Herd immunity refers to the idea that the more people in a community who are immunized, whether by vaccination or by natural immunity, the more protected the entire community is.
Babies who can’t be vaccinated yet, those with compromised immune systems and people with medical exemptions from vaccines rely on herd immunity to protect them, Wervey Arnold said.
The percentage of the public that needs to be immune for the safety net to work varies based on the disease, but in general, health officials put it above 90 percent.
Of the more than 2,000 elementary schools in Ohio, 62 percent met that standard for incoming kindergartners by the October deadline.
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That rate has been steady for the three years the Dayton Daily News has obtained school-level data. 60 percent of schools met the herd immunity threshold last school year and 62 percent the year before.
But the law requires an even higher threshold. Every student is supposed to have evidence of all required shots, or have submitted an exemption, by 14 days into the school year or they are not allowed to attend.
In the Cincinnati Public Schools district, half the elementary schools that submitted data reported fewer than 50 percent of their incoming students were fully vaccinated. One school, Kilgour Elementary, had only two of 94 kindergartners up-to-date on all vaccines. No students had exemptions.
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As in past years, the majority of schools are not missing the mark because of parents opting out. Less than 1 percent of incoming kindergartners had medical exemptions and 2 percent asked for religious or reason of conscience exemptions.
The low vaccination rates are due to those students who simply haven’t completed their shots by the deadline, or haven’t turned in paperwork to the school.
Schools say they work throughout the year to get all students up to date, but health officials are concerned that the lack of records could be masking a bigger issue.
“Kids should not be in the school system… they have to have something on file,” Wervey Arnold said. “It’s not acceptable.”
The Ohio Department of Health said about 90 percent of schools turn in their vaccination data. The state has no authority to force schools to turn in the information or to take action if a school reports that not all students are vaccinated per state law, according to ODH spokeswoman Melanie Amato.
“It is up to the school to enforce the law,” she said, unless there is an outbreak. “If there is an outbreak we have the authority to go in and shut down the school or remove the kids that don’t have vaccinations.”
In the event of an outbreak, schools without complete records could be left scrambling to determine which students need to be sent home, Wervey Arnold said.
From 2015-16: Low vaccination rates in schools concern health officials
The Ohio Chapter of the American Academy of Pediatrics helped draft legislation introduced last year that aimed to improve the state’s record keeping. House Bill 564, sponsored by state Rep. Dan Ramos, D-Lorain, didn’t get out of committee last session, but the AAP said they are working with lawmakers to reintroduce something similar.
It would put the responsibility on the state health department to make sure schools comply with state law and would require the state to publish school-level vaccine data for parents to be better informed.
“We’re not taking away any parents right to decide to not vaccinate their child,” Wervey Arnold said. “We just want to make sure all the schools are reporting through the system, which we know they are not, and we want to make sure parents are having a conversation with an actual health care provider before making that decision,” Wervey Arnold said.
The previous bill included a requirement that any parent seeking a non-medical exemption for their child would need to have a conversation with a physician about the decision not vaccinate and then that doctor would sign off on a standardized exemption form.
Wervy Arnold said Michigan implemented a similar law and saw a 36 percent reduction in parents opting out in just one year.
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But parents who advocate for the right not to vaccinate say they are unfairly targeted, when the data shows they aren’t the problem.
“It’s a really really small population that is taking the exemptions,” said Stephanie Stock, spokeswoman for Ohio Advocates for Medical Freedom. The group circulated a petition against House Bill 564 that got more than 2,100 signatures.
Parents who are choosing not to vaccinate are largely concerned with the risk of adverse effects from vaccines, Stock said.
The National Vaccine Injury Compensation Program has paid out more $3.6 billion for vaccine injuries and deaths since 1989, and Stock points out that only a fraction of cases where someone suffers an injury from a vaccine are reported or ever go to court.
She chose not to vaccinate her second child after the first was injured from a vaccine.
“People need to realize, this isn’t just some belief that we have, most of the parents that aren’t vaccinating, are either not vaccinating because they have an injured child already or they have really, really looked into the injury payouts, the types of reactions that occur and they just don’t feel that the benefits outweigh the risks for their child.”
In 2005, the FDA approved a new booster vaccine, for tetanus, diphtheria and pertussis called Tdap. Since then, 46 states have mandated that 11 or 12 year olds receive the booster shot, especially to combat pertussis, or whooping cough.
In a new study by the National Bureau of Economic Research, Vanderbilt researches found that the mandate has lead to fewer whooping cough cases and deaths. Infants are especially susceptible to serious complications from whooping cough, including death.
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Between 2008 and 2013, the authors found a 53 percent decline in pertussis cases nationwide. Rates of death from pertussis fell for all age groups as a result of greater herd immunity, they concluded.
In Ohio there were 961 cases of whooping cough reported last year and 47 outbreaks across the state. So far in 2017 there have been three outbreaks.
Ohio began mandating the Tdap booster for those entering seventh grade in 2014. This school year, three out of four schools with seventh graders reported 90 percent or above compliance with the Tdap shot, but several Cleveland Public Schools reported few or zero seventh graders had records of receiving the shot.
“It’s really about a much larger public health issue,” Wervy Arnold said of low pertussis immunization rates. “We keep having outbreaks of whooping cough and it’s really dangerous for infants.”
How many kids are vaccinated at your child’s school?