VACCINATION TO PREVENT CERVICAL CANCERS
Background: Human papilloma virus type 16 (HPV=16) and type 18(HPV18) cause 70% of cervical cancers throughout the world.
A vaccine of HPV16 and HPV18 combined with HPV6 and HPV 11was given to 6000 females between 15 and 26,in 3 doses over 6 months. HPV6 and HPV11 were added because these viruses are present in genital warts.
Results: The women were followed for 3 years. Effectiveness was 17% against high-grade cervical lesions. One thousand women got pregnant and of those delivering a live baby, 5 congenital anomalies were found in the vaccine group and none in the placebo group. Follow up was relatively short under 4-5 years.
Discussion: The vaccine is effective in high-grade lesions but most lesions found were low grade often reversible since most HPV infections are transient. Giving girls four viruses to prevent cervical cancers could lead to other disease entities. This vaccine is now pushed for all girls 15 years of age. Seems like overkill without long-term trials longer than 5 years. What do you think?
VACCINATION TO PREVENT SHINGLES - New England Journal of Medicine, March 29,2007
Backgound: Varicella-zoster virus (VZV) causes chickenpox in children and shingles in adults. Over a lifetime 30% of people will get shingles.
People over 60 are 8-10 more likely to get shingles than younger adults. It is more likely to occur in people with compromised immunity. Pain after the eruptions disappear can last for many weeks or months. This post shingles pain occurs in over 40% of people over 60.
The most common sites are on the face and thorax. The virus hits one dorsal-root ganglia and the nerve root loses its myelin. The chickenpox vaccine for children is an attenuated (weakened virus). Because older adults don’t respond well to vaccinations, a new vaccine was made with a LIVE virus that would result in 10 times as many plaques as the chickenpox virus. It was felt that this dose of live virus would boost the immunity to lower the risk of shingles.
Results: 38,000 seniors over 60 were given the vaccine and followed for 3 years. It worked best on seniors under 70 years of age. There was a
51% lower incidence of shingles (So the vaccine did not prevent 49% of cases of shingles.). The FDA approved the vaccine on May 25, 2006.
Discussion: Seems like 49% of adults are not protected from shingles after the vaccination. Also adults over 69 don’t get much protection. No data on repeat vaccinations yet. Several uncertainties exist. Should adults in their 50s get the vaccination as well as those over 69? Insert says cardiac events re more common in those receiving the vaccination. The vaccine is not licensed for use in adults whose immune systems are compromised, yet these are the adults that need the protection. Interestingly, adults who had shingles were excluded from the study.