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Background Varicella and herpes zoster (HZ), diseases both caused by the varicella zoster virus (VZV), are vaccine-preventable. However, the hypothesis that childhood varicella vaccination may increase the incidence of HZ hinders varicella universal routine vaccination (URV) implementation in many countries. Methods This non-systematic and narrative review of the literature considers the burden of varicella and HZ, and the effectiveness of the respective vaccines. We present the factors involved in the interplay between varicella vaccination and HZ incidence, including the roles of exogenous and endogenous boosting. We review HZ incidence model predictions, and compare these with real-world evidence, which has accumulated since varicella URV was introduced. Conclusion Although more research and longer surveillance are needed, available real-world evidence has not confirmed the model-predicted increase in HZ incidence, associated with childhood varicella URV. Although there is a rising incidence of HZ globally, this trend appears to be predominantly the result of an aging population. Vaccination against varicella in childhood provides significant benefits with respect to the medical, societal and economic burdens of the disease. Therefore, a theoretical concern of an increased burden of HZ with varicella vaccination programs should not prevent children from being protected against the disease.

The objective was to verify specific antibody response of varicella vaccinees to varicella-zoster virus (VZV) strains of different major clades and subclades circulating currently in Germany. The neutralization test and the fluorescent antibody to membrane antigen test measuring VZV glycoprotein (gp)-specific antibodies were used as methods. All VZV strains clustering into the main clades 1, 3 and 5 were neutralized by vaccine-induced antibodies and showed specific reaction with VZVgp-specific antibodies of vaccinees. In conclusion, this study provides first experimental evidence that varicella vaccines based on the Japanese Oka strain induce antibody response directed to VZV strains circulating currently in Germany.

Persistent infection with HPV 16 and 18 has been causally associated with the development of cervical cancer and its precursor lesions as well as with other carcinomas and their precursors, e.g. some vulvar and vaginal cancers. Furthermore HPV 6 and 11 are responsible for anogenital condylomata acuminata in more than 90% of cases. With the recently developed prophylactic bivalent (HPV 16 and 18) and quadrivalent (HPV 6, 11, 16 and 18) vaccines, it is possible to prevent infection of the cervical epithelium and other squamous epithelia, the development of premalignant lesions and, in the case of the quadrivalent vaccine, the development of condylomata acuminata. The following paper represents a summary of the full-text version of the German evidence-based Guidelines, including all evidence-based recommendations regarding the safety as well as the efficacy of the vaccines in preventing CIN, VIN/VaIN, genital warts and other HPV-associated lesions.

Former economic analyses have shown that universal mass vaccination of infants against varicella using a one-dose schedule is cost-saving in Germany. In July 2006, an MMRV combination vaccine has been approved in Germany which shall be given in a two-dose schedule. We re-analysed our former analysis with the EVITA model in order to prove whether our former conclusion that universal mass vaccination against varicella is cost-saving is still valid when using a two-dose schedule vaccine. Indeed we found that universal mass vaccination of infants against varicella with a two-dose vaccine is cost-saving from societal as well as from health care perspective.

This study explores the economic value of a routine varicella vaccination program for Germany. An age-structured decision analytic model was used to assess the benefits, costs and cost-effectiveness of an immunization program for a period of 30 years. Three interventions were compared with no vaccination: universal vaccination of around 15 months old healthy children, vaccination of susceptible adolescents (11-12 years of age), and the combined strategy. The analysis was conducted from both the societal perspective and the payers', i.e. sickness funds, perspective. Input data were mainly derived from a retrospective survey (analyzed were 1334 patient records) and from a seroprevalence study (n = 4602 sera). Using a coverage rate of 85% and a vaccine efficacy rate of 86% routine children vaccination could prevent around 611,000 varicella cases and over 4700 major complications per year. Average yearly cost savings for the society are 51.3 million Euro. The benefit-cost ratio (BCR) is 4.12. From the third-party payer's perspective, the BCR is 1.75 which is a consequence of significant reimbursement of parent's lost earnings by German sickness funds. The adolescent vaccination strategy has a favorable BCR ratio of 8.44 from the societal perspective, but clearly inferior medical effects. The combined vaccination strategy showed similar results as the children strategy. Routine childhood varicella vaccination appears to be a highly efficient strategy to reduce the burden of varicella and results in significant savings for both the society and the payers.

The present study was conducted to generate data on the epidemiology of varicella-zoster virus (VZV) infections in Germany as a basis for health economic evaluations of varicella vaccination strategies. The survey was designed as a cross-sectional, age-stratified study of the VZV seroprevalence in the German population. The status of immunity of 4602 individuals a aged 0 to >70 years was investigated by means of an indirect enzyme immunoassay and the fluorescent antibody to membrane assay. After waning of maternal antibodies over the period of 6-9 months seropositivity rates remained low by the end of the 1st year of life. By the age of 4-5 years 62.5% (95% CI; 56.0-68.5) of the pre-school children had already been infected with VZV and at the age of 10-11 years 94.2% (95% CI; 91.0-96.0) of children were positive for anti-VZV antibodies. Among the age-group of >40 years old, only few individuals were susceptible for VZV. The median antibody levels to VZV did not significantly decline with increasing age. In comparison with figures of previous studies the age-specific seroprevalence data presented here do not provide evidence for an upward shift in the age distribution of varicella in Germany. Since the majority of VZV infections occurs during the early childhood, the best option to reduce the circulation of wild-type VZV in the population would be the immunization of young children.

Background Nine randomized controlled clinical trials, including approximately 26,000 children aged 6 months to 17 years, have evaluated the efficacy of live attenuated influenza vaccine (LAIV) against culture-confirmed influenza illness compared with placebo or trivalent inactivated influenza vaccine (TIV). The objective of the current analysis was to integrate available LAIV efficacy data in children aged 2–17 years, the group for whom LAIV is approved for use. Methods A meta-analysis was conducted using all available randomized controlled trials and a fixed-effects model. Cases caused by drifted influenza B were analyzed as originally classified and with all antigenic variants classified as dissimilar. Results Five placebo-controlled trials (4 were 2-season trials) and 3 single-season TIV-controlled trials were analyzed. Compared with placebo, year 1 efficacy of 2 doses of LAIV was 83% (95% CI: 78, 87) against antigenically similar strains; efficacy was 87% (95% CI: 78, 93), 86% (95% CI: 79, 91), and 76% (95% CI: 63, 84) for A/H1N1, A/H3N2, and B, respectively. Classifying B variants as dissimilar, efficacy against all similar strains was 87% (95% CI: 83, 91) and 93% (95% CI: 83, 97) against similar B strains. Year 2 efficacy was 87% (95% CI: 82, 91) against similar strains. Compared with TIV, LAIV recipients experienced 44% (95% CI: 28, 56) and 48% (95% CI: 38, 57) fewer cases of influenza illness caused by similar strains and all strains, respectively. LAIV efficacy estimates for children from Europe, the United States, and Middle East were robust and were similar to or higher than those for the overall population. Conclusions In children aged 2–17 years, LAIV demonstrated high efficacy after 2 doses in year 1 and revaccination in year 2, and greater efficacy compared with TIV. This meta-analysis provides precise estimates of LAIV efficacy among the approved pediatric age group.