(Bloomberg) — Measles could once again become native in the U.S., disease experts worry, as an outbreak in California linked to Disneyland has put a spotlight on a growing failure to vaccinate that's helping the disease to spread.
While 94 percent of California kindergarteners were fully inoculated against the virus last school year, according to the U.S. Centers for Disease Control and Prevention (CDC), there are clusters where vaccination is much lower. In some pockets of California, as much as a quarter of children are undervaccinated — putting them at risk of both contracting the disease and becoming a nexus of future spread.
"Children die as a result of this disease," said Greg Poland, professor of medicine and infectious diseases at the Mayo Clinic in Rochester, Minnesota, and director of the Mayo Vaccine Research Group. "In 1990, 3 of every 1,000 children who got measles died from it. That wasn't the dark ages. We don't have an effective treatment for measles. The only thing we have is prevention."
Coverage for measles vaccinations is part of the Patient Protection and Affordable Care Act (PPACA) basic preventive services package. All people with non-grandfathered major medical coverage are supposed to be able to get measles vaccinations without having to pay a co-payment, a deductible or other cost-sharing amounts.
The measles virus is one of the most contagious pathogens known to man, and causes more serious complications in about three of 10 patients, according to the CDC. It was declared eliminated in the U.S. in 2000, and outbreaks are instead started by people visiting from outside the U.S. or who return and bring it back.
Re-establishing transmission would mean there is sustained chain of infection among U.S. citizens and the disease can no longer be considered eliminated. The CDC warned in 2012 that without high vaccination rates, measles could return.
'Biggest fear'
"What's sad is seeing a disease that is so preventable causing all these problems," said Walter Orenstein, associate director of the Emory Vaccine Center at Emory University in Atlanta. "My biggest fear is we will re-establish transmission and have many more cases."
Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases, said measles re-establishing itself is less likely than the U.S. developing more frequent outbreaks from imported cases.
"You have parents who don't allow their children to be vaccinated, and they're clustered in certain areas," Fauci said in an interview. The parents reinforce their philosophy of not wanting to get the kids vaccinated. So you have a cadre of kids who aren't vaccinated and someone comes in from a foreign country that does have endemic measles, and you get outbreaks.''
See also: PPACA: Use of Preventive Care May Grow.
Fourteen years after the U.K. declared measles eliminated, it once again became endemic in 2008 after a decade of low measles, mumps and rubella vaccination rates, according to the scientific journal Eurosurveillance.
Vulnerable pockets