Mississippi hasn’t had a case of measles since 1992. West Virginia last saw measles – a highly contagious virus that kills an estimated 314 people worldwide every day – in 2009. Now, with California’s new vaccination law rolling out shot by shot, the state joins Mississippi and West Virginia to become the third in the nation to adopt stringent vaccination school entrance requirements. And medical experts say disease rates are likely to fall in California as they have in those states.
“It’s a good club to be in,” said Rahul Gupta, state health officer in West Virginia, who was effusive in welcoming California – home to more than eight times the number of children under the age of 18 as Mississippi and West Virginia combined – as a public health leader in school vaccinations, a role that the two Southern states have played for decades. “What we are seeing in West Virginia is a significant decline in vaccine-preventable diseases,” he said. “We expect the same in California.”
“We haven’t had a measles case in a schoolchild in decades,” said Thomas Dobbs, state epidemiologist in Mississippi, which has the highest school vaccination rate in the nation for measles, mumps and rubella with 99.7 percent of students receiving the immunization.
More than a year after a measles outbreak at Disneyland and Disney California Adventure spread to 134 Californians, as well as to residents in six other states and two other countries, the new law removes the personal belief exemptions that allowed parents not to vaccinate their children in public or private schools or child care centers based on an opposition to vaccines. As in Mississippi and West Virginia, California now allows only children who have a medical reason to be excused from the mandate if they wish to attend public or private schools and child care centers. Child by child, the new vaccination requirements, which took effect July 1, are being applied to babies, toddlers and students entering public or private child care, kindergarten and 7th grade.
Passing the law, known by its legislative number as Senate Bill 277, was arduous at times, as vaccination opponents traveled to Sacramento legislative hearings to voice their belief in a retracted 1998 case study that suggested a link between vaccinations and autism – a case study that the British Medical Journal declared to be “an elaborate fraud.” Public health advocates now are having a moment.
“Policies need to be based on science, not unfounded conjecture,” Dobbs said. “I am very impressed with California.”
California has more than 9 million children under the age of 18, compared with 737,000 children in Mississippi and 382,000 children in West Virginia, according to 2015 figures, making the impact of improved vaccination rates all that more significant.
“Nobody – myself included – was very confident that we could accomplish this law,” said Mark Sawyer, a member of the American Academy of Pediatrics Committee on Infectious Diseases and a medical school professor at UC San Diego. “Now people can see that it can be done – the legislators weighed the risks. I think other states will follow.”
“The likelihood is very strong that the end result will be fewer cases of vaccine-preventable diseases in California,” said Arthur Reingold, professor of epidemiology at the UC Berkeley School of Public Health. Several studies have documented that the easier it is for parents to decline to immunize their children, the higher the opt-out rates are and the greater the risk of outbreaks of measles and pertussis, also known as whooping cough.
In the absence of a federal law requiring school children to be immunized, state governments set the standards. Every state allows children to be exempt from vaccinations if they have a medical reason, such as a compromised immune system or a severe allergy. But 47 states allow parents to choose not to vaccinate their children because of a personal or religious opposition to vaccination. A parent’s right not to vaccinate a child based on beliefs has been defeated several times in Supreme Court rulings that state there is a greater public good in widespread immunization.
West Virginia instituted its vaccination requirements in 1987, has been strengthening them ever since and has never had a religious or personal belief exemption. Mississippi set its vaccination requirements in 1972, never had a personal belief exemption and ended its religious exemption in 1979, when the state Supreme Court ruled against such exemptions.
But in the ensuing decades, the fraudulent paper on the possible link between vaccinations and autism by Andrew Wakefield, a British doctor who was stripped of his medical license by a government review board, has sowed fear in parents and wreaked havoc on vaccination rates in Europe and, to a lesser extent, in the U.S. Both Gupta and Dobbs noted that it is far easier never to have had exemptions to vaccination requirements, or to have removed them decades ago, than to remove them in 2015 as California did.
West Virginia legislators continue to strengthen vaccination laws and in 2015 extended vaccination requirements to preschoolers. Amid complaints from a few parents that medical exemptions were being granted or denied without consistency, legislators last year created the position of state immunization officer, who is in charge of ruling whether a medical exemption is warranted. Having the state immunization officer has reduced complaints to legislators, Gupta said, “and significantly reduced criticism” of the vaccination requirements.
In California and elsewhere, non-medical exemptions have created pockets of unvaccinated children that have facilitated the spread of potentially life-threatening diseases, particularly measles and pertussis, according to a 2016 research review published in the Journal of the American Medical Association in 2016.
The most at-risk groups for the diseases are infants who are too young to be vaccinated and individuals with compromised immune systems, Sawyer said. On July 15, a previously healthy 5-month-old San Diego infant died of pertussis, according to the San Diego County Health and Human Services Agency. On the same day, a 51-year-old San Diego man said to have underlying health issues died of complications from chicken pox, the health agency said.