The subject line on the email read: "Extremely Important -- P.1 Variant Identified in Bay County."
"This is the first of this variant identified in Michigan to date," read the message, dated March 31 and sent from Melanie Perry, an epidemiologist at the Michigan health department, to Bay County health officials.
Believed to be about two times more contagious than earlier strains of COVID-19, the P.1 coronavirus variant originated in the Amazon in November 2020.
It's a concern not only because it's more contagious, but also because monoclonal antibody treatments are less effective in people with the P.1 variant, which has 17 unique mutations. The strain also is known to reinfect people who've already had COVID-19, studies have shown.