The Centers for Disease Control and Prevention report also shows continued decline in vaccination rates for three other childhood vaccines that prevent diphtheria, tetanus and pertussis (Tdap), poliomyelitis and chickenpox among kindergartens in 2021.
The latest data highlights fear that growing parental resistance to routine childhood vaccinations is fueling a resurgence in vaccine-preventable diseases, such as the recent measles outbreaks in Minnesota and Columbus, Ohio, which sickened more than 100 children last year. The pandemic has amplified the problem due to politicization around coronavirus vaccines and the lingering impact of school closures and fewer children going to doctors on vaccination rates.
“We know that measles, mumps and rubella vaccination coverage for kindergarten children is the lowest in over a decade…and that’s something to be concerned about,” Georgina said. Peacock, director of CDC immunization services, during a briefing.
While a two percentage point drop in measles vaccination rates may seem insignificant, health officials and experts warn that even the smallest drop allows the virus to spread faster, causing outbreaks in groups of unvaccinated children. Measles is so contagious that people who may not know they are exposed can become infected and pass the virus on to family members or other contacts before they show symptoms.
In addition to being potentially deadly, the measles virus weakens the immune system and makes a child more susceptible to other illnesses such as pneumonia and diarrhea – an effect that lasts for months after the body has eliminated the virus. measles infection.
Sean O’Leary, an infectious disease pediatrician, called recent outbreaks of vaccine-preventable diseases like measles and polio “alarming”. Immunization in childhood is critical because “it equips children’s immune systems to recognize and resist disease so they can grow and live healthy lives into adulthood,” he said. during the briefing.
O’Leary, who cares for hospitalized children, said many of them could be prevented with “the simple and safe step of keeping your child up to date on recommended vaccines”.
Federal data shows nine states and the District of Columbia with vaccination coverage among kindergartners below 90%, including Ohio and Minnesota. It is the highest number of states to fall below that level in data released by the CDC, which dates back to 2009-2010. New York, Nebraska, North Carolina and Tennessee are among 12 states where MMR vaccination rates exceed 95%.
Coverage of kindergarten children for the four childhood vaccines — to prevent measles, diphtheria, tetanus and pertussis (DTaP), poliomyelitis and chickenpox – was about 93% nationwide in the 2021-2022 school year, up from 94% in 2020 -2021 and 95% in 2019-2020.
The decline means more than 275,000 kindergartners may not be completely protected against these diseases, according to the CDC.
Measles is an ‘imminent threat’ worldwide, warn WHO and CDC
Several factors are behind the decline. Pandemic-related health system disruptions have delayed pediatric exams. Partly because of this, suppliers have ordered fewer doses from the federal program that provides vaccines to half of all American children. In some cases, schools also lack staff to ensure parents submit medical documents on time.
And concerns about the value of the coronavirus vaccine increasingly spills over into routine vaccinations.
“We have seen some hesitation in vaccines during the pandemic related mainly, I think, to the covid vaccine. And that could, in some cases, translate into routine vaccinations,” the CDC’s Peacock said. “And that’s something we’re watching very closely.”
Preventable diseases have spread rapidly, she warned, pointing to recent measles outbreaks in Ohio and Minnesota.
The CDC recommends children get two doses of the MMR vaccine, the first dose between 12 and 15 months and the second between 4 and 6 years old. One dose of vaccine is about 93% effective in preventing measles; two doses are approximately 97% effective.
In the Columbus outbreak, most of the 83 infected children were old enough to get vaccinated, but their parents chose not to, officials said, leading to the largest outbreak of the agent. highly infectious pathogen in the country in 2022. If no new cases are reported by Jan. 30, authorities will likely declare this outbreak over, said Myles Bell, a spokesperson for the Columbus Health Department.
Minnesota reported 22 measles cases between June and November last year, but they occurred in multiple clusters. This trend was more concerning than a single large epidemic, such as the the one the state experienced in 2017.
The clusters “remained contained like small campfires, but each had the potential to grow significantly into a wildfire that could have had more severe consequences,” said Doug Schultz, spokesperson for the health department. of Minnesota. Vaccine hesitancy was a contributing factor to both outbreaks, health officials said.
Peacock and O’Leary also highlighted the case of paralytic polio in a New York man this summer that has raised concerns about low childhood immunization rates and growing misinformation about vaccines could lead to the resurgence of the disease, decades after vaccination eliminated it in the United States.
“I think all of this proves that we have pockets in the United States where we have low vaccination coverage in children … and also in these particular communities a need to increase vaccination rates,” Peacock said in an interview. .
The CDC launched an initiative this week to restore routine immunizations for adults and children on schedule. Authorities are giving health care providers more information and strategies to help them talk about vaccines and work more intensively with community groups in areas where vaccination rates are very low.
Rupali Limaye, an associate professor at Johns Hopkins University who has studied vaccine hesitancy, said the overall drop in childhood vaccination rates is concerning, and the drop in measles vaccination in particular is dangerously small. and “quite concerning”.
Over the past three years, she has spoken to hundreds of parents, churches and other community groups about the coronavirus vaccine. Many people may not have had problems with the routine vaccination schedule before the pandemic, she said. But confusing messages about the need for children to get vaccinated against the coronavirus “affected their decision-making about these routine vaccinations”, Limaye said.
Vaccination advocates say it’s hard to increase vaccination rates without better understanding why they’ve fallen.
“The most recent surveys show that parents are still overwhelmingly supportive of childhood vaccines, so is it an awareness issue?” asked Erica DeWald, director of strategic communications at Vaccinate Your Family, a vaccination advocacy group. “Or do we identify the access issues that have arisen as a result of the pandemic? We must continue to work with community partners to identify and remove underlying barriers to immunization. »
Dan Keating contributed to this report.