or just wearing street clothes, they packed into Manhattan’s main convention hall — some 53,000 of them — over three days in November to celebrate their love of Japanese animation shows known as anime.

In the crowd was Peter McGinn, a 30-year-old health care analyst in town from Minneapolis. He attended discussion panels, chatted with strangers about his anime podcast and, at night, sang karaoke with friends. After flying home, he learned that one friend from the convention — an anime fan from North Carolina — had just tested positive for the coronavirus. In the days to come, many more of his friends from the convention would test positive, as well. Coughing and feeling tired, Mr. McGinn also took a test. He had the virus, too.

That was Nov. 23, a day before most scientists had even heard of the new variant that was tearing across southern Africa. The World Health Organization had not yet even given the variant a name — Omicron. But it was already present in the United States, undetected.