Dwindling vaccination rates threaten return of deadly diseases

We’re talking about scourges like measles and polio, which are now making a comeback all over the world due to declining vaccination rates.

The COVID pandemic made things worse — disrupting normal vaccination efforts and stoking the already dangerous anti-vaccination movement, according to epidemiologists.

The problem is especially worrisome in rural Arizona — with the non-reservation portions of Gila, Navajo and Apache counties reporting some of the state’s lowest childhood and COVID vaccination rates, according to the Arizona Department of Health Services.

As if that’s not bad enough — the Arizona Legislature this year enacted additional obstacles to expanding vaccine coverage. Arizona has long made it easier than most other states for kids to skip recommended vaccines. Parents can exempt their children from vaccines without really offering a reason. Many other states allow a child to enroll in school without required vaccines only if they have a medical exemption or an exemption based on a specific religious belief — like Christian Scientists.

The budget bill this year banned “COVID-19 vaccine passports,” which require proof of vaccination for things like international travel and admittance to high-risk businesses and events. It also prevents schools from requiring students to have COVID-19 or HPV vaccines — although the federal Food and Drug Administration hasn’t yet approved a mandatory vaccine for schools. The new provisions also add a whole series of additional requirements before the department of health services can add any new vaccines to the required list.

The use of exemptions has skyrocketed over the past few years,” reported the Children’s Action Alliance. “Unsurprisingly, our schools are rapidly losing herd immunity to diseases that pose a serious risk to children, older adults, immune-compromised individuals, newborns and pregnant women.”

Even before the drop in vaccinations for measles, mumps, rubella, varicella and hepatitis, Gila County’s vaccination rates had fallen below the levels needed to confer “herd immunity,” which can prevent isolated cases from starting an epidemic. The herd immunity level is based on how easily a particular virus spreads. For COVID, you need a vaccination rate above 70%-85% to protect the whole group. For polio — which is much harder to catch — you only need a vaccination rate of 80%. But for measles — the fastest spreading virus on record — you need 95%, according to a report on the childhood vaccination crisis by the Georgetown University Health Policy Institute.

Low levels of COVID vaccinations mirrored the low rates for an array of preventable childhood diseases.

For instance, 73% of Arizona residents have at least one COVID shot. But in Gila County only 51% have gotten a COVID shot. In the non-reservation portions of Navajo and Apache counties only 53% have gotten at least one shot.

So many Gila County children have skipped their vaccines that we’ve lost “herd immunity” for diseases like the measles. Statewide, 91% of kindergartners have had their measles-mumps-rubella (MMR) shot. That’s well below the targeted rate of 95%. But it’s even worse in Gila County — with just 86% vaccinated. In Apache County 89% are vaccinated and in Navajo County just 87%.

So if a case of measles does crop up on campus — it would likely cause an outbreak.

The same kinds of figures apply to Hepatitis B, with vaccination rates of 93% statewide, 94% in Apache County, 93% in Navajo County and 90% in Gila County, according to the state Department of Health Resources.

We’re doing better when it comes to protection from polio — but that’s only because polio spreads much more slowly and so the herd immunity threshold is lower. Statewide, 91% have gotten a polio shot — compared to 88% in Gila, Apache and Navajo counties.

Only about half a percent of the exemptions are based on medical criteria — like a potential allergic reaction to the vaccine. In Gila County, a worrisome 11% of parents have claimed an exemption based on personal belief and another half a percent based on medical issues.

The trend could easily prove deadly in coming years.

A decades-long, worldwide vaccination effort wiped out smallpox in 1977. The disease once killed about 4 million people every year and incurred billions in annual medical costs and disability.

But other efforts to eliminate deadly diseases through vaccination have faltered. We nearly eliminated measles in this country — but it continued to circulate in other countries with low vaccination rates. Now, it has returned to the U.S. The World Health Organization reported that in 2018 the estimated 10 million measles cases worldwide caused 145,000 deaths — a 58% increase in just two years.

The death rate for measles hovers at around 3%-6% in developed countries and close to 30% during outbreaks — with several underway right now globally. The virus can kill by causing pneumonia, diarrhea and dehydration. It can also cause blindness, hearing loss and brain damage. Measles can weaken the immune system, leaving children prey to a host of other infections.

Measles has a high “reproductive number,” which reflects the average number of other people a sick person infects. The reproductive number for COVID is two or three. The reproductive number for measles is 12-18, thanks largely to the time the virus can remain in the air or on surfaces and still infect someone.

The same thing applies to polio, which once killed 3,000 U.S. children annually — leaving thousands of others paralyzed for life. Vaccines virtually eliminated the disease in the U.S. — but it continued to circulate elsewhere. The virus has begun to spread again — with new cases reported in the United States.

Children from low-income families and families without health insurance are much more likely to skip the potentially life-saving vaccines.

“Vaccines are a safe and effective method of reducing the burden of infectious disease,” concluded the Georgetown study authors. “On an individual level, they prevent severe illness, death, and long-term consequences of disease such as neurological disorders. On the community level, they forestall dangerous outbreaks of infectious disease and save money that would otherwise be spent on treating preventable illnesses. Children who receive vaccines on the recommended schedule protect themselves and their communities while also decreasing future health care costs.”

The study concluded, “It is urgent that children and adolescents catch up on missed vaccinations now to protect themselves and their communities before they return to school, camp, sports and other in-person settings.”