Gov. Gavin Newsom calls COVID-19 herd immunity ‘illusory.’ Is he right?

Andrew Noymer, an epidemiologist and [associate professor] population health at UC Irvine, noted that herd immunity isn’t the same as disease eradication, as occurred with smallpox through a global vaccination campaign. With herd immunity, there still will be infections, even small outbreaks, as there are with measles. They just won’t spread far. … UC Irvine’s Noymer said it’s likely we won’t know when we’ve reached herd immunity until months after the fact, and, even then, it may be temporary.