Pertussis Immunity May Wane, But Vaccine Still Offers Protection
Nov 30, 2012
Today I wish I hadn’t bothered reading the immunization news. Today I would much rather be dancing around to holiday music and breaking out some festive decorations. Because today, like many other days this year, I continue to read articles that focus on the impact that pertussis is having around the country and even around the world.
In one article, Kristen A. Feemster, M.D., M.P.H., explains that
“cases of pertussis, or whooping cough, have more than tripled in the past five years, with 2012 on track to be the most severe in over a half-century. More than 37,000 cases have been reported so far – 37 times the number in 1976, which was the lowest since the introduction of vaccines dramatically reduced prevalence of the disease.”
As a parent, I’m concerned about pertussis and here’s why:
It’s highly contagious. And since this is an airborne disease, it’s difficult to limit exposure if pertussis is circulating in your community, unless you intend to wear a mask 24/7.
It often goes undiagnosed. How many people have a persistent cough and don’t seek medical treatment? And when people do seek treatment for a cough, it’s likely that pertussis is not typically the doctor’s first consideration. Even if the doctor has reason to consider pertussis, there are often challenges in accurately diagnosing pertussis. In other words, it’s likely that people are walking around, exposing others to pertussis without being aware they are doing so.
There is no magic cure for this “100 Day Cough”. Doctor’s do what they can to treat the infection and the symptoms. While this disease may be unpleasant and inconvenient for most adults, it can be extremely dangerous and seriously life-threatening for children.
And here’s the kicker of them all….
Vaccination is not a guarantee that you won’t fall ill with pertussis.
The unfortunate reality is that the vaccine that protects against pertussis is not one of our most effective vaccines. As Dr. Feemster explains,
“in the 1990s, the U.S. switched from what was known as the “whole cell” pertussis vaccine to one with fewer side effects, referred to as the “acellular” pertussis vaccine. The older, whole cell vaccine had more antigens, or parts of the bacteria, for the human body to build immunity against. This produced a stronger immune response, but with more side effects. The new vaccine traded some immunity for fewer side effects. This “acellular” version effectively prevents disease, but immunity wanes over time, which means that we can become susceptible to infection again. As a result of the vaccine being modified years ago to ensure a greater degree of safety, it appears that it’s not as effective.”
And to make matters worse, most people are unaware that any immunity they may have received (as a result of getting the disease or getting vaccinated) will wane over time. In fact, just this week, the Journal of the American Medical Association released the first-ever study to test the long-term effectiveness of the current pertussis vaccine. Researchers stated that although the vaccine does work, children had the strongest protection in the year after their last shot (with 98% immunity), whereas five years later that immunity tends to drop (to about 71%). These results support a previous finding from September in a New England Journal of Medicine study, which also shows immunity from the whooping cough vaccine fades sharply over time.
So, why vaccinate?
Well, despite the apparent limitations of the vaccination, receiving a vaccine that may only be 71% effective five years after receiving it is still better than not vaccinating, having 0% chance of protection and relying on a decreasing level of community immunity.
Consider this…if your child contracts pertussis, one of three things may happen:
- Your child suffers with symptoms, but eventually recovers.
- Your child suffers with symptoms, and eventually recovers with health issues or permanent disabilities.
- Your child suffers with symptoms, and eventually succumbs to this dangerous disease.
While most parents want to believe that their child would be the one to make a complete recovery, isn’t it better to try to reduce the risk of contracting pertussis in the first place by ensuring your child is vaccinated?
Here are some additional facts to consider:
- Most deaths that occur as a result of pertussis infection involve infant children who are too young to be vaccinated, therefore they rely on the protection of others.
- It’s estimated that household members and caregivers are responsible for 76%-83% of the transmission of pertussis to infants.
- An unvaccinated child is 8 times more likely to fall ill with pertussis than a vaccinated child.
- If a vaccinated individual where to contract pertussis, it is expected that the case would be milder than if they were not vaccinated.
A simple viewing of Real Families Talk Pertussis, now airing on What to Expect: Healthy Mom, Healthy Baby, highlight the experiences of three families whose children were diagnosed with pertussis at a young age. In the first video, you meet seven-year old Shea. Her mother explains how a pertussis infection as an infant left her daughter to suffer with cerebral palsy, a physical disability she will have for the rest of her life. In the second video, the father of eight year old Isabel comes close to tears as he explains how they almost lost their daughter due to pertussis. And then a young mom, who suffered with whooping cough herself during labor, talks about how difficult it was to say goodby to the one person who made her life complete… her beautiful infant daughter Kaliah.
If every person could hear these words of caution from families who’ve experienced pertussis first hand, I believe we could help educate a greater number of people about the importance of pertussis vaccination.
Please help us take pertussis out of the picture and spread the word about the importance of Tdap b0oster shots for everyone. A baby’s life may just depend on it.
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