Revision History

A strain of norovirus called GII.17 has rapidly displaced the previously dominant GII.4 genotype, now accounting for 75% of U.S. outbreaks and driving widespread illness that wastewater data shows remains at high levels across most of the country. While the CDC says total outbreak counts fall within historical norms, the strain shift, fragmented surveillance infrastructure, and a $10.6 billion annual economic burden raise questions about whether the nation's monitoring systems are adequate for a virus that sickens roughly 21 million Americans each year.