Even a minor drop in the number of children vaccinated against measles can have substantial public health and economic consequences, according to a new study.
The results directly confront the idea that measles is no longer a health threat in the United States and demonstrate what happens when states allow nonmedical personal belief exemptions for childhood vaccinations.
Researchers estimated that even a 5% decline in children ages 2 to 11 receiving the MMR (measles, mumps and rubella) vaccination would result in an estimated threefold increase in national measles cases in those kids, according to the study published in JAMA Pediatrics. The result would have consequences for both public health and costs: A total of 150 cases of measles and an additional $2.1 million in costs.
The size of the outbreaks increased with declining vaccination coverage, according to the results.
The United States saw an outbreak of measles in Minnesota earlier this year, with more cases there than in the entire country last year. The majority of people who got measles were not vaccinated. Hundreds of cases of mumps were also reported across the country since the start of 2017.
The study estimated the number of measles cases in U.S. children and the associated economic costs under different scenarios where vaccines were either delayed or refused because of nonmedical personal beliefs.
Two researchers, Nathan C. Lo, of the Stanford University School of Medicine in California, and Peter J. Hotez, M.D., of the Baylor College of Medicine in Houston, used data from the Centers for Disease Control and Prevention to simulate county-level MMR vaccination coverage. They then used a mathematical model for infectious disease transmission to estimate distribution of an outbreak. They based the economic costs per measles case on published literature.
“The results of our study find substantial public health and economic consequences with even minor reductions in MMR coverage due to vaccine hesitancy and directly confront the notion that measles is no longer a threat in the United States,” the authors wrote.
“Removal of the nonmedical personal belief exemptions for childhood vaccination may mitigate these consequences. These findings should play a key role in any policies adapted by state or national governments that relate to childhood vaccination,” the study concluded.
The election of President Donald Trump had some scientists worried about reports he planned to establish a panel on vaccine safety which could cause some people to refuse protective immunizations, leading to epidemics of highly contagious diseases.
During his campaign, Trump voiced concerns about the safety and timing of vaccines, giving credence to the antivaccine movement. Before taking office, Trump met with vaccine skeptic Robert F. Kennedy Jr., who said he talked to Trump about chairing a committee to study vaccine safety.