A wave of measles cases continues to sweep across the US, with new infections and potential exposures reported in at least a dozen states over the past week.
Health officials from California to New Jersey are urging unvaccinated people to monitor themselves for symptoms and, in some cases, to quarantine after possible recent exposure to the highly contagious virus in nearly a dozen states.
As of March 26, 1,575 cases of measles have been reported in the US since the start of the year across 32 states — already the second-highest annual total since measles was declared eliminated in the US in 2000.Â
In California, Shasta County confirmed a new measles case, bringing the state’s total to at least 32, in a vaccinated individual under 18. The patient is past their infectious period and considered a breakthrough case — an uncommon occurrence given that two doses of the MMR vaccine are more than 97 percent effective at preventing measles.
South Carolina’s record-breaking outbreak, centered in Spartanburg County, now stands at 997 cases since October 2025. But the state has gone a full week without a new infection for the first time since the outbreak began. If no new cases emerge by April 26, the outbreak will be declared over.Â
Dr Linda Bell, South Carolina’s state epidemiologist, said wastewater testing and emergency department surveillance show no signs of ongoing transmission: ‘We don’t see indications there are large numbers of unrecognized measles cases because people are self-isolating.’
The Midwest has also seen significant activity. Michigan confirmed a seventh case in Washtenaw County, all involving unvaccinated individuals.Â
Utah reported 43 new cases in the past week, bringing its total since June 2025 to 486, with exposures at schools, churches, restaurants and even a temple open house.Â
As of March 26, 1,575 measles cases have been reported across 32 states since the beginning of the year — already the second-highest annual total since the disease was declared eliminated in the US in 2000 (stock)
Measles is one of the most contagious viruses known to medicine.Â
Many dismiss it as a childhood rash, but it can lead to severe complications, including pneumonia, permanent hearing loss and encephalitis — a dangerous swelling of the brain that can cause seizures, brain damage or death.
Across the country, health officials are urging unvaccinated individuals to get the MMR vaccine and advising anyone who may have been exposed to monitor for symptoms including fever, cough, runny nose and rash for up to 21 days.
Texas has seen 147 cases concentrated in detention facilities in Hudspeth and El Paso counties, with several infections spreading to the public through facility employees who visited high-traffic areas before diagnosis.
Another 23 cases have been reported in El Paso County, including 17 involving people in custody and six among the public.
In the West, Washington state health officials are warning of widespread potential exposure after a Spokane County adult in their 30s with measles visited nine public locations over an eight-day period earlier this month, potentially exposing hundreds of people.
The locations included Walmart stores, Outback Steakhouse, Frank’s Diner, Five Guys and Chili’s, among others.
The case is not linked to a previous measles case reported in Spokane last week involving an unvaccinated child who traveled from Kootenai County, Idaho.
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‘This is a little bit more concerning just because of the many, many places where the patient was — restaurants, stores, entertainment places,’ said Dr Francisco Velázquez, Spokane Regional Health District health officer. ‘Places you tend to have lots of people in, and it becomes a little bit more difficult to trace and track everyone.’
Oregon confirmed its first measles case of the year linked to a WinCo Foods store in Gresham, Multnomah County.
Dr Richard Bruno, Multnomah County’s health officer, said the risk to the public is relatively low due to the store’s high ceilings and air turnover rate, as well as the county’s high vaccination coverage — nearly 95 percent of schoolchildren are up to date on their MMR vaccines.
In New Jersey, the measles virus was detected in a wastewater sample taken March 20 at a treatment plant serving Bergen, Passaic, Essex, Hudson and Union counties — home to millions of residents in all.
State health officials said the virus may have originated from a traveler, as the plant also receives waste from Newark Liberty International Airport. A second sample taken three days later tested negative.
No outbreak has been reported in the region, but vaccination rates in New Jersey have declined, with 92.8 percent of kindergarteners fully vaccinated in the 2024-25 school year, down from 96.8 percent a decade ago.
Last month in nearby New York City, officials confirmed its first measles case of 2026 in an unvaccinated infant who had recently traveled internationally, though the location and the baby’s name are being withheld for privacy reasons.
New York City saw 20 measles cases in 2025, a slight uptick from the previous year.
Two doses of the MMR vaccine are 97 percent effective at preventing measles, making it the best line of defense. Experts say communities must maintain at least 95 percent vaccination coverage to achieve herd immunity and halt transmission (stock)Â
Virginia confirmed six cases in the southwest part of the state, though officials say no public exposure sites were identified.
Florida has reported 140 measles cases this year, with seven of those being confirmed in the first few weeks of March.
The 15 to 19 age group saw the most reported infections with 59 cases, followed by 20- to 24-year-olds with 45 cases.
Measles is highly contagious and can remain airborne for up to two hours after an infected person coughs, sneezes, or breathes.
Symptoms typically appear seven to 14 days after exposure but can take up to 21 days to develop. Early signs include high fever, cough, runny nose and red, watery eyes, followed by a rash that begins on the face and spreads downward.
Unvaccinated people who are exposed to the virus may need to quarantine for 21 days.
The MMR vaccine remains the most effective protection against measles. Two doses are 97 percent effective at preventing infection.
Public health experts emphasize that achieving 95 percent vaccination coverage community-wide is necessary to maintain herd immunity and stop the virus from spreading.
