The measles outbreak in western Texas now has ballooned to 124 cases, according to data released on Tuesday by the Texas Department of State Health Services. This represents an increase of 66 cases since last Tuesday. Eighty cases have been reported in Gaines County and 21 cases have been reported in Terry County. Additional cases have been reported in Dallam, Dawson, Ector, Lubbock, Lynn, Martin and Yoakum counties. Thirty-nine of the cases have been in children under the age of five, while 62 cases have been in people between the ages of 5 and 17. One hundred nineteen cases have occurred in people who were unvaccinated or their vaccine status was unknown. Public health officials in New Mexico have reported nine cases in that state, all within Lea County. Although Lea County borders Gaines County, it has not yet been shown that the two outbreaks are linked.
This outbreak will continue to spread locally and may spread more broadly. Indeed, public health officials on Monday issued an alert for people in south-central Texas. A person from Gaines County visited Texas State University, UT San Antonio, and several other public locations in San Marcos and San Antonio between February 14 and February 16. That individual subsequently was diagnosed with measles. In the TDSHS alert, officials note that the person was contagious during their trip and may have exposed other individuals to the virus. People who may have been exposed should monitor their conditions, especially if they are unvaccinated.
The measles vaccine, administered as part of the measles mumps rubella vaccine, is very safe and highly effective. Indeed, public health officials announced in 2000 that widespread vaccination ended the sustained transmission of measles in the United States. Only sporadic outbreaks now occur.
However, the vaccine does not provide 100% protection. Studies have shown that it’s about 97% effective, but what does that actually mean? Basically, people who are vaccinated are 97% less likely than people who are unvaccinated to get measles, assuming that people in both groups are exposed similarly. Let’s look at it another way. If 100 people in an unvaccinated group develop measles, then only 3 people in a vaccinated group should develop measles. And vaccinated patients tend to have milder symptoms and are less likely to transmit the virus to others.
Of course, myriad factors, including the underlying health of an individual, a person’s age, or the extent of exposure all can influence the outcome in a specific person. But the general trend holds. This vaccine is incredibly effective.
Still, a risk to vaccinated people does exist. For example, about 5% of the patients in a large outbreak that occurred in 2018 in New York City were vaccinated. And although most cases in Texas have occurred in unvaccinated people, five cases have been reported in vaccinated individuals.
Increasingly, vaccine deniers are using a “personal choice” framework to argue against vaccine requirements. Indeed, when asked about vaccines in 2024, Robert F. Kennedy, Jr., now the secretary of the Department of Health and Human Services, stated that, “people can make individual assessments about whether that product is going to be good for them.” But it’s not simple. One person’s decision to forego a safe and effective vaccine could affect multiple people in tragic ways. Decreasing vaccination rates negatively affect all of us.
