Researchers say healthcare costs and lost productivity add up when vaccines aren’t given. Antivaccination groups dispute the findings.

People who don’t get vaccinated are not just expressing a political view or voicing health concerns.

They are a drag on the economy.

That’s according to a study released this month by the University of North Carolina (UNC) at Chapel Hill.

The study, published Oct. 12 in the journal Health Affairs, examined the actual cost of inpatient and outpatient care as well as medications and the value of productivity lost from time spent seeking care.

The study was funded by Merck, a leading producer of vaccines.

The researchers said people who do not get inoculated for diseases that can be prevented by vaccines cost the U.S. economy more than $7 billion a year.

The bill for diseases that vaccines can prevent is $8.95 billion annually. Unvaccinated individuals account for 80 percent of that figure, or $7.1 billion, the researcher said.

The most expensive preventable disease is the flu virus, which in 2015 accounted for nearly $5.8 billion in healthcare costs and lost productivity.

Read more: The 6 most important vaccines you may not know about »

Sachiko Ozawa, Ph.D., associate professor at the UNC Eshelman School of Pharmacy, led the research team that studied 10 vaccines recommended by the Centers for Disease Control and Prevention (CDC).

Those vaccines protect against hepatitis A, hepatitis B, the herpes zoster virus that causes shingles, human papillomavirus, influenza, measles, mumps, rubella, meningococcal disease, pneumococcal disease, tetanus, diphtheria, pertussis, and chickenpox.

“We believe our estimates are conservative and highlight the potential economic benefit of increasing adult immunization coverage and the value of vaccines,” Ozawa told Healthline. “We hope our study will spur creative healthcare policies that minimize the negative spillover effects from people choosing not to be vaccinated while still respecting patients’ rights to make informed choices.”

The CDC estimates that 42 percent of U.S. adults received the flu vaccine during the 2015-2016 flu season. Other major illnesses with substantial economic burdens include pneumococcal disease, such as meningitis and pneumonia — which tallied nearly $1.9 billion in costs — and herpes zoster that causes shingles, which cost $782 million.

Researchers said the funding by Merck did not create a conflict of interest.

The researchers used a standard cost-of-illness methodology, and the primary data sources for the study (the Medical Expenditure Panel Survey and the Nationwide Inpatient Sample) are publicly available databases that could be viewed by anyone, Ozawa said.

“We have disclosed all the data inputs, analysis, and methodology in detail in the paper, which was peer-reviewed, and in the online supplement so the results are reproducible,” he said.” We present the results without any modifications by the funder.”

Why did the study cover only one year?

“Our objective was to estimate an annual economic burden using the latest available datasets,” Ozawa said. “We did not go back in time to look at changes in economic burden over the past decade, as many things may have changed during the decade in addition to vaccine uptake — such as the incidence of disease, the costs of treatment, and the effectiveness of vaccines themselves.

“For vaccine uptake, our analysis used an average of the latest years of data available. Uptake may differ from year to year based on demand-side (access, costs, etc.) and supply-side factors (supply, doctor recommendations, etc.).”

Read more: The vaccines every teenager needs »

Historically, vaccinations have saved lives and money.

In a two-decade study, the CDC analyzed the benefits of immunization during the Vaccines for Children Program era, 1994-2013.

“Coverage for many childhood vaccine series was near or above 90 percent for much of the period,” said Ian Branam, a CDC health communication specialist. “Modeling estimated that, among children born during 1994-2013, vaccination will prevent an estimated 322 million illnesses, 21 million hospitalizations, and 732,000 deaths over the course of their lifetimes, at a net savings of $295 billion in direct costs and $1.38 trillion in total societal costs.”

Some organizations believe that vaccinating children can cause serious medical problems, such as autism.

The results of the UNC study did not surprise a leader of Moms Against Mercury (MAM).

“We recognize it as the propaganda that it is,” said Janet Presson, R.N., M.Ed., a member of the board of MAM, which is based in North Carolina. “Vaccines can and do cause allergies, asthma, autoimmune disorders, neurological injury, autism, seizures, and even death. These serious health issues also cost billions.”

Presson also expressed reservations about the Merck research funding.

“Industry-funded research must always be carefully scrutinized, regardless of the industry involved,” she said in a Healthline interview. “When the addition of a single vaccine to the mandated schedule results in billions in profits per year to the manufacturer, the stakes become even clearer. The pharmaceutical industry has a history of falsification of research, lawsuits following numerous deaths and injuries from their products, and their products are recognized as a leading cause of death.”

In some cases, children are vaccinated at higher rates than adults.

That’s the case in California, according to reports from its Department of Public Health.

Based on data from the 2015 National Immunization Survey (NIS) for California, the estimated vaccination coverage (verified by medical records) among children 19 to 35 months was 75 percent for the combined seven-vaccine measure.

These include DTaP (tetanus, diphtheria, and pertussis), polio, measles-containing vaccine, Hib vaccine (prevents serious infections such as meningitis, pneumonia and epiglottitis, a severe throat infection), varicella (chickenpox), and pneumococcal.

The influenza immunization rate for California children 6 months through 17 years was almost 60 percent, according to NIS data. For the 2015-2016 school year, 93 percent of kindergarteners were fully vaccinated with all required immunizations, and 97.8 percent of seventh graders received the pertussis booster immunization.

“While some people may discredit the value of vaccines,” Ozawa said, “it is important to remember that U.S. adults are getting sick with vaccine-preventable diseases, and that vaccines can prevent them. Avoiding these illnesses can have not only a health impact, but also an economic benefit to society.”

Read more: Delaying vaccinations is not OK, doctors say »