Pediatric Associates of the NW Blogs

A Pox on Your Party

Jay S. Rosenbloom, MD, PhD
December 02, 2011 07:05PM

Chicken pox used to be a rite of passage.  Before the routine use of vaccine there were an estimated 4 million cases with 11,000 hospitalizations and about 100 deaths annually in the US.  Most adults remember having the chicken pox as a child and most cases were generally mild.  Chicken pox is usually spread by breathing infected droplets coughed by a sick person. The typical course would have fever to 102 degrees for the first 2-3 days while breaking out with 200-500 itchy blisters all over the body.  Each of the blisters would open and then crust over 3-4 days.  Anyone with chicken pox would be isolated until after they stopped getting new lesions, and the newest crusted and dried (usually 1 week).

Complications from chicken pox (or varicella) infection are more likely in infants less than a year, but even higher in people over 20 years old. Anyone with chicken pox can get a secondary bacterial infection in each of the blisters. Once someone gets the chicken pox, the varicella virus stays around in the nerve cells and can become reactivated, which we call Zoster. This can happen any time, but especially in times of stress or with illness. Zoster shows up as an extremely painful rash that can last weeks and can be dangerous in people whose immune systems don’t work well.

Given the fact that chicken pox is usually worse when patients are older, many parents in the past tried to make sure their children had chicken pox as toddlers.  The typical method of getting kids infected at this age was to have a well-child play with one that had just come down with the chicken pox.  These were known as chicken pox parties.

Recently it was revealed that not only are some parents choosing to continue this outdated tradition, but given the rarity of the disease now, they are also taking more extreme measures.  Parents of acutely infected children have the sick child suck on a sucker and then sell it to others (via US mail).  Why is this a bad idea? Not only is this illegal, it is also more likely to infect the children who suck on the sucker with diseases other than chicken pox.

Understanding how the chicken pox vaccine is made also helps us understand why chicken pox suckers and chicken pox parties are bad ideas. In the early 1970’s a Japanese scientist swabbed the active pox from an otherwise healthy child with chicken pox.  The virus was then grown in different kinds of cells, over and over, until it grew well in the lab but not well in humans.  This is called the Oka strain of the varicella virus.  When a child is vaccinated for chicken pox we inject a measured amount of live Oka varicella virus. Because we inject a strain of virus that doesn’t grow well in children, it makes it so that children don’t get the symptoms of chicken pox when they are exposed to the vaccine.

This means that parents do have a choice of pox parties.  Parents can go to a friend’s house and let their child play with an infectious playmate, getting an uncontrolled amount of virus, suffering through a week of itchy pox, each one a potential site of infection, or they can infect them with the strain that is too weak to cause the illness but doesn’t have the risk of the disease.

As a pediatrician it is always my goal to protect children from dangers.  When it comes to the chicken pox the vaccine isn’t perfect (what is?) but it offers good immunity without having to suffer through the disease with all of the risks associated.