Photo: Baylor College Of Medicine
Four Texas cities, including Houston, rank among the 15 metropolitan “hotspots” of vaccine exemptions, more than any other state, according to a new study.
The study found Austin, Fort Worth and Plano also are among the nation’s cities with the highest number of kindergartners not getting vaccinated for non-medical reasons. Since 2009, the proportion of children opting out of such recommended vaccines increased in Texas and 11 other states, the study showed.
“There are some scary trends we were able to identify,” said Dr. Peter Hotez, a Houston vaccine scientist and one of the study authors. “They’re a sign that anti-vaccine groups, such as Texans for Vaccine Choice, have been very successful at lobbying efforts – both of the Texas legislature and through social media and other advocacy — to convince parents not to vaccinate their kids.”
The anti-vaxxer movement claims that vaccines are dangerous to developing bodies. In particular, many believe that trace amounts of mercury in vaccines causes autism.
Public health officials emphasize vaccines are safe and that the theory they cause autism has been discredited. They credit vaccines with bringing seven major infectious conditions under some degree of control – smallpox, tetanus, diphtheria, yellow fever, whooping cough, polio and measles – and saving an estimated 9 million lives worldwide each year.
Hotez said the study, published Tuesday in the journal PLOS Medicine, should be a wake-up call for Texas and the 17 other states that allow non-medical exemptions for personal beliefs to change their laws. He cited a 2015 measles outbreak in California and one in 2017 in Minnesota as examples of the consequences of declining coverage.
The overall number of people invoking non-medical exemptions isn’t yet high enough to threaten herd immunity, the idea that vaccination of most of the population provides protection for those individuals without immunity to a contagious disease. But public health officials fear clusters of “anti-vaxxers” could leave some children vulnerable.
Texas’ increasing exemptions have been well documented. Though the number is still small, they have spiked from less than 3,000 in 2003 to more than 45,000 of the state’s roughly 5.5 million schoolchildren today, a 19-fold increase.
Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine and Texas Children’s Hospital said he undertook the study because of the Texas increase. He said wanted to look at whether it was a phenomenon unique to the state or mirrored elsewhere. National vaccination rates haven’t changed much in recent years.
The list of metropolitan hotspots is dominated by cities in the West. In addition to the four Texas cities, it includes Seattle and Spokane in Washington; Salt Lake City and Provo in Utah; Portland and Phoenix. Detroit, Troy and Warren in Michigan and Kansas City represent the Midwest. Pittsburgh is the only East Coast city on the list.
The study also includes a ranking of the 10 rural counties with the most non-medical vaccine exemptions. Eight are in Idaho. The other two are in Wisconsin and Utah.
Todd Ackerman writes about medicine for the Houston Chronicle. He can be reached at email@example.com or on Twitter@ChronMed.