Families avoiding immunization appointments for fear of COVID-19 contagion are further undercutting Colorado’s abysmal childhood vaccination rates, state health leaders say, raising the possibility of new outbreaks of previously vanquished illnesses such as measles or diphtheria.

Childhood immunizations in the first two months of the outbreak have dropped nearly 20% from a year ago at Pediatrics West, a large primary care practice with two metro area locations, said Dr. Shen Nagel, a pediatrician and president of the practice. Parents are staying away even though the 12,500-patient practice designated one of its offices for wellness and vaccines and the other for seeing sick patients.

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Even under the extreme social-distancing orders issued by the state, visits to medical providers for vaccines are considered necessary activities.

But parents have said they worry about the providers shuttling between the two offices, as well as going out in general, Nagel said. He believes their 80% success rate recently is likely better than many practices that can’t separate patients or take other measures. For perspective, researchers say about 95% of children need to be vaccinated against measles in order for the whole population to be protected from the disease.

States reporting figures from a federal program for uninsured children show drops of up to 70% from pre-COVID-19 periods.

“We give vaccines because they’re extremely important for both their own children’s health and the health and safety of the pediatric and adult population in general,” said Nagel, whose practice normally spends more than $100,000 a month buying vaccines. “The worst-case scenario in this would be dealing with this crisis and also a measles outbreak or an increase in whooping cough.”

Primary care practices are likely “the safest places to be”

State health officials and pediatrics leaders, who keep a registry of immunizations as well as handle orders for vaccine materials through a federal program, are concerned enough about the drop in rates that they are forming a new task force to promote solutions.

“It is an impending crisis,” said Dr. Sean O’Leary, an associate professor of pediatrics and infectious diseases at the University of Colorado Anschutz Medical Campus and Children’s Hospital Colorado, as well as a vaccination expert on the national board of the American Academy of Pediatrics. O’Leary in his various roles speaks with most practices around the state, and does not like what he hears.

“If we have a large enough group not vaccinated, we will start to see outbreaks,” he said. “Just to give you an idea with measles as an example: At one year of age if a child is not vaccinated they essentially have zero protection against measles because the protection they got from the placenta has worn off. So if they are exposed they will likely get it.” An outbreak concentrated in New York state last year spiked U.S. measles cases past 1,000, at least in part because of low vaccination rates in local religious communities.

Primary care practices that are taking virus-prevention measures are “probably the safest places to be right now,” O’Leary said, with providers wearing protective gear and wiping down surfaces frequently in addition to separation protocols.

It’s exactly the groups that are being told to stay home right now — infants, young children and older Coloradans — who most need the protection of vaccination, noted Stephanie Wasserman, executive director of Immunize Colorado (until this year known as the Colorado Immunization). The longer coronavirus concerns linger, the likelier the vaccine gap will grow in more mundane diseases like seasonal flu, she said.

A secondary outbreak of flu, measles or any other manageable disease on top of ongoing coronavirus infections “would be a body blow to our health care system and an economy that’s already on life support right now,” Wasserman said.

Wasserman noted that Colorado was “dead last” nationally in measles vaccination rates in the most recent measurements, and that it’s “horrifying to think about what’s going on with our measles coverage rates when we were already so far behind the eight ball before COVID.”

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Measles, mumps and rubella vaccine rates — the shot O’Leary said should be at about 95% for true herd immunity — dropped to 87.4% in the 2018-19 school year, the state health department reported last June.

As with many health issues, the current plunge in vaccination rates has both causes and implications related to racial and socio-economic inequities, state health leaders said. (Health department statistics show positive tests for COVID-19 are higher in Latinx residents than their proportion of the population, and death rates among African Americans are similarly out of proportion.)

“We know from data we have those same issues for immunization,” Wasserman said. “We know children on Medicaid are immunized at a lower rate than children with private health insurance; we know children of color generally have lower immunization rates than white children. So it’s layering more concerning issues on top of this base of health equity issues.”

Experts worry Colorado is open for diseases unseen in decades, like diphtheria

A relatively high rate of families skipping or postponing vaccination weakens Colorado’s defenses against future threats, O’Leary said. Some nations overseas center their immunization culture on national vaccination days with massive mobilization efforts. Those are being canceled to avoid COVID-19 spread.

“So there’s a big concern we’ll see outbreaks of diphtheria in the rest of the world, and we haven’t really had that here in decades,” O’Leary said. “There are various risks depending on what you’re talking about, but every one of those diseases is life threatening.”

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Seniors are also staying away from important shots, officials said, including flu vaccines, shingles, Streptococcus pneumonia, or boosting previous immunizations such as tetanus.

O’Leary said the task force currently forming will try to communicate a needed sense of urgency to parents and other caregivers. The expert-devised vaccination schedules cluster shots in two age groups, one from infancy to age 2, and the other around kindergarten. A delay of a month or two for kindergartners is acceptable if families catch up later, O’Leary said — but for infants, those first scheduled immunity shots are crucial.

Practices from large to small are doing their best to accommodate fears of coronavirus contamination, whether splitting the functions of offices like Pediatrics West, or scheduling “well” visits in the mornings and “sick” visits in the afternoons or by telehealth, O’Leary said. Parents need to make the same effort.

“Please, please, please, keep your appointments,” O’Leary said.

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