The last time a Montanan suffered from measles, the Soviet Union still existed: Six cases were confirmed in three counties in 1990.

But recent outbreaks in the state of Washington have placed more than 30 Montanans at risk of contracting the disease from recent exposure.

No confirmed cases have been diagnosed in Montana, but local health professionals are wary of the future — and are laying much of the blame at the door of the anti-vaccination movement.

“If Flathead County got locked into space where it was right now and no one could leave or enter, the risk of measles would be very low,” Flathead County Public Health Officer Joe Russell said. “But people come and go and we aren’t isolated.”

More Americans have been diagnosed with measles in the first four months of 2014 than the last 18 years, with at least 129 confirmed cases. Of these, 12 were in Washington. Vancouver, B.C., has more than 375 reported cases in 2014. Along with measles, mumps, rubella and whooping cough have made comebacks in the United States.

Anti-vaccination or vaccine-neutral groups such as Shot Free in Montana and Montana Families for Health Freedom promote parents making informed choices about vaccinations and question the efficacy and safety of a regular vaccination schedule.

“We are not opposed to vaccines,” said Edna Kent, representative of Montana Families for Health Freedom. “We just want parents to make informed choices.”

Many of these groups attribute lowered rates of infectious disease to improved hygiene and insect control rather than shots. The ingredients used in making vaccines are another concern for many parents. Vaccine ingredients such as fetal bovine serum and chicken kidney cells lead parents such as Kent to be concerned about vaccine safety.

A famously touted claim from groups such as these is the link between the Measles/Mumps/Rubella vaccine to autism. A British physician, Andrew Wakefield, published a study linking the two in an English village in 1998.

No other study has found a link between vaccinations and autism, Russell said, but the fear persists.

“His postulate has been disproven again and again,” Russell said. “There is simply not scientific evidence, through any epidemiological study ever done, that vaccines cause autism.”

As parents hesitate on immunizations — on both sides of the political spectrum — more preventable diseases spread. Some of the groups wary of vaccinations believe their actions aren’t what is causing diseases like measles to proliferate.

According to the Center for Disease Control, measles cases peaked in 1958, when the United States reported more than 750,000 cases. A vaccine was developed and licensed in 1964 and measles cases dropped from 450,000 to under 30,000 in just four years. Small resurgences in the late 1970s and 1980s were quelled by doctors recommending a booster shot. Rates dropped from 27,000 cases in 1990 to nearly zero by the turn of the century.

Despite marked improvements in public health, doubts remain for many parents about the risk and efficacy of vaccinations.

“I get a lot of people calling me saying the vaccine does more harm than good,” Russell said. “Our response has tried to embed our message in the science.”

Montana has two exemptions for children regarding vaccinations. One, a health-based exemption, is applicable for both day-care facilities and public schools.

Many vaccines are based on egg proteins, so children allergic to eggs can be exempt. Russell said some parents decide to go through with immunizations anyway, having weighed the risks of allergies against not being vaccinated.

The other exception is a personal exemption for school-aged children. Whether for religious, holistic or family reasons, a printed and signed form exempts children from whichever vaccinations parents or guardians choose.

“The standards are extremely loose,” Russell said. “You don’t need a signed note from a pastor or a doctor. You get a form from the Internet, fill it out and that’s the end of it. This accounts for about 5 percent of school-age children.”

Of students in public school, 95 percent are at least partially vaccinated, he said. However, the Flathead Valley is home to many home-schooled children. Russell does not know how many of these children have been vaccinated.

While this lack of vaccinations is one alleged reason for the large whooping cough (pertussis) outbreak in the Flathead, another is simply that the vaccine currently used is far less effective than in years past.

The DTaP and Tdap vaccines (two separate cocktails of shots standing for diphtheria, tetanus and acellular pertussis) are given to children and adolescents, respectively. Because both use only partial cells of the Bordatella pertussis bacteria, the body cannot create a complete immunity. Those who have received the shot are still at risk for spreading the disease.

 The county has diagnosed 231 pertussis cases in the last 12 months, the highest since 2005, when more than 600 lab-diagnosed cases were documented. Russell considers the Flathead Valley lucky that no measles cases have made their way to the area.

Measles symptoms include coughing and high fever ,but the disease is known for its characteristic spotted rash that covers much of the body. Whooping cough, characterized by loud coughing and a “whoop” sound from a sharp intake of air, is especially virulent in children and can be fatal for babies.

The Centers for Disease Control estimates that vaccines have prevented 323 million illnesses and 732,000 deaths in the U.S. alone.

Un- or under-vaccinated people lower something called herd immunity. The basis of this immunity is that the more people are vaccinated, the lower the chances of an unimmunized person catching an infectious disease.

Kent said groups like her own have heard that rationale time and time again, but have yet to see any science to convince them vaccines are always worth the risk of inoculating children.

Russell said there should never be a doubt.

“We vaccinate because the risk of disease is far greater than the risk of something harmful coming from vaccines,” he said. “Look at the Spanish flu of 1918. It had a 2.5 percent mortality rate and traveled the world three times. We forget how disease affects us. Elderly in the Flathead Valley get flu and die every single year.”

Reporter Ryan Murray may be reached at 758-4436 or by email at rmurray@dailyinterlake.com.