San Diego County has not recorded a measles case since August 2025, even as multiple outbreaks elsewhere in California have pushed public health officials to urge vaccination and maintain close surveillance. CBS 8 reported March 2 that local officials said San Diego had not seen a case since last August, despite new activity in other parts of the state.

The California backdrop has grown more active. CalMatters reported that seven counties had logged 21 measles cases this year, with Shasta and Riverside counties working to contain localized outbreaks. It described the outbreaks as the state’s first since 2020.

State health officials have also warned that new cases are continuing to emerge. In a March 5 update, the California Department of Public Health said Sacramento and Placer counties had reported multiple recent cases, calling them the state’s third measles outbreak of 2026. According to CDPH, the Sacramento cluster began with an unvaccinated toddler who had recently traveled to an area of South Carolina with an ongoing outbreak. Subsequent cases were identified in children with direct exposure, and CDPH later said an educational enrichment program may have exposed as many as 130 children.

For clinicians, the San Diego lull may offer reassurance, but not complacency.

“That’s ridiculously infectious,” Dr. Sharon Balter, director of acute communicable disease control with Los Angeles County public health, told CalMatters. “It balloons very quickly, and because measles spreads very fast we have to get on it right away. We can’t say we’ll wait until tomorrow.”

California Public Health Officer Dr. Erica Pan struck a similar note, saying, “The United States is experiencing the highest numbers of measles cases, outbreaks, hospitalizations, and deaths in more than 30 years, driven by populations with low vaccination rates.” She added, “We all need to work together to share the medical evidence, benefits, and safety of vaccines to provide families the information they need to protect children and our communities.”

For San Diego practices, the recent statewide activity underscores that the county’s current stretch without a measles case is unfolding amid a more active California outbreak environment.