Thursday, September 1, 2011
Does Varicella Vaccine Eliminate Deaths From Varicella?
Medscape Infectious Diseases > Offit on Vaccines Paul A. Offit, MD Posted: 08/24/2011 Hi. My name is Paul Offit and I'm speaking to you today from the Vaccine Education Center here at The Children's Hospital of Philadelphia. I want to discuss a recent paper from the US Centers for Disease Control and Prevention looking at the effectiveness of the varicella or chickenpox vaccine. The varicella vaccine was first introduced into the United States in 1995. The study authors looked at deaths from varicella during the 5-year period before 1995, specifically from 1990 to 1994, and then they looked at deaths from varicella during the 3-year period from 2005 to 2007. In 2006, there was a second dose recommendation for varicella, but for the most part this is a comparison of a 1-dose vaccine schedule that was initiated in 1995 to look at the death rate before and after the introduction of the vaccine. The researchers found that overall, there was an 88% decline in varicella-related deaths: deaths from pneumonia; deaths from encephalitis; and deaths from overwhelming group A beta-hemolytic streptococcal infections that arose in the blisters caused by varicella. They also found a significant 97% reduction in the number of deaths in children younger than 6 years of age, and a significant 96% reduction in deaths in adults under 50 years of age. What we have learned from this is that, not surprisingly, the varicella vaccine works. Not only did it work in prelicensure trials to show that it was efficacious, but it also has worked in postlicensure effectiveness trials. We can only expect a further decline in deaths now that we have a recommendation for a second dose, initiated in 2006. This should result in another 10-fold reduction in cases and, I think, a virtual elimination of deaths. We should take our hats off to all those who were involved in the development of this lifesaving vaccine.
Posted by Dr Tan Poh Tin at 10:51 PM