Despite the role that vaccines play in drastically reducing the incidence of varicella cases since the vaccination became available in 1995, “chickenpox parties” — where children are purposely exposed to the varicella zoster virus in hopes of immunizing from them a more serious infection in adulthood — persist.
In some cases, pox party organizers are part of the anti-vaccination movement. They see these viral gatherings as a legitimate route to avoiding conventional immunization. For other parents, it is a matter of underestimating the risks for a potentially fatal infection.
William T. Gerson
“People don’t really know a lot about chickenpox — they don’t know a lot about any of these illnesses, particularly when we see so few of them due to vaccines — but the idea that’s out there is that it’s just a benign illness,” William T. Gerson, MD, a clinical professor of pediatrics at the University of Vermont College of Medicine and Infectious Diseases in Children Editorial Board member, said in an interview. “I remind them of what the previous statistics were in terms of annual deaths — 75 to 100 — and of the hundreds of remissions for complications, and the bad complications of encephalitis and cellulitis, and that we now have an extremely safe and effective vaccine. So it’s hard to think that exposing someone to a known pathogen is a good idea.”
According to the CDC, complications associated with varicella include pneumonia, bleeding problems, infection or inflammation of the brain, group A streptococcal infections, sepsis, bone infections and, in some cases, death. Infants, adolescents, people with weakened immune systems and pregnant women may have more severe symptoms and could be at greater risk for complications.
Meanwhile, the varicella vaccine poses a lower risk for adverse health events than natural infection, with most people experiencing no side effects. Although some people who have been vaccinated against chickenpox still contract the virus, the CDC has reported that symptoms tend to be milder, with fewer blisters and a mild or nonexistent fever. According to data from the Texas-based Immunizations for Public Health, a mild rash or several small bumps may appear in 1% to 4% of vaccine recipients, while in less than one in 1,000 vaccine recipients a seizure caused by fever may occur.
“Varicella vaccine is a live weakened virus and does cause some low-grade fever, rash from the vaccine and other minor adverse events,” Kathryn M. Edwards, MD, the Sarah H. Sell and Cornelius Vanderbilt chairwomen in pediatrics at Vanderbilt University’s vaccine research program, said in an interview. “However, natural varicella infection is not weakened or attenuated, and it can cause severe adverse events, including death.”
Kathryn M. Edwards
Edwards, an Infectious Diseases in Children Editorial Board member, noted that it is important to emphasize to patients and their families that natural chickenpox infection — or that of any other virus — should be avoided in all situations.
“The risks associated with vaccine are far less than those that we see from natural disease,” she said. “Condoning the practice of exposing children to natural varicella when it can be prevented by vaccine is medical malpractice.”
When discussing the vaccine with parents who are “anti-vaxxers,” or may have been influenced by myths and falsehoods regarding immunization, Edwards said such questions, and fears, should be addressed “carefully, respectfully and thoughtfully.”
Gerson said that, although it is important to counter myth with science-based information, it is sometimes more fruitful to address the source of parent or caregiver fears or misgivings directly.
“I find the trouble is that often their issues are not rationally based in science or medicine, so trying to get at what really bothers the individual about vaccines is often useful,” Gerson said. “Some have misunderstandings that you can correct, and they then will alter their views.”
He added that, with its 98% success rate in preventing chickenpox, after decades in which 4 million people would contract the virus annually in the United States, the varicella vaccine may be, in some ways, a victim of its own success.
“When we’re effective with the vaccine, and people haven’t seen the illness, they don’t really have any knowledge of how bad they could be,” Gerson said. “People haven’t seen polio, so they don’t really know that concern, so they wonder why we do it.” – by Jason Laday
CDC. Chickenpox (Varicella). Complications. www.cdc.gov/chickenpox/about/complications.html. Accessed: January 7, 2016.
CDC. Chickenpox (Varicella). Transmission. www.cdc.gov/chickenpox/about/transmission.html. Accessed: January 7, 2016.
CDC. Chickenpox (Varicella). Vaccination. www.cdc.gov/chickenpox/vaccination.html. Accessed: January 7, 2016.
Disclosures: Gerson and Edwards report no relevant financial disclosures.