Among over 3,300 Chinese adults over 50 who got the shingles vaccine, only about 2 in 1,000 had a severe adverse event that prevented normal daily activities within a month, and only two of those were thought to be possibly linked to the vaccine.
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
A systematic review and meta-analysis of RCTs and cohort studies could determine whether RZV increases the relative risk of grade 3 medically attended adverse events compared to placebo or no vaccination in adults ≥50.
A systematic review and meta-analysis pooling individual participant data from at least 15 RCTs and prospective cohort studies involving 100,000+ adults ≥50, comparing incidence of grade 3 MAEs within 30 days of RZV versus control, using standardized MedDRA grading and blinded adjudication.
A randomized controlled trial could determine whether the incidence of grade 3 medically attended adverse events is significantly higher after RZV vaccination than after placebo injection in adults ≥50.
A double-blind, placebo-controlled trial of 20,000 adults aged 50–85, randomized 1:1 to receive RZV or saline placebo, with active surveillance for medically attended events over 30 days, using standardized criteria for grade 3 severity and independent, blinded adjudication.
A prospective cohort study with an unvaccinated control group could estimate the relative risk of grade 3 medically attended adverse events following RZV vaccination in a real-world Chinese population.
A prospective cohort study of 50,000 Chinese adults aged 50–85, with 25,000 receiving RZV and 25,000 not vaccinated, followed for 30 days with active surveillance for medically attended events, using standardized severity grading and adjusting for age and comorbidities.
A case-control study could identify whether grade 3 medically attended adverse events occur more frequently in individuals who received RZV compared to those who did not.
A matched case-control study of 500 Chinese adults aged 50+ diagnosed with a grade 3 medically attended adverse event within 30 days of vaccination, each matched to two controls without such an event, assessing prior RZV exposure within 60 days, with blinded exposure assessment and medical record verification.
A cross-sectional survey could estimate the prevalence of recent grade 3 medically attended adverse events among vaccinated and unvaccinated adults ≥50 in China at a single point in time.
A nationally representative survey of 20,000 Chinese adults aged 50+ asking about vaccination status and any grade 3 medically attended adverse event within the past 30 days, using validated questionnaires and medical record verification for a subset.