Vaccine court
The VICP covers all vaccines listed on the Vaccine Injury Table maintained by the Secretary of Health and Human Services; in 2007 the list included vaccines against diphtheria, tetanus, pertussis (whooping cough), measles, mumps, rubella (German measles), polio, hepatitis B, varicella (chicken pox), "Haemophilus influenzae" type b, rotavirus, and pneumonia. From 1988 until 8 January 2008, 5,263 claims relating to autism, and 2,865 non-autism claims, were made to the VICP. 925 of these claims, one autism-related (see previous rulings), were compensated, with 1,158 non-autism and 350 autism claims dismissed; awards (including attorney's fees) totaled $847 million. The VICP also applies to claims for injuries suffered before 1988; there were 4,264 of these claims of which 1,189 were compensated with awards totaling $903 million.
Varicella vaccine
Some vaccinated children have been found to lose their protective antibody in as little as five to eight years. However, according to the World Health Organization: "After observation of study populations for periods of up to 20 years in Japan and 10 years in the United States, more than 90% of immunocompetent persons who were vaccinated as children were still protected from varicella." However, since only one out of five Japanese children were vaccinated, the annual exposure of these vaccinees to children with natural chickenpox boosted the vaccinees' immune system. In the United States, where universal varicella vaccination has been practiced, the majority of children no longer receive exogenous (outside) boosting, thus, their cell-mediated immunity to VZV (varicella zoster virus) wanes—necessitating booster chickenpox vaccinations. As time goes on, boosters may be necessary. Persons exposed to the virus after vaccine tend to experience milder cases of chickenpox.