Summary: Zostavax (the vaccine for Shingles) is a live attenuated vaccine. Because of this there are risks involved especially for those with weak immune systems and, in theory, women who are or might become pregnant. If you have gotten the Zostavax vaccine it’s important that you try to limit your exposure to these groups of people.
Dear Curtis: I recently got the shingles vaccine and on the way out the nurse mentioned not being around pregnant women. It didn’t dawn on me at the time but why is that? I’m a little concerned because I have a pregnant woman in my office and I don’t want to hurt her or the baby.
Lets start with how Zostavax works. It’s a live attenuated vaccine – which means that while the vaccine has been taken from a live virus it has been attenuated (or weakened) in a lab. They do this by actually growing the virus over and over again in a cell culture. What this actually does is it lessens the disease causing ability of the virus.
So, when the Zostavax is injected, your body still recognizes it as a virus – because it simply is – and immediately starts building antibodies to fight it. On the other side of the coin, the virus itself has a very low chance of causing you any harm or an infection because it is attenuated – or weak.
But, there are problems that crop up from time to time and that’s one of the reasons why you should have been asked before you got the vaccine if you have been sick recently. If you have then you are classified as being immunocompromized. A medical term for saying your immune system is weak. When you are in that state the vaccine can cause disease. Again – it’s no guarantee – but you are at higher risk.
Now, how does this tie into the pregnant woman whom you work with?
Theoretical Concerns With Zostavax
Well, most of the concern is theory right now but no vaccine manufacturer is going to take the risk of NOT warning you about the possibilities. In short, because the Zostavax is a live attenuated vaccine there is a theoretical risk that you can pass that virus onto other people. And, if those people are immunocompromized then there is a risk of infection. Pregnancy can be classified as immunocompromized as the mother is using a lot of her resources to keep the baby healthy inside her body.
One caveat: the biggest risk is a woman who is pregnant who has NOT had chickenpox before.
You were probably already explained this, but shingles is simply a latent chickenpox virus that has hung out in your body all these years and finally got a chance to ‘show’ itself with the hallmark painful rash of shingles. But, if someone close to you has NOT had chickenpox then getting some of the live attenuated virus you have floating around in your body could cause them harm.
And, before you dismiss an adult not having had chicken pox as a child (after all, every kid had chicken pox, right?) it is very possible. I have a friend who was in a big family as a kid who, for some unknown reason, never got chicken pox as a kid. He contracted chicken pox in his mid-40’s and it was extremely hard on him. In fact, the doctor who treated him said that he had only seen one other case of adult chicken pox like his when he was a doctor in the Navy and that, in adults, chicken pox can be fatal.
Part of the problem with what your asking and how I’m answering is because so much of the information is based on theory. No drug company really studies these things because it’s obviously unethical to test pregnant women to see how the vaccine will effect them and the baby. In short, use your best judgment but hopefully you understand now why they told you to be careful.