Background Varicella vaccine is now frequently administered to HIV-infected children who remain relatively healthy because it has been shown to be safe and immunogenic but its effectiveness for this population remains unknown. immunization and the development of varicella or zoster. The vaccine’s effectiveness for varicella and for zoster was calculated by subtracting from one rate-ratios for the incidence rates of varicella or zoster in vaccinated vs. unvaccinated children. Results The effectiveness of varicella vaccine for preventing varicella was 82% (95% CI: 24%-99%; p = 0.01) and for preventing zoster was 100% (95% CI 67%-100%; p<0.001). When only those receiving highly active antiretroviral therapy (HAART) were included in this analysis (to assess effectiveness of vaccine independent of the effect of HAART) the vaccine's effectiveness against zoster was 100% (95% CI: 63%-100%; p=0.001). Conclusion Varicella vaccine is usually WYE-354 highly effective in preventing both varicella and zoster in HIV-infected children. Introduction HIV-infected children may develop severe varicella and are >15 occasions WYE-354 more likely than the general populace to develop herpes zoster (HZ) which is usually often severe . Live attenuated varicella vaccine is usually safe immunogenic and protective against varicella-zoster (VZV) contamination in both healthy and certain immunocompromised children . Based on clinical trials 2 doses of varicella vaccine 2 months apart were recommended in 1999 for relatively WYE-354 healthy HIV-infected children with CD4 cell counts ≥ 25% . Later children with CD4 counts of ≥ 15% were safely vaccinated . Although the vaccine is usually widely used there is no published information on its effectiveness in these children [5 6 Therefore we assessed the effectiveness of varicella vaccine in preventing varicella and HZ in this populace. Methods We conducted a longitudinal cohort study with clinical data collected from 2 models of the Pediatric AIDS Clinical Trials Group (PACTG): Columbia University-New York Presbyterian Hospital and St. Jude Children’s Research Hospital. This study was approved by both IRBs. The medical records of 164 perinatally HIV-infected children between 1989 and 2007 determining whether and when they had received varicella vaccine developed varicella and/or developed HZ. All perinatally HIV-infected children were included except for those WYE-354 who developed varicella before one year of age because varicella vaccine is not given before then. Vaccine was offered to children based on the recommendations of the Centers for Disease Control at the time. Varicella was defined as an illness with a generalized pruritic vesicular rash with fever diagnosed Rabbit Polyclonal to DQX1. by a clinician. HZ was an illness with a unilateral vesicular rash in a dermatomal distribution without another identifiable cause. Laboratory confirmation of VZV usually was not obtained. Immunized children had at least 1 dose of live attenuated varicella vaccine. Highly active antiretroviral therapy (HAART) was defined as receipt of ≥ 3 antiretroviral brokers two non-nucleoside reverse transcriptase inhibitors and either a protease inhibitor or a nucleoside reverse transcriptase inhibitor. HZ that occurred within 6-8 weeks after initiation of HAART was considered to be a possible instance of the immune reconstitution inflammatory syndrome (IRIS). The statistical significance of differences of baseline characteristics of groups being compared was assessed with chi-squared assessments for categorical variables and with t-tests for continuous variables. All follow-up occasions were calculated in person-years (P-Y). Rate ratios their associated 95% confidence intervals and their statistical significance (two-tailed < 0.001) (Table 2). Table 2 Incidence rates of varicella and HZ in HIV-infected children who were either vaccinated against varicella or had natural contamination Vaccinated children Two of 72 (3%) developed breakthrough varicella 3.9 and 4.7 years after last immunization respectively; one child received 1 dose of vaccine and the other received 2 doses. . The incidence of varicella was 2/296 P-Y (6.8/1000 P-Y; 95% CI: 0.82-24/1000) (Table 2). The vaccine’s effectiveness against varicella (6.8/1000 P-Y in the vaccinees vs. 36.8/1000 P-Y in the.