Health & Fitness

Signs Of Measles Outbreak Alarm CA Health Officials

As of June 1, the confirmed measles cases have nearly doubled compared with 25 cases reported last year.

Corey Washington, Patch StaffVerified Patch Staff Badge
|

SACRAMENTO, CA — Health officials raised alarms this week after wastewater samples again showed measles spreading in California as the state continues to see the highest number of measles cases in seven years.

California health officials, however, are already grappling with 49 confirmed cases of measles as of June 1. The confirmed cases have jumped compared with 25 cases reported in 2025. Most of the confirmed cases were people were not vaccinated or had whose vaccination status was unknown.

The Merced County Department of Public Health announced on Friday, that the measles virus was detected in wastewater samples routinely tested in the county.

Find out what's happening in Across Californiafor free with the latest updates from Patch.

No new clinical cases have been confirmed in connection with the finding.

Measles is a highly contagious virus that can easily infect a person who is unvaccinated. According to the Mayo Clinic, measles, also called rubeola, used to be a common childhood illness. Most people who contract measles usually recover in about 10 days. Though the disease is preventable, measles can be serious and is potentially deadly, especially for children under the age of 5, and those living with a weakened immune system.

Find out what's happening in Across Californiafor free with the latest updates from Patch.

Measles causes a blotchy rash that can be shades of red, purple or brown depending on a person's skin color. The rash usually appears on the face and behind the ears, and spreads to the rest of the body, according to the Mayo Clinic.

Vaccinations have made measles uncommon in the United States for more than two decades, according to the Mayo Clinic, but the U.S. has seen a rise in measles cases health officials have attributed to vaccine hesitancy.

In 2000, U.S. health officials declared measles eliminated in the U.S. But last year, the disease made a resurgence with CDC data confirming 2,255 measles.

Dr. Monica Gandhi, an infectious disease expert at the University of California, San Francisco, said because measles is easy to contract, devastating outbreaks can occur in a setting of low immunity.

"In the U.S., we are in the midst of the largest measles outbreak in the United States in 25 years," said Dr. Gandhi. "The rate of hospitalization for these measles cases was 11 percent and there were three deaths from measles in 2025."

Dr. Gandhi also noted vaccination coverage among U.S. kindergartners has decreased from 95.2 percent during the 2019–2020 school year to 92.5 percent in the 2024–2025 school year.

"Moreover, a full out assault on vaccine recommendations during the first year of this administration is contributing to even lower vaccine confidence. There were 48 outbreaks reported in 2025, and 90 percent of confirmed cases (2,065 of 2,288) were outbreak-associated," she added.

She said the disease manifestations are worse in malnourished children and patients with defective cell-mediated immunity.

The Centers for Disease Control and Prevention (CDC) said outbreaks continue to occur when travelers who are infectious cross into communities with low vaccination rates.

There is no effective treatment for measles.

According to the CDC, two doses of measles, mumps, and rubella (MMR) vaccine provide the best protection against measles.

The CDC said MMR is safe and effective, and very rarely cause extreme reactions. Two doses of MMR vaccine is about 97 percent effective at preventing measles; one dose is about 93 percent effective.

The CDC advises the public to discuss the MMR with their healthcare provider, especially if they are planning to travel.

More California News:

Get more local news delivered straight to your inbox. Sign up for free Patch newsletters and alerts.

More from Across California