The U.S. reported a slight uptick in measles cases this week, suggesting a deceleration in outbreaks, although instances of exposure at a bustling Colorado airport and a Shakira concert in New Jersey continue to pose challenges for public health officials.

The Centers for Disease Control and Prevention announced on Friday a total of 1,046 confirmed measles cases, reflecting a rise of 22 cases from the previous week. In Texas, where the nation’s most significant outbreak took place during late winter and spring, there were only 10 additional cases recorded this past week, bringing the total to 728.

Elsewhere in North America, there are three primary outbreaks. In Ontario, Canada, from mid-October through May 20, 1,795 cases have been documented, marking an increase of 173 cases within a week. Alberta, Canada, has recorded 538 cases as of Thursday. Additionally, in the Mexican state of Chihuahua, health ministry data indicated 1,578 measles cases and three deaths as of Friday.

Since the outbreak in the southwest U.S. began, two elementary school-aged children in the epicenter in West Texas and an adult in New Mexico have died of measles. All were unvaccinated.

But that outbreak, which affects Texas, New Mexico and Oklahoma, appeared to be “leveling off” last week, U.S. Centers for Disease Control and Prevention incident manager Dr. Manisha Patel said on May 15. But she noted that it’s still “travel season” and there is “a lot of global measles activity right now.”

Other states with active outbreaks — which the CDC defines as three or more related cases — include Kansas, Michigan, Montana, North Dakota, Ohio, Pennsylvania and Tennessee. Indiana’s outbreak was declared over this week.

Measles is caused by a highly contagious virus that’s airborne and spreads easily when an infected person breathes, sneezes or coughs. It is preventable through vaccines, and has been considered eliminated from the U.S. since 2000. Here’s what else you need to know about measles in the U.S.

How many measles cases are there in Texas?

There are a total of 728 cases across 34 counties, most of them in West Texas, state health officials said Friday.

One more person was hospitalized, for 94 total throughout the outbreak.

State health officials estimated less than 1% of cases — fewer than 10 — are actively infectious. Fifty-six percent of Texas’ cases are in Gaines County, population 22,892, where the virus started spreading in a close-knit, undervaccinated Mennonite community. The county has had 408 cases since late January — just over 1.7% of the county’s residents.

The April 3 death in Texas was an 8-year-old child, according to Health Secretary Robert F. Kennedy Jr. Local health officials said the child did not have underlying health conditions and died of “what the child’s doctor described as measles pulmonary failure.” A unvaccinated child with no underlying conditions died of measles in Texas in late February; Kennedy said the child was 6.

How many measles cases are there in New Mexico?

New Mexico added five new measles cases since May 15 for a total of 78.

Seven people have been hospitalized since the outbreak started. Most of the state’s cases are in Lea County. Sandoval County near Albuquerque has six cases, Eddy County has three, Doña Ana County has two and Chaves and Curry counties have one each.

An unvaccinated adult died of measles-related illness March 6. The person did not seek medical care.

How many cases are there in Oklahoma?

Oklahoma held steady Friday with a total of 14 confirmed and three probable cases.

The state health department is not releasing which counties have cases.

How many cases are there in Kansas?

Kansas has a total of 58 cases across 10 counties in the southwestern part of the state, with two hospitalizations. All but two of the cases are connected, and most of the cases are in Gray County.

How many cases are there in Indiana?

All of Indiana’s cases — eight — were in Allen County in the northeast part of the state. The county health department said the cases had no known link to other outbreaks, and there’ve been no new ones since April 21, leading officials declare the outbreak over.

How many cases are there in Michigan?

Michigan has eight confirmed cases of measles, with an outbreak of four connected cases in Montcalm County in the western part of the state that health officials say is tied to the Ontario outbreak.

How many cases are there in Montana?

Montana has 10 measles cases as of Thursday. The state’s only outbreak started in mid-April in southwestern Gallatin County — Montana’s first measles cases in 35 years.

Flathead and Hill counties also have one case each.

Health officials said there is no known local spread of measles, but did note the outbreaks in neighboring North Dakota and the Canadian provinces of Alberta, British Columbia and Saskatchewan.

How many cases are there in North Dakota?

North Dakota, which hadn’t seen measles since 2011, is up to 19 cases as of Friday. One person has been hospitalized.

There are six cases in Cass County on the eastern side of the state. The rest are in Williams County in western North Dakota on the Montana border and are not linked to Cass County.

The state health department said four people diagnosed with measles attended classes while infectious at a Williston elementary school, middle school and high school.

How many cases are there in Ohio?

Ohio remained steady Thursday at 34 measles cases and one hospitalization, according to the Ohio Department of Health. That count includes only Ohio residents.

The state has two outbreaks: Ashtabula County near Cleveland has 16 cases, and Knox County in east-central Ohio has 20 — 14 among Ohio residents and the rest among visitors.

Allen, Cuyahoga, Holmes and Defiance counties have one case each.

How many cases are there in Pennsylvania?

Pennsylvania has 15 cases overall in 2025 as of May 16, including international travel-related cases in Montgomery County and one in Philadelphia.

The outbreak of eight measles cases in Erie County in far northwest Pennsylvania has remained steady since it began in mid-April.

How many cases are there in Tennessee?

Tennessee had six measles cases as of early May. Health department spokesman Bill Christian said all cases are the middle part of the state, and that “at least three of these cases are linked to each other” but declined to specify further. The state also did not say whether the cases were linked to other outbreaks or when Tennessee’s outbreak started.

Where else is measles showing up in the U.S.?

Measles cases also have been reported in Alaska, Arkansas, California, Colorado, Florida, Georgia, Hawaii, Illinois, Iowa, Kentucky, Louisiana, Maryland, Minnesota, Missouri, New Jersey, New York, Rhode Island, Vermont, Virginia and Washington.

Cases and outbreaks in the U.S. are frequently traced to someone who caught the disease abroad. The CDC says more than twice as many measles have come from outside of the U.S. compared to May of last year, and most of those are in unvaccinated Americans returning home. In 2019, the U.S. saw 1,274 cases and almost lost its status of having eliminated measles.

What do you need to know about the MMR vaccine?

The best way to avoid measles is to get the measles, mumps and rubella vaccine. The first shot is recommended for children between 12 and 15 months old and the second between 4 and 6 years old.

Getting another MMR shot as an adult is harmless if there are concerns about waning immunity, the CDC says. People who have documentation of receiving a live measles vaccine in the 1960s don’t need to be revaccinated, but people who were immunized before 1968 with an ineffective vaccine made from “killed” virus should be revaccinated with at least one dose, the agency said.

People who have documentation that they had measles are immune, and those born before 1957 generally don’t need the shots because so many children got measles back then that they have “presumptive immunity.”

Measles has a harder time spreading through communities with high vaccination rates — above 95% — due to “herd immunity.” But childhood vaccination rates have declined nationwide since the pandemic and more parents are claiming religious or personal conscience waivers to exempt their kids from required shots.

What are the symptoms of measles?

Measles first infects the respiratory tract, then spreads throughout the body, causing a high fever, runny nose, cough, red, watery eyes and a rash.

The rash generally appears three to five days after the first symptoms, beginning as flat red spots on the face and then spreading downward to the neck, trunk, arms, legs and feet. When the rash appears, the fever may spike over 104 degrees Fahrenheit, according to the CDC.

Most kids will recover from measles, but infection can lead to dangerous complications such as pneumonia, blindness, brain swelling and death.

How can you treat measles?

There’s no specific treatment for measles, so doctors generally try to alleviate symptoms, prevent complications and keep patients comfortable.

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