Vaccination rates for kindergarten students are falling. Here’s why doctors say that’s 'really bad news.'

Childhood vaccination rates have fallen for the third year in a row, according to a new report from the Centers for Disease Control and Prevention (CDC). The report found that 93% of kindergartners received state-required vaccines during the 2021-2022 school year, a drop of two percentage points from the 2019-2020 school year. During the 2020-2021 school year, 94% of kindergarteners received their required vaccinations, showing a gradual downward trend in routine childhood vaccinations.

Overall, 2.6% of children had an exemption for vaccines last year, and vaccination coverage for the measles, mumps and rubella (MMR) vaccine is the lowest it has been in a decade. Coverage with the diptheria, tetanus and acellular pertussis (DTaP), polio and varicella vaccines also fell in most states.

"It's so discouraging," Dr. Danelle Fisher, chair of pediatrics at California's Providence Saint John's Health Center, tells Yahoo Life. "We've come a long way with childhood vaccinations, and now people have a fear about vaccines that's getting reawakened."

Dr. Juan Salazar, physician in chief at Connecticut Children’s, tells Yahoo Life that this is "really bad news" and "very concerning."

There's a lot to unpack around this drop in childhood vaccinations. Here's what you need to know.

What is behind the decline in vaccines?

Experts say there are a few potential factors at play. "During the first year of the pandemic, well child care visits dropped dramatically, starting this downward trend in immunization rates," Dr. Michael Bauer, a pediatrician and medical director at Northwestern Medicine Lake Forest Hospital, tells Yahoo Life.

At the same time, the pandemic became politicized and encouraged "a simultaneous rise in public health policies coming into question and distrust in government decisions — leading to an increase in anti-vaccination sentiment," Bauer says.

"That anti-vaccination noise has deterred parents from not only avoiding COVID vaccinations, but other vaccines as well," Dr. Thomas Russo, chief of infectious diseases at the University at Buffalo in New York, tells Yahoo Life. Fisher agrees. "Misinformation about the COVID vaccine has started this distrust of vaccines in general," she says, adding that these routine childhood immunizations are "tried and true vaccines" that have been used for decades. "It's very sad that a segment of the population is buying into this misinformation and not getting their children protected," Fisher says.

Along with the distrust, Bauer notes "an increase in the number of states enacting laws allowing parents to refuse to vaccinate their children aside from medical reasons." He adds that "states that have the strictest laws have the highest rates of vaccine compliance."

What are the health implications of even a slight drop in vaccine rates?

Both the unvaccinated children and those around them can be at risk for getting sick, Salazar says. He cites the recent measles outbreak in Ohio — which largely impacted unvaccinated children — as an example of what can happen when vaccination rates start to decline.

"Even a slight drop in vaccination rates can lead to dramatic increases in these preventable illnesses, as evidenced by recent outbreaks of measles, which is highly preventable," Bauer says.

"We know these vaccines work," Salazar says. "You introduce one of these very transmissible viruses to a school or day care and it will spread." Of particular concern, Salazar says, are the youngest children in day cares or little siblings of older children who are too young to be partially or fully vaccinated against certain diseases such as measles, which is very contagious. "These young children can potentially get very sick and die," he says. "Your bad or uninformed choice is going to affect a child whose family was doing everything right but who was not vaccinated yet because of age."

What happens if these vaccination rates keep dropping?

Childhood vaccination rates have been on a steady decline for years, and doctors say that's concerning. "If this trend continues, we'll have a lot of comeback of certain diseases like measles and perhaps even polio," Russo says. "We will see comebacks of pediatric infections that were virtually nonexistent prior to this. If someone brings in an infection, it will take off."

Salazar says he's concerned that "we're going to get back to a time where measles caused outbreaks and death." He says he's also worried that "Chickenpox will come back with complications," noting that "We have to get back to understanding what it means to have pertussis, measles and complicated varicella. People have forgotten, and it's bad."

Fisher urges parents to vaccinate their children on time. "It's no joke," she says. "Your child's life depends on it."

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