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Widespread vaccination coverage among children is responsible for reducing or eliminating 14 serious childhood diseases in the United States. Despite this success, some parents remain concerned about the health effects of vaccines, and choose to keep their children unvaccinated. When population rates of vaccinations remain high enough, even unvaccinated children are protected because everyone a...

Population-based seroepidemologic data on mumps have not been available in Israel since 1987, and the effects of mass immigration from the Commonwealth of Independent States during the 1990s have not been investigated. We conducted a seroprevalence study of mumps antibodies among 353 Israeli military recruits aged 18-19, based on a representative sample of sera collected in 1999. The overall se...

The spread of infectious disease through communities depends fundamentally on the underlying patterns of contacts between individuals. Generally, the more contacts one individual has, the more vulnerable they are to infection during an epidemic. Thus, outbreaks disproportionately impact the most highly connected demographics. Epidemics can then lead, through immunization or removal of individua...

OBJECTIVES Because of the herd-immunity phenomenon, the benefits of immunization against hepatitis A extend beyond those received by those who are vaccinated. This analysis estimates the impact of herd immunity on the cost-effectiveness of routine hepatitis A immunization among US children. PATIENTS AND METHODS In an economic model, the costs and benefits of hepatitis A immunization were esti...

BACKGROUND Vaccination against the oncogenic human papillomavirus (HPV) types 16 and 18 will reduce the prevalence of these types, thereby also reducing cervical cancer risk in unvaccinated women. This (measurable) herd effect will be limited at first, but is expected to increase over time. At a certain herd immunity level, tailoring screening to vaccination status may no longer be worth the ad...

Newcastle disease is an economically important disease of poultry for which vaccination is applied as a preventive measure in many countries. Nevertheless, outbreaks have been reported in vaccinated populations. This suggests that either the vaccination coverage level is too low or that vaccination does not provide perfect immunity, allowing the virus to spread in partially vaccinated populatio...