The Immunity Community

PolioVaccineFeatured

We have the mythical comely milkmaid to thank for the development of the smallpox vaccine, which has saved billions of lives since English physician Edward Jenner developed it in 1798. It had long been noted that dairy workers tended not to contract smallpox when Jenner tested the theory that their immunity stemmed from exposure to the related cowpox. The vaccine he developed from that bovine virus, Variolae vaccinae, which gives us the word vaccine, proved effective, yet it would be a century and half before it gained wide use. In the 1950s, there were still 50 million cases each year, but the era’s concerted public health campaigns were so successful that the disease had been eliminated worldwide by 1980. Most Americans over the age of 50 still bear the nearly dime-size mark on the outside of their upper left arm that indicates their participation in that vast communal effort. The scar, which developed where the vaccine caused a pock to rise, serves as a mild reminder of the disfigurement this disease once caused.

This coming Sunday marks the 60th anniversary of another milestone in successful vaccination campaigns. On April 12, 1955, Jonas Salk’s polio vaccine was declared “safe and effective.” The announcement was made 10 years to the day after the death of Franklin Delano Roosevelt, who had been stricken with paralytic polio in 1921. In the year of the vaccine’s development, more than 25,000 Americans contracted the illness; post-vaccine, there hasn’t been a single indigenous, or “wild,” case in the United States since 1979. Salk’s vaccine used inactivated polio virus. In 1963 Albert Sabin’s more effective live-virus-based oral polio vaccine (OPV) became the inoculant of choice in the U.S., though one in every 2.4 million doses could actually cause polio, resulting in eight to 10 cases annually. Now that polio has been all but eradicated here, the U.S. has not used the live-virus vaccine since 2000, and infection from the vaccine is no longer possible.

In 90 percent of cases, polio passes like a flu, but in a small percentage it takes a much worse turn. Back in the early 1920s, when my father came down with polio as a toddler, he experienced partial paralysis and lived in a children’s hospital ward for more than a year. He suffered lifelong effects, including the characteristic “withered leg,” and walked with a pronounced limp. Others fared worse, confined to iron lungs that did their breathing for them or, like FDR, reliant on wheelchairs for the rest of their lives. My siblings and I were born before the development of most of the vaccines available today. We survived what were known as the standard childhood diseases—measles, mumps, chicken pox. Luckily, none of us contracted polio, and in 1955 our parents had us vaccinated without question, as did the parents of hundreds of millions of other children. With modern vaccines and community cooperation, the days of iron lungs, residential children’s wards and households under quarantine became a thing of the past.

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FDR in his wheelchair. Photo courtesy of Wikimedia

In increasing numbers, first-world parents are choosing not to have their children vaccinated, and illnesses that had become rarities, such as pertussis (whooping cough) and measles, have been making a comeback. According to MIT scientist Seth Mnookin, author of The Panic Virus: The True Story Behind the Vaccine-Autism Controversy, measles is the “most infectious microbe known to humanity.” Ninety-seven million people died of measles in the 20th century. Back in the 18th century, the elderly Louis XIV watched measles kill his first two direct heirs. It was up to five-year-old Louis XV, who survived the illness, to claim the throne.

Raising a child has become fraught, as self-proclaimed authorities escalate parents’ insecurities with nightmare stories and ironclad dos and don’ts.

My daughter had the full set of childhood vaccines before the discredited report claiming a link between the MMR (measles-mumps-rubella) vaccine and autism. Only chickenpox was still making the rounds, and when she got it, the parents of a couple of her preschool classmates sent their tots over to catch the virus so they’d gain immunity. Nowadays there’s a vaccine that gives immunity for chickenpox, too, and it also prevents patients from contracting shingles later in life.

Jonas E. Salk (1914-1995), American physician who developed the first effective Polio vaccine inocul
Doctor administering the polio vaccine. Photo courtesy of Everett

Herd immunity occurs when enough individuals have immunity to a disease to prevent an outbreak. The threshold is different for different diseases; in measles it’s 90 to 95 percent. But in all cases, for herd immunity to work, a very large majority of people must participate. It’s the only way to protect the few who are too young for vaccines, or cannot receive them because of allergies or compromised immune systems. This minority counts on an immunity community.

A relative handful of 40 annual measles cases in France in 2007 had swelled to 15,000 cases by 2011, as more parents began to choose not to have their children immunized. The United States is seeing a similar trajectory, as measles outbreaks have occurred in communities with a significant number of unvaccinated people, including an Amish stronghold in Ohio and several areas of California where the fear of vaccines has taken a statistically significant hold. Extrapolations of the French numbers would bring us to 70,000 cases in the same time frame.

It’s easy to make fun of neo-hippies eschewing “toxins,” as Jimmy Kimmel did when he joked that “anti-vaxxers” are more afraid of gluten than smallpox. But the fear driving the movement is nothing to sneeze at, as the unvaccinated inch our society toward a potential medical crisis. Public health officials are at a loss as to how to stem the tide. Education efforts have even backfired—at least one extensive study has shown that the more people are talked to about vaccines and childhood illnesses, the more they fear vaccines. The “anti-vax” movement has gone hand in hand with an increase in the “parenting” industry. Raising a child has become fraught, as self-proclaimed authorities escalate parents’ insecurities with nightmare stories and ironclad dos and don’ts. The internet in particular can offer people refuge for their beliefs, where misinformation proliferates, irresponsible claims are not reviewed by reliable authorities and it’s safe to demonize others.

Polio_connects_sideCertainly I remember worrying about my daughter’s course of OPV doses when she was such a tiny and vulnerable being. The scary thing about the statistics—one case of polio in every 2.4 million doses—was that somebody’s child was going to be that one. I just hoped my daughter would be one of the 2,399,999 others—and she was. She had the MMR without any adverse effects, but a much younger cousin had an allergic reaction and was not able to get the booster dose. As it turned out, when my daughter began working in the medical field (where immunizations are required) she discovered that the MMR had not actually “taken,” and has had to repeat the vaccinations at least twice. Luckily, for most of her life she has been protected by herd immunity. That younger cousin should also be protected by the herd, but she lives in a “community” where anti-vaccination rates are high, and recently had to stay out of school when a teacher contracted measles.

I put quotes around community because it’s a buzzword that I approach with skepticism. There’s a contradiction in claiming a sense of community by refusing to vaccinate your own children while relying on enough other people to follow vaccination schedules to keep disease rates in check. I support public health initiatives such as vaccine programs. I understand parents’ fears. But I question a decision that depends on others to do what you decline to do. As Eula Biss explains in On Immunity, with a successful vaccination program a “privileged one percent are sheltered from risk while they draw resources from the other 99 percent.” In the public health model, those privileged few are supposed to be those who can’t be vaccinated. This imperative to protect the vulnerable is community in the true sense.

Feature photo courtesy of Wikimedia