(Bloomberg) -- Vaccines have done more than any other medical innovation to save lives and improve health. Yet the persistent and incorrect belief by a minority of parents that immunizations are more dangerous than beneficial is undermining those advances. The anti-vaccine movement that first took hold in the U.S. and parts of Europe is now spreading globally, with the World Health Organization including “vaccine hesitancy” in its Top 10 list of health threats for 2019. At a time when 3 million people worldwide die of infections that could be averted by vaccines each year, public-health officials worry that eradication efforts are losing ground.
Vaccine-preventable diseases are making a comeback in the U.S. and Europe, while efforts to slow them in poorer countries have stalled. Although vaccination eliminated measles from the U.S. in 2000, international travelers have brought the virus back each year since and sparked outbreaks among the unprotected. The situation is worse in Europe, where more than 82,000 people contracted the disease in 2018 and 72 died. Measles is on the rise throughout the world, with outbreaks reported in every region. The number of deaths rose to 110,000 globally in 2017, up from less than 90,000 a year earlier. And it’s not just measles. Whooping cough, which can be lethal for babies, has remained at elevated levels since 2012, when it killed 20 people in the U.S. and 10 in the U.K. The number of children going unprotected from a variety of contagious illnesses has grown amid grassroots campaigns to convince parents incorrectly that immunizations often trigger side effects such as autism, a developmental disorder associated with difficulties in speech or social interactions. Fears that infants’ immune systems may be overwhelmed by multiple immunizations given at once has led some parents to space them out, though studies show they are safe when given simultaneously. The result is delayed protection and in some cases vulnerability when doses are missed entirely. Communities where anti-vaccine sentiment spreads can lose herd immunity, which occurs when so many people are protected a pathogen can’t take hold and dies out. That protection is essential for those who can’t get vaccinated, such as very young infants and people with certain medical conditions. Herd immunity can even benefit those who got vaccinated, since no immunization is perfectly effective.
While opposition to immunizations has been around for as long as the shots, the most recent anti-vaccine movement took off after the medical journal The Lancet published what turned out to be a fraudulent study in 1998 linking the measles, mumps and rubella vaccine to autism. The Lancet retracted the study in 2010 and the U.K.’s General Medical Council stripped its author, Andrew Wakefield, of his medical license for “dishonest” and “irresponsible” work. By then many parents had latched on to the idea that vaccines were to blame for a rise in autism diagnoses. Researchers have concluded that much if not all of the increase in autism prevalence is a result of greater awareness of the disorder and changes in how it’s diagnosed. While a true increase hasn’t been ruled out, repeated studies have debunked any connection to vaccines. The myth of a link expanded in 2005 with claims that the vaccine preservative thimerosal causes autism. Numerous studies have shown that vaccines containing thimerosal are safe.
In the U.S., all 50 states require specific vaccines for students. Medical exemptions are universally granted and 17 states allow unvaccinated students to attend school if their parents hold philosophical objections to immunization. Some public-health specialists support eliminating such waivers. In striking down a religious exemption, Mississippi’s Supreme Court said the state had an “overriding and compelling public interest” in protecting children. Other health advocates argue that making vaccination compulsory would harden the position of refusers. There are historical precedents. In Europe, the strongest anti-vaccination movements tend to be in countries that made vaccines mandatory in past centuries. A number of U.S. states have made vaccine exemptions harder to get. These changes have increased vaccination rates somewhat, probably by motivating parents who’d chosen exemptions out of convenience. Changing the attitudes of true vaccine refusers is much more difficult, research suggests. Australia stopped offering child-care benefits to such parents in 2016. The new rules boosted vaccination rates, with the number of fully immunized one-year-olds and five-year-olds hitting record highs of 94 percent to 95 percent in 2017. Prominent U.S. medical ethicist Arthur Caplan suggests that the parents of unvaccinated children who sicken others, in some cases fatally, should be held legally liable.
The Reference Shelf
- Comedy duo Penn and Teller demonstrate the value of vaccines in this video. And comedian John Oliver called out the anti-vaccine movement in his HBO television show, Last Week Tonight.
- A U.S. Institute of Medicine report provides evidence for actual vaccine side effects.
- This World Health Organization paper documents benefits of vaccination. This one gives the history of immunization.
- The National Conference of State Legislatures maps vaccination exemptions across the U.S.
©2019 Bloomberg L.P.