Causes and Treatment of Herpes simplex Virus Recurrences Public Deposited

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  • March 22, 2019
  • Ludema, Christina
    • Affiliation: Gillings School of Global Public Health, Department of Epidemiology
  • Trials have demonstrated that prophylactic acyclovir treatment reduces the cumulative risk of first herpes simplex virus (HSV) recurrence after randomization, and studies have suggested that ultraviolet (UV) exposure may increase the risk of HSV recurrence. We estimated the effect of acyclovir on cumulative risk of multiple recurrences and time outdoors on risk of ocular HSV recurrences. These goals were accomplished using the Herpetic Eye Disease study, a 12-month placebo-controlled randomized trial of twice-daily oral acyclovir to prevent ocular HSV recurrence. Of the trial's 703 participants, 241 (34%) participants who started weekly report completion within 30 days of randomization were included in a nested study of orofacial herpetic recurrences. The estimated cumulative risk of non-ocular recurrence in the placebo and acyclovir groups after 180 days was 27% and 12% for first recurrences, and 11% and 3% for second recurrences, yielding risk differences of 15% (95% confidence interval (CI): 4, 26) and 8% (95% CI: 0, 15), respectively (homogeneity P value = 0.15). The unadjusted hazard ratios estimates for first and second recurrences were 0.51 (95% CI: 0.28, 0.92) and 0.55 (95% CI: 0.29, 1.03), respectively (homogeneity P value = 0.82); adjusted results were similar. Acyclovir was observed to have a smaller absolute effect and a similar relative effect on second as compared to first non-ocular HSV recurrence. A total of 308 participants were included in a nested observational study that included reports of time spent outdoors. We matched weekly UV index values from the National Oceanic and Atmospheric Administration to each participant and used marginal structural Cox models to account for confounding due to time-varying psychological stress and contact lens use and selection bias from drop-out. The weighted hazard ratios comparing those with 8+ hours of time outdoors to those with less exposure were 0.84 (95% CI: 0.27, 2.63) and 3.10 (95% CI: 1.14, 8.48), for weeks with a UV index below 4, and 4+, respectively (ratio of hazard ratios: 3.68, 95% CI: 0.43, 31.4). Though imprecise, when UV index was higher (i.e. 4+), eight or more hours per week spent outdoors was associated with increased risk of ocular HSV recurrences.
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  • In Copyright
  • Cole, Stephen
  • Doctor of Philosophy
Degree granting institution
  • University of North Carolina at Chapel Hill
Graduation year
  • 2013

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