If you’re a parent, you most likely had chickenpox as a kid. And if you’re reading this, you lived through it. It was probably miserable, but didn’t do any permanent harm. And if you have kids, you might be wondering “Why do we immunize our kids against an illness that everyone I know got, and had no problems with?”
Well, in part because not everyone was so lucky. Though most kids get a week of fever, fatigue, and the telltale itchy vesicles, complications of chickenpox include pneumonia and encephalitis, as well as skin infections. In fact, chickenpox used to cause over 10,000 hospitalizations per year, and around a hundred annual deaths. Some children have risk factors for chickenpox complications, such as Abby Petersen, who was found to be without a spleen after she died from pneumonia secondary to chickenpox in 2001. However, most deaths are actually in previously healthy children (such as this 15-year-old in 2009, and several of these cases).
Chickenpox vaccine has been tremendously successful at preventing the disease, as well as cutting complications and deaths. Since the introduction of the vaccine in the United States in 1995, deaths from chickenpox have been nearly eliminated, and a 2011 study in Pediatrics estimated that between 2000 and 2006, over 50,000 hospitalizations were prevented by the vaccine. Two doses of the vaccine are recommended, usually at 12-15 months and 4-6 years of age.
The vaccine is very effective, with one dose preventing severe chickenpox nearly 100% of the time. It is about 85% effective against all disease, meaning that there is a small chance that you could catch chickenpox after being vaccinated, but it's going to be a lot more mild, often just a few dozen spots instead of five hundred or more.
It's safe as well. Any vaccine can cause fever, which is common when the immune system is doing its job, and does not even need a fever reducer if the child is not very uncomfortable. There is the small chance, as there is with any fever of any origin, of a febrile seizure. A febrile seizure is a common event in children (about 4% will have one at some time in their life) and though scary, is generally not dangerous. Otherwise, besides soreness of the injection site, the most common side effect is a mild rash in about three to five percent of kids. This is usually only two to five vesicles, nothing compared to what the wild disease does to a child. More serious side effects are extremely rare.
So That's Chickenpox; What Is Shingles?
Shingles (also called zoster) is related to chickenpox, and in fact they are caused by the same virus: varicella zoster virus (sometimes called just varicella virus or zoster virus). Lots of names for similar things. How they are related is a bit complicated, so lets break down the order of events:
- 1.) As a child (usually), you catch varicella virus. Almost everyone catches it in childhood (that is, everyone growing up where the vaccine isn't used). You break out in those vesicles all over your body (sometimes even inside your body), and you itch like crazy. Most kids get over it in about a week, except for those that develop the complications I discussed above.
- 2.) After you recover, the fun is not necessarily over. The virus usually isn't usually cleared from the body, and instead goes dormant and lives in the nerve roots of most people, sleeping there in the dorsal root ganglia (clusters of nerve cells near your spine). If you have had chickenpox, they are most likely sleeping in some of your nerves right now. Feel itchy?
- 3.) At some point in life, some virus reactivates, travels along the nerve it was sleeping in, and breaks out in a focused, painful cluster of lesions that we call shingles. This happens in 20-30% of people during their lives, often because their immune system is depressed for some reason (due to age, immunosuppressive medication, or possibly even stress). Shingles has a hospitalization rate of 1-4%, and causes 100 or more deaths per year as well. Shingles is considered to be more dangerous than chickenpox, in part because it hits an older population with more underlying health problems, though the number of deaths truly related to shingles may be overreported.
So that’s how shingles works. The good news is that our vaccinated kids are likely to have a much lower rate of shingles. The evidence for this includes studies (see here and here) looking at the frequency of shingles in vaccinated and unvaccinated children, as well as studies looking at immunocompromised children who are more likely to get shingles early in life. Vaccination is associated with much lower shingles rates.
Is Wild Chicken Pox Exposure a Booster Against Shingles?
It’s worth mentioning that some experts have hypothesized that taking care of our kids with chickenpox actually acts as a “booster” of sorts, and reduces the chance that a grown-up will get shingles. The idea is plausible, but not a compelling reason to not vaccinate our kids.
I’ve even been part of a discussion with a celebrity doctor who advocated that children should keep getting chickenpox disease for this reason, to help keep shingles in adults at bay. I can’t imagine a more backwards philosophy.
First, although the theoretical increase in shingles due to widespread reduction of chickenpox is reasonable and supported with some science the data simply hasn’t supported it as actually happening. Reviews of chickenpox and shingles epidemiology in 2008 and 2010 found no consistent evidence of an increase in shingles following widespread introduction of varicella vaccine, and a 2013 study published in Annals of Internal Medicine found that 1.) shingles had been increasing prior to the introduction of chickenpox vaccine 2.) widespread use of the vaccine did not affect the rate of increase, and 3.) the incidence of shingles did not correlate with state varicella vaccination coverage.
But even if there was an increase in shingles in older populations, I can’t imagine wanting our children to be sickened in droves so we grownups have a lower rate of shingles. It's a barbaric, dystopian idea. It is bizarre to me to think that nearly every child should suffer a week of illness, that 10,000 children should be hospitalized, and that 100 or more should die, so that their parents can reduce the the morbidity and mortality of shingles. Not to mention leaving these children with a 20-30% lifetime risk of shingles themselves.
It’s even less understandable when there is a safe shingles vaccine for older adults that cuts the rate of shingles by half.
This is precisely the opposite of how we should view chickenpox and children. Our children should have the benefit of growing up without chickenpox, and with a lower risk of shingles. Our kids shouldn't have to be ill to keep grownups healthy. Vaccinating against chickenpox protects our kids from being sick today, and gives them a healthier future.