A 'miracle' HIV shot, surprising shingles vaccine benefit and health-threatening wildfires: What to know about this week's health news Yahoo LifeDoctor behind trial of HIV prevention drug recounts breakthrough moment The GuardianTwice-a-year shot offers 100 percent HIV protection, study finds The Washington PostTwice-Yearly Shot Offers 100% HIV Protection, Study Finds HealthlineBeginning of end of HIV epidemic?