Chickenpox/Shingles exposure guide
Zoster is one of the eight herpes viruses known to infect humans. The primary illness is varicella zoster, more commonly referred to as chickenpox. After the course of the chickenpox illness, the virus goes dormant in the nerves. It can resurface years later as Herpes Zoster, more familiarly known as shingles.
While there have been some exposures at various schools, I haven’t had an actual case of chickenpox among my patients for over a year. These days I get way more calls about shingles than I do about actual chickenpox. Of course it isn’t my little patients with the illness. Usually it is a relative who has been diagnosed with shingles and the parents are wondering if it is safe to visit or if their child has been exposed. This post will give you the scoop about both Shingles and Chickenpox including exposure information.
Don’t try to read this when you are sleep deprived, it might make your head spin.
When the Varivax (chickenpox vaccine) came out in 1995, it took us a few years before we started giving it widely. We did an about face one season when we had hordes of chickenpox patients who were absolutely miserable. There didn't seem to be a sensible answer as to why we shouldn't simply give the shot to prevent it. The answer that "we had them and survived" seemed a little weak. While it is true that most chicken pox sufferers simply have a very unhappy week, complications do occur. Even the moderate cases can have painful lesions in the genitals and mouth. Some folks get them in the eyes and need round the clock eye drops. Some of the lesions end up leaving scars. At the very least you have a sleepless, itchy week and will need to take time off of work. One of the bigger concerns about the disease is the potential for future shingles. Here in California, as of July 2019, if you are going to be in the school system, 2 doses are now required before getting into kindergarten.
One of the best things about getting the chickenpox vaccine and avoiding the misery is the fact that studies indicate that future occurrence of shingles may be less likely in a patient who had the Varivax than someone who had the actual chicken pox. In all honesty that question probably won't be answered for another 40 years or so, when the first wave of kids who got the vaccine become middle aged. Keep your fingers crossed. At the very least, in our office, almost all of our patients are vaccinated and cases of shingles are exceedingly rare.
Infants are thought to have some maternal protection to the chickenpox virus that starts to wane when they are about 7 months. The protection is probably gone by a year. The first dose of the shot is usually given between 12-15 months. Unlike the MMR, Varivax is not recommended before the age of a year even if traveling or your child has been exposed. A booster is given between 4-6 years. For children playing catch up who are getting the Varivax for the first time, the minimum interval between doses for children 7-12 is 3 months. For kids who are over 13 the minimum spacing between the 2 doses is only 4 weeks.
If you are a parent who isn’t sure if you have had them as a child, there is a blood test that can determine if you are immune or not.
Kids are contagious a day or two before they get any lesions. They may have a low grade fever and be cranky. It is very likely that they are out and about in school, daycare or activities during this period spreading this virus to anyone who is not immune. It is what it is. No reasonable person expects you to keep your child home every time they are cranky. They remain contagious until all of the lesions have crusted over. That usually takes about a week. Most kids these days are vaccinated so there is good herd immunity working in our favor.
So there you were in the park, playing with patient X. You get an apologetic call the next day from patient X's parent that their child seems to have come down with chickenpox. If the kids were having close interaction with each other, it is likely that your child was indeed exposed. The chickenpox virus is very contagious. It is airborne and can live on some surfaces. If your child is vaccinated or already had the illness, you likely don't need to worry too much. The vaccine is about 85% effective, however the CDC bumps that up to 98% after the second dose. The rare vaccine failures tend to get much lighter cases. If your child in not immune you are now on alert.
From the first moment of exposure, the incubation period is usually 2 weeks but can range from 10-21 days. If 3 weeks go by with no sign of anything you are likely in the clear. Just because your child has been exposed is not a reason for you to keep them home from school or daycare and for you to miss work. They may or may not catch it. Someone who is immune is not likely to carry it.
If your child has been exposed, be on the lookout for any signs that your they might be succumbing. The words "I want to go take a nap now" may be a red flag. If they get a fever you should probably issue a warning to any friends or caregivers as you wait to see if spots appear. If your child does come down with it they are now patient X and were likely contagious a day or so before the first sign of a rash.
The chicken pox rash is pretty distinctive. Once the chickenpox rash appears, it goes through three phases:
New bumps continue to appear for several days, so you may have all three stages of the rash — bumps, blisters and scabbed lesions — at the same time. They usually start on the trunk but then spread. When they scab over they are very itchy.
Be aware if you are traveling out of the country that there are many places in the world where vaccination for chickenpox is NOT routine. Dr Schwanke is frustrated that we are not supposed to give an early shot for travelers. Most of the cases we see now a days are folks that were exposed while visiting family abroad.
As I mentioned earlier, after you recover from chickenpox, the virus can enter your nervous system and lie dormant for years. Eventually, it may reactivate and travel along nerve pathways to your skin - producing shingles. It is most common in folks when they are older adults. It may be stress related. One easy diagnostic trick is that the blistery and usually painful rash will usually not cross the midline of the body. About 10-20% of folks who had the chickenpox will end up with shingles.
Shingles can be spread only if someone comes into direct contact with the lesion. A healthy person who has immunity to chickenpox is generally not considered to be at risk. Someone with a compromised immune system or someone who has never had the chickenpox needs to be a little more cautious. If infected, they would catch chickenpox, not shingles, from the infected person. Over the years we have had a couple of patients who came down with cases of chickenpox that we traced back to a shingles exposure, but again, that is most unusual. It is NOT airborne. If the shingles patient keeps the lesions covered you can still go visit grandma.
For those of you over the age of 50 there is a new shingles vaccine that looks quite promising. It packs a punch. This is a 2 shot series. Most people complain of a sore arm and feeling fluish (hit by a truck) That is still better than getting the shingles, as most people who have ever had it will tell you.