Barbara E. Menzies

Long-Term Persistence of Zoster Vaccine Efficacy

BACKGROUND The Shingles Prevention Study (SPS) demonstrated zoster vaccine efficacy through 4 years postvaccination. A Short-Term Persistence Substudy (STPS) demonstrated persistence of vaccine efficacy for at least 5 years. A Long-Term Persistence Substudy (LTPS) was undertaken to further assess vaccine efficacy in SPS vaccine recipients followed for up to 11 years postvaccination. Study outcomes were assessed for the entire LTPS period and for each year from 7 to 11 years postvaccination. METHODS Surveillance, case determination, and follow-up were comparable to those in SPS and STPS. Because SPS placebo recipients were offered zoster vaccine before the LTPS began, there were no unvaccinated controls. Instead, SPS and STPS placebo results were used to model reference placebo groups. RESULTS The LTPS enrolled 6867 SPS vaccine recipients. Compared to SPS, estimated vaccine efficacy in LTPS decreased from 61.1% to 37.3% for the herpes zoster (HZ) burden of illness (BOI), from 66.5% to 35.4% for incidence of postherpetic neuralgia, and from 51.3% to 21.1% for incidence of HZ, and declined for all 3 outcome measures from 7 through 11 years postvaccination. Vaccine efficacy for the HZ BOI was significantly greater than zero through year 10 postvaccination, whereas vaccine efficacy for incidence of HZ was significantly greater than zero only through year 8. CONCLUSIONS Estimates of vaccine efficacy decreased over time in the LTPS population compared with modeled control estimates. Statistically significant vaccine efficacy for HZ BOI persisted into year 10 postvaccination, whereas statistically significant vaccine efficacy for incidence of HZ persisted only through year 8.

Safety of Zoster Vaccine in Elderly Adults Following Documented Herpes Zoster

BACKGROUND After completion of the Shingles Prevention Study (SPS; Department of Veterans Affairs Cooperative Studies Program Number 403), SPS participants who had initially received placebo were offered investigational zoster vaccine without charge. This provided an opportunity to determine the relative safety of zoster vaccine in older adults following documented herpes zoster (HZ). METHODS A total of 13 681 SPS placebo recipients who elected to receive zoster vaccine were followed for serious adverse events (SAE) for 28 days after vaccination. In contrast to the SPS, a prior episode of HZ was not a contraindication to receiving zoster vaccine. The SPS placebo recipients who received zoster vaccine included 420 who had developed documented HZ during the SPS. RESULTS The mean interval between the onset of HZ and the receipt of zoster vaccine in the 420 recipients with prior HZ was 3.61 years (median interval, 3.77 years [range, 3-85 months]); the interval was <5 years for approximately 80% of recipients. The proportion of vaccinated SPS placebo recipients with prior HZ who developed ≥ 1 SAE (0.95%) was not significantly different from that of vaccinated SPS placebo recipients with no prior history of HZ (0.66%), and the distribution of SAEs in the 2 groups was comparable. CONCLUSIONS These results demonstrate that the general safety of zoster vaccine in older persons is not altered by a recent history of documented HZ, supporting the safety aspect of the Centers for Disease Control and Prevention Advisory Committee on Immunization Practices recommendation to administer zoster vaccine to all persons ≥ 60 years of age with no contraindications, regardless of a prior history of HZ.

Inhibition of Staphylococcal Wound Infection and Potentiation of Antibiotic Prophylaxis by a Recombinant Fragment of the Fibronectin-Binding Protein of Staphylococcus aureus

Adherence of Staphylococcus aureus to host tissues is a critical step for colonization and initiation of infection. The fibronectin-binding proteins (FnBPs) of S. aureus have been implicated in adherence and internalization in nonprofessional phagocytes. A recombinant fragment of the fibronectin-binding domains (rFnBF) that potently inhibits S. aureus entry into host cells was generated. To test the hypothesis that rFnBF may attenuate the establishment of infection, the ability of intermuscularly administered rFnBF to prevent abscess formation was determined in a guinea pig model of wound infection. rFnBF exhibited dose-dependent inhibition of abscess formation and, at a 100-microg dose, raised the median infective dose approximately 170-fold, compared with the control. In addition, rFnBF potentiated the benefit of prophylaxis with cefazolin. Thus, exogenous administration of the fibronectin-binding domain of FnBP reduces the risk of staphylococcal abscess formation and should be investigated further as a novel agent for prevention of wound infection.