Parenting is a tough business. You can do all the right things for your children and bad things can still happen to them. For instance, I can put a helmet and knee pads on my kid before I let her ride her bike at the park, but I cannot prevent the lunatic on a skateboard from careening down the hill and scaring my child so badly that she topples off the bike and lands in the mud. I did what I could to protect her, but darn it, it does not always work.
Bikes are one thing. Disease is another. I got a tough email this week from one of my closest friends. Her toddler, who she vaccinates on schedule, just got diagnosed with pertussis (aka whooping cough). My friend was, rightfully, a little bit mad. After all, she vaccinated her child. She vaccinated her other children. She and her husband got their Tdap boosters just like they are supposed to do. So what in the world happened?
To answer this, I turned to one of my pediatricians on call, Dr. Lara Zibners (who also happens to be my brilliant older sister).
Here, is her response:
I thought you were the vaccine advocate. Whatever. Once again, I will do your work for you.
The pertussis vaccine does not protect 100% of children who get it from pertussis. That is a fact. The number is closer to 85% and that immunity wanes over time. One of the first kids I saw with pertussis was a 7 year old fully immunized kid who contracted it at camp. His immunity was waning. He was in close quarters with a bunch of kids and someone with pertussis was there.
If 100% of kids and adults are immunized, the amount of pertussis circulating in the environment is virtually none.
If there are fewer people immunized, more of the illness circulates. Because the vaccine is not 100%, there is a chance that an immunized child is exposed and contracts the illness. If you are in an area with a pertussis outbreak, ALL children are at risk. (Amanda will note, here, that to protect her friend’s confidentiality, I will not name her location. But I did discover that there are a significant number of schools with low-vaccine rates in her area, and they have been seeing pertussis outbreaks).
But, if a kid is immunized, and still gets it, she should have a milder course of illness
simply because there is some immunity. There is less pneumonia, apnea, fewer days of coughing and less a chance of death. The vaccine may not 100% prevent pertussis but it still protects the child should she contract the illness, far better than a completely vulnerable child. In other words, a child who was vaccinated is more likely to ride out the illness over a shorter period of time at home, than hooked up to a ventilator or in the hospital/PICU for weeks. (And, yes, Amanda’s friend’s child was not hospitalized and seems to be doing pretty well).
It should be noted that getting pertussis does NOT make a child immune for life. The immunity wears off exactly the same as the vaccine. that is just the nature of pertussis. She still has to get the vaccine at the next scheduled booster.
The importance of vaccinating for an individual is to 1) try and prevent children from getting pertussis and 2) make the illness more mild if they do. As a society, the more people immunized, the less pertussis circulating in society. This is important because the most likely patient to die from pertussis is a baby who is too young for the vaccine
. It is frustrating, but the blame needs to be on those who have not vaccinated and have therefore allowed the disease to recirculate widely in the population. (It turns out my friend’s child is not quite 3 and therefore could not be fully vaccinated yet…that made her even more vulnerable to disease circulating in the community).
So there you have it. Vaccinated kids can get sick, but will most likely have a much more mild case of the disease. It is important that everyone maintain their immunity by getting booster shoots as recommended, so that we can protect each other and our community.