The shingles vaccine, known as Shingrix, has been found to have a certain level of efficacy, although the exact duration of its effectiveness is still being considered. Some studies have reported benefits of the vaccine, including a potential link to lower dementia risk, while others have noted a temporary increase in shingles cases after the first dose. The vaccine's dosage schedule and potential side effects are also being examined, with guidance available for immunocompromised adults and those who may have missed a second dose.