Even after California banned non-medical exemptions for vaccines, an unvaccinated teenager in the country has still spread measles to half a dozen people during an outbreak last year, reports a new study. The results show that it is essential to tighten legislative loopholes in order to stop the spread of measles.
The epidemic survey, published today in the Center for Disease Control and Prevention Weekly report on morbidity and mortality, follows a 15 year old boy who returned from England in late February 2018 with measles. Shortly after, he infected a second boy at a scouting, a third at school and a fourth at a tutoring center. All were not vaccinated. And the epidemic does not stop there; it continued in a complicated network of contacts.
The third boy, infected at school, was quarantined and was not passed on to anyone. However, public health officials did not learn that the fourth boy, who was infected at the tutoring center, was not vaccinated. He remained un-quarantined and infected his unvaccinated 33-year-old uncle and his unvaccinated 4-year-old brother.
The second boy, who was infected during Scouting, then contaminated a vaccinated virus. 21 year old man at a different Scout event. In this particular chain, measles has stopped in the vaccinated 21 year old. He has contracted a less serious infection called modified measles – when measles infects someone who is not fully protected by a vaccine. It's possible he did not pass the virus on to anyone because people with modified measles tend to lose fewer viruses, according to George Han, chief of health at the county's Department of Public Health. Santa Clara and lead author of the study.
The measles vaccine protects about 97% of people who receive both doses, so it does not protect everyone. People who are not fully immunized and people too young or too sick to get vaccinated depend on everyone. other be vaccinated against the virus. This is why these networks of contagion between unvaccinated people are so disturbing. "We must not let go of a false sense of security: the new vaccine law will completely prevent all outbreaks in California," Han said. "It's a reminder that we should continue to vaccinate – because there are people who can not be vaccinated."
The fight against the return of measles will require a multiple strategy, according to Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine, who did not participate in the study. "He has a political solution, which continues to close the non-medical exemptions," Hotez said. "But that will not be enough in itself." He believes that anti-vaccination propaganda should also be under control and that federal agencies will need to strengthen advocacy for vaccines.
It is not surprising that measles spread so easily from this boy in 2018 – the virus is incredibly infectious. It's also dangerous. In addition to causing a rash and fever, it can cause pneumonia, brain damage and death. Before the measles vaccine, measles hospitalized about 48,000 people and killed between 400 and 500 people in the United States each year, according to the CDC. In 2000, with the widespread use of the safe and effective vaccine against measles, mumps and rubella (or MMR), public health officials announced that the virus had been eliminated in the United States.
But the virus can still affect people from areas where measles is still endemic and spread through pockets of unvaccinated people across the United States, such as in New York, New Jersey, New York, New York, New York, New York, New York, New York, New York, New York, New York. Washington State and Texas. Texas and Washington are among 17 states with legislative loopholes that allow parents to avoid vaccinations of their children because of their personal beliefs, according to the National Conference of State Legislatures. But California is not one of these states: after a Disneyland-related epidemic that sickened 147 people in late 2014 and early 2015, California removed personal belief exemptions for vaccines. This means that only children with medical exemptions by a doctor could enter kindergarten (or, if they were already in school, in seventh grade) without their vaccines after 2016.
After the bill, overall exemptions decreased, but the number of medical exemptions – especially in counties where the rate of exemptions for personal beliefs was high – increased, according to a study published in the Journal of the American Medical Association in 2017. The authors of the study hypothesized that parents reluctant to vaccinate their children might have sought out doctors willing to write medical exemptions, even if it was not possible to do so. there was no medical reason to do it.
This could than what was happening in this California outbreak in 2018, although today's study authors do not speak directly to say so. Do you remember the fourth boy – the one who was infected at the tutoring center and then infected his family? It turns out that this boy and his four-year-old brother had both received a medical exemption for all vaccines from a doctor who worked hundreds of miles from home. None of the two boys had major medical reasons to qualify for an exemption, including a cancer treatment or an organ transplant. "We know that the medical exemptions that these two brothers received were identical, which in itself is a bit strange and did not contain these known medical reasons," Han said.
Currently, there is no standardized set of criteria a patient must meet to qualify for a medical exemption in California, Han said. A potential solution is therefore to reinforce these standards. "Regulations could be put in place to better define what constitutes a medical exemption in California," Han said.
Hotez, for his part, is optimistic about the is not a cottage industry of doctors providing medical exemptions for non-medical reasons. But if there are any, "the licensing authority and the state's medical committees are going to have to take tough measures," says Hotez. "Closing non-medical exemptions like California in 2016 was an important first step, but it's not the only step," he says. "There are still things to do."