Nat Malkus is a resident scholar and deputy director for Education Policy Studies at the American Enterprise Institute.

As novel coronavirus infection rates surge in most states and the new school year approaches, parents are understandably worried about their children’s health. Yet, even as the coronavirus dominates concerns of parents and school leaders, the dwindling rates of routine childhood vaccinations are quietly becoming another dangerous threat to children’s health.

Falling vaccination rates in D.C. were of great concern for Hanseul Kang, the D.C. state superintendent of education, who spoke with me before D.C. had announced a reopening plan. “We are concerned about the need to prevent other significant vaccine-preventable diseases,” she said, “According to D.C. Health, the rate of pediatric immunization administrations has dropped by 70 percent in the District. Thus, many children are not fully immunized, creating a high risk for an outbreak of a vaccine-preventable infectious disease such as measles among our students. D.C. Health has advised that such an outbreak could be as much or even more of a public health risk for school communities than covid-19 itself.”

The same trends extend to the D.C. suburbs and the rest of the nation. In April, neighboring Fairfax County saw a staggering 83 percent drop in vaccinations among infants to 5-year-olds, a key vaccination group, compared with 2019. According to the Centers for Disease Control and Prevention, a variety of vaccination rates are way down across the country. In April, a national survey of 1,000 pediatricians found that child vaccinations had decreased between 42 percent and 73 percent. The threat is real, especially in areas that already had low vaccination rates. For example, under-vaccination in New York City and the state of Michigan led to measles outbreaks in 2019. Since the coronavirus pandemic began, New York City has seen a 91 percent drop in vaccinations of children older than 2, and Michigan experienced a 66 percent drop in vaccinations for adolescents age 9-18 this spring, easily setting the stage for more disease outbreaks.

The coronavirus originally hampered vaccination access. Early in the pandemic, reduced hours at doctors’ offices and difficulties scheduling visits predictably made it harder to get vaccinations. But by May, many practices were open and offering immunizations, yet shortfalls in vaccinations still remain.

Not only has the unrelenting pandemic driven vaccination rates down, it also limits schools’ traditional role of backstopping vaccination rates. Most schools won’t let kids enter without up-to-date vaccinations, thus ensuring high enough vaccination rates to meet the threshold for herd immunity. Schools also help identify under-vaccinated students and even provide vaccinations to those who need them. Every year, schools function as essential backstops to ensure against the spread of infectious diseases.

But this year, as more and more districts start the year remotely, there is a growing number of students for whom schools won’t play their traditional role backstopping immunizations. Laudably, D.C. Public Schools just announced it would maintain immunization requirements even as it has closed buildings to 47,000 students, but it is unclear how those stipulations will be enforced. Los Angeles United School District will also open remotely for more than 600,000 students, but its only mention of immunizations comes on the 31st of a 43-page plan. Many other districts are going remote without mentioning immunization requirements at all. This includes Houston Independent School District, which serves some 200,000 students, and, in our own backyard, Fairfax, Montgomery and Loudoun counties, whose remote starts cumulatively affect nearly 435,000 students. Given the difficulties in ensuring the virtual participation of students this spring, it’s hard to imagine districts will tell their students that they can’t participate in remote learning in the fall without a vaccination form. This leaves huge numbers of students potentially at risk for preventable infectious diseases.

While closing schools may mitigate the danger from the coronavirus, it doesn’t guarantee that children won’t congregate and risk catching other diseases. When schools are meeting virtually, thousands of parents, many with unvaccinated children, will have to find child care somewhere. As established child-care centers are increasingly strained, parents will look to informal child care or new facilities that lack typical vaccine regulations. Many parents are also opting out of traditional school in favor of small “learning pods,” or micro schools made up of several community families. It is doubtful participating families will have any vaccine regulations. Children will gather even if schools are closed, but because many more of these children will be unvaccinated, there will be increased risk of diseases more dangerous to them than covid-19, the disease caused by the coronavirus.

The mercilessness of this pandemic means public health authorities, who already have their hands full because of the coronavirus, must find a way to raise vaccination rates for unvaccinated children, often without relying on schools and their typical role as a backstop measure. They will need to identify children who may be congregating in unknown, often unregulated child-care arrangements without safeguards for vaccinations. As authorities in New York City and Michigan will attest, failure to do so could pose serious threats to children’s health. If authorities can’t figure out how to solve the problem of falling vaccination rates while schools are closed, we may have more dangerous outbreaks to worry about than just the coronavirus.

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