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The number of people suffering from measles in the US this year has already surpassed the record breaking number for all of 2025.
The US Centers for Disease Control and Prevention has recorded 2,318 cases of measles as of Thursday, according to the agency’s update on Friday.
The US had 2,289 cases in 2025, the worst year for measles in more than three decades. Now, with five months to go, 2026 has become the worst measles year since 1991 — with major outbreaks in South Carolina, Utah and Arizona sickening hundreds and small clusters of cases breaking out in other states.
In Canada, 1,102 cases of measles have been reported so far this year, according to the latest Health Canada update. Most are children. By 2025, because of the outbreak that cost Canada its measles-eradication status, 5,462 cases were reported.
In November, international health officials will meet to decide whether the US and Mexico have them they lost measles. The US eliminated a local measles outbreak in 2000 by maintaining high vaccination rates, which have declined in recent years. less than 95 percent of the input necessary to prevent outbreaks.
The Manitoba government is inviting residents in the Southern Health region to participate in a town hall call about measles. The province has the highest measles population in Canada.
Cases are counted less
While measles cases in the US are on the rise, it may be impossible to tell how far the spread has gone. Public health departments and epidemiologists have long acknowledged that official statistics are incomplete, because some people get sick and don’t seek treatment — something that’s not limited to measles.
In addition, experts say the prevalence may be greater than known because the virus is one of the most common pathogens in medicine and vaccination rates have dropped across the country. National measles, mumps and rubella vaccination rates — which fell to 92.5 percent among preschoolers in the 2024-25 school year, from 95.2 percent in the 2019-20 school year — mask even lower rates in some communities.
In Utah, where public health officials have been battling measles for more than a year, the virus has sickened more than 700 people in that time, according to the state health department. Experts relying on genetics and genetic analysis indicate that a major outbreak along the Utah-Arizona border could be three or four times larger than currently known, said epidemiologist Dr. Leisha Nolen.
Pictured is mud in South Carolina, which has seen the state’s largest outbreak in 35 years. There, the total of 997 may be lower, the state health department said, but you don’t know by how much.
Dr. Brannon Traxler, acting director of the state health department, said the minimum number is “impossible to know and can vary during an outbreak.”
Data gaps can make it difficult to reliably estimate the true extent of the outbreak. Experts say hospitalization rates can be a good measure, but measles hospitalizations are not required to be reported in every state.
“If we had some kind of hard-gold standard of percentage of all cases hospitalized or some measure of severity, that would be another way to measure the size of an outbreak that we could see if it’s consistent with these other measures,” said Damon Toth, a statistician at the University of Utah’s school of medicine who is working on one of the outbreaks in Utah.
‘Innocent spectators’
Dr. Mark Roberts, retired director of the Public Health Dynamics Lab at the University of Pittsburgh School of Public Health, worries more about what he calls “innocent bystanders.”
His team’s measles research and simulations show those who cannot be vaccinated — young children, people with weakened immune systems and those who rarely get strong immunity from the vaccine — bear the brunt of the outbreak early.
Some people see skipping vaccinations as deciding not to wear a seat belt, Roberts said.
“Not vaccinating your child is like saying, ‘I don’t want my car to have brakes,'” she said. “Because you can hit other people. You are not alone in your car. Some people.”
CBC News analysis shows childhood immunization rates appear to be falling in BC The trend comes as a measles outbreak sweeps through northern BC CBC’s Jon Hernandez takes a closer look at the numbers.
