BY AMBER SMITH
How do we know, for sure, that vaccines don’t cause autism?
“Science has a funny thing about absolutes. If you ask a scientist, ‘Can you say for sure?’ the scientist will say, ‘I can’t go beyond my data. But the data, which involves multiple studies and thousands of children, convincingly shows that it’s not associated. I believe it’s not associated,’” says Paul Parkman, MD.
Parkman, now 86, is a Weedsport native and Upstate graduate who helped isolate the rubella virus in the early 1960s, then developed an antibody test and vaccine. He started his career as a doctor at Walter Reed Army Medical Center and served as director of the Food and Drug Administration’s Center for Biologics Evaluation and Research from 1987 to 1990.
In 2005, he gave an oral history at the National Institutes of Health in which he shared his worry of people who mistrust vaccines. He told the story of rubella, also known as German measles. It was thought to be a mild childhood disease, which had to be differentiated from the more serious rash-causing diseases of measles and scarlet fever. Only later did doctors learn that rubella caused pregnant women to miscarry or to deliver babies with severe congenital deformities.
Parkman remembers the last major rubella epidemic, in 1964. If a pregnant woman developed a rash, she would worry about the potential for miscarriage and whether her doctor would recommend abortion, so she would not deliver a baby damaged by the virus. Women feared the disease, with good reason.
Parkman says some parents today mistakenly believe they don’t need to have their kids immunized. Young adults today weren’t alive to remember previous epidemics.
“Maybe the immunization of all the other children in your neighborhood will protect you,” Parkman continues in the oral history, “but if you and the lady next door and the guy down the street decide not to be immunized, you’ll have a problem again, sure enough.”
Reading Parkman’s words today, he seems to have predicted the growing measles epidemic with which the United States is now grappling.
When Parkman was studying rubella viruses, the epidemics seemed to come in waves, every six to nine years. So with a rubella vaccine available in 1969, government leaders at the Division of Biologics Standards of the National Institutes of Health and the Centers for Disease Control and Prevention made some decisions that proved wise. They had to decide who got the vaccine first.
“We made the decision to use it in children 1 year of age, the first time when you really could get good antibody responses. Before that, the antibody response can be interfered with by maternal antibodies,” he explains. “So, you start immunizing at one year of age up until puberty.
“If you really push hard and get all those kids immunized, you’re going to stop the epidemics, because children are the ones who really spread the virus.
“And we did it. If you look at those epidemic curves, they bumped up and down every six to nine years. After 1969, no more big epidemics.”
An estimated 12.5 million Americans got rubella during the epidemic from 1964 to 1965, including 11,000 pregnant women who lost their babies, according to the CDC.
Once the vaccine was in widespread use, the number of people infected with rubella dropped. Today fewer than 10 Americans are reported with rubella each year.
The MMR vaccine protects against measles, mumps and rubella. The Centers for Disease Control and Prevention recommends children receive two doses, the first between 12 and 15 months of age, and the second between 4 and 6 years of age.
Measles, mumps and rubella are contagious, viral childhood infections that can be avoided through vaccination.
Measles can be serious, even fatal. Measles outbreaks have been reported across the United States, with the majority of cases occurring in people who have not been vaccinated.
Mumps causes swelling in the glands that produce saliva, and complications can lead to hearing loss. Mumps was common in the United States until vaccination became routine.
Rubella (German measles) is usually not as severe as measles, and its symptoms are generally so mild they may be difficult to notice, especially in children. The virus can cause fetal death or serious birth defects if contracted by a woman who is pregnant. The CDC declared rubella eliminated in the United States but cautions that children need to be vaccinated to prevent its re-emergence.
This article appears in the fall 2019 issue of Upstate Health magazine. Click here for the full online version of the magazine.