05-03-2025
Low vaccination rates a warning sign for measles in Arizona
Arizona hasn't had a reported measles case so far this year, but red flags are leading some experts to worry we could see an outbreak like the one in Texas.
Why it matters: Some Arizona counties have lower measles vaccination rates than in west Texas, where the outbreak has infected at least 159 people since it was first reported in early February and has killed one child.
What they're saying: There are "places here where it could spin out of control, just like it has in Texas. The conditions are right here for that to happen in some parts of the state," Arizona Public Health Association executive director Will Humble told Axios.
State of play: A vaccination rate above 95% is needed to prevent measles from spreading, according to the National Institutes of Health.
Four Arizona counties had lower kindergarten immunization rates for the 2023-24 school year than Gaines County, Texas, the epicenter of the Texas outbreak.
Gaines County's vaccination rate is 82%, which is higher than Gila (79.9), Mohave (76), Navajo (79.7) and Yavapai (75.2) counties, per the Arizona Department of Health Services (ADHS).
Statewide, the U.S. Centers for Disease Control and Prevention reported that 89.3% of kindergartners last school year had received two doses of the measles, mumps and rubella (MMR) vaccine, lower than the national rate of 92.7%.
Zoom in: Measles is highly contagious, and "all it takes is a spark," Humble said.
Outbreaks are often driven by tight-knit pockets of unvaccinated people, Megan Jehn, an epidemiologist and professor at ASU's School of Human Evolution and Social Change, told Axios.
The Arizona Republic reported last year that Arizona has seen an increase in students skipping the measles vaccine under the state's "personal belief" exemption.
Between the lines: The MMR vaccine is about 97% effective against measles, Jehn said.
Humble emphasized you can be vaccinated and still get measles if you go somewhere where the disease is rampant.
Yes, but: Even when Arizona sees measles infections, they're generally isolated cases and not part of an outbreak, said Dr. Joel Terriquez, medical director at ADHS.
Arizona had five cases last year, all unrelated, he said.
Most of the cases Arizona sees are "travel cases," Humble said, and there isn't a lot of traffic between here and the Lubbock, Texas area, where the outbreak is centered.
Threat level: Though measles is a minor illness for most, it can pose a risk for serious complications or even death, especially for children under 5.
That includes acute encephalitis, which is brain inflammation that can lead to permanent brain damage. Other potential complications include blindness, ear infections, diarrhea and pneumonia.
An estimated one to three children out of 1,000 who become infected with measles will die, according to the CDC.
Zoom out: Measles cases have also been reported this year in an area of New Mexico near the Texas outbreak epicenter, as well as in Alaska, California, Georgia, Kentucky, New Jersey, New York, Pennsylvania and Rhode Island.
The bottom line: The best way to protect yourself against measles is vaccination, the CDC says.
There is no specific treatment other than managing symptoms and preventing complications.
