Vaccines: To Jab or Not to Jab?

In mid-November the parents of roughly 1,700 Maryland children received a letter telling them to come to court to either have their children vaccinated or else face fines or jail. Ouch.

The parents were, to put it mildly, furious. Some because they blamed the school system’s poor record-keeping, saying they never should have received the letter. But many had decided not to vaccinate their children because of safety concerns.

“The patient should have a choice,” Donna Hurlock, MD, a gynecologist and activist on issues of parental rights and privacy, told CNN on November 17. “I just don’t think Big Brother should have that much power.” Now, I’m not normally a fan of Big Brother—give me rugged individualism just about every time—but in this instance, I’m with him.

Granted, the tactics were over the top. But I also know that I wouldn’t want to send my children to a school district with 1,700 unvaccinated kids. Why? Well, because of a little thing called herd immunity.

Herd immunity is what really protects people from all those old-fashioned killer diseases that almost no one gets anymore, such as measles, mumps, whooping cough, and polio. If you vaccinate the “herd”—or most of the population—it breaks the chain of disease and protects the few who may not have been vaccinated due to health or religious reasons. In theory, the healthy masses get the jab to help protect our weaker members, who can’t be vaccinated due to illness or frail immune systems.

The problem is that when too many people go unvaccinated, it threatens the whole herd—even the vaccinated members. That’s because vaccines aren’t perfect. For example, one dose of mumps vaccine is only 75% to 91% effective. (Two doses became standard in 1989, but even that is not 100% effective).

If enough people in the population are unvaccinated, disease can spread—and then lots of vaccinated people can get sick too. Case in point, in a 2006 mumps outbreak in Iowa involving more than a thousand people, 12% of people who got sick had one dose of the vaccine for that same illness, 51% had two doses, and 6% were unvaccinated (vaccine status was unknown in the others). A 2005 measles outbreak affected 34 people, 88% of whom were unvaccinated, largely due to the parents’ health concerns.

After years of reading vaccine studies, I’m OK with my children getting vaccinated for the biggies—measles, mumps, rubella, diphtheria, whooping cough, etc. Those vaccines have been around for years and are often updated with new technology to help reduce side effects (for example, in 1996 the DTP shot became DTaP, when the whole-cell pertussis component was switched to acellular pertussis to cut down on side effects such as fever, swelling, and convulsions).

Newer vaccines? Well, that’s where I get cautious. I remember the rotavirus vaccine that was introduced in 1998 to prevent infant diarrhea, then pulled from the market in 1999 due to a rare, potentially life-threatening side effect. In 2006 a new and improved version hit the market, but I admit I’d probably skip that one.

The chickenpox vaccine first came out in 1995, and I put off vaccinating my kids for a few years to see if there were any side effects that hadn’t emerged in clinical trials. So far, so good, and I finally had them vaccinated.

Caution is a good thing, but sometimes it’s good to be one of the herd. When too many people opt out of vaccines because of a fear of rare side effects, it can break the chain that protects us all.