150 Systematic Review Of The Protective Efficacy And Safety Of Hepatitis A Vaccines

Irving G, Holden J
United Kingdom
Aim: In many part of the world hepatitis A represents a significant cause of morbidity and socio-economic loss. Whilst hepatitis A vaccines have the potential to prevent disease, the degree of protection afforded against clinical endpoints and within different populations remains uncertain. The aim of this review was to evaluate the protective efficacy and safety of hepatitis A vaccination. Method: The Cochrane Hepato-Biliary Group control trials register, Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Science Citation Index Expanded and China National Knowledge Infrastructure were searched up to September 2010. Randomised control trials comparing HAV vaccine with placebo, control vaccines or no intervention were selected.
Results: 18 Randomised control trials including 1,450,415 participants met the inclusion criteria. Meta-analysis demonstrated that despite the included trials being of variable methodological quality there is convincing evidence that compared to placebo, other vaccines or no vaccination both inactivated and live attenuated HAV vaccines has good clinical protective efficacy (random effects RR = 0.09 95% CI [0.05 - 0.16], fixed effects RR = 0.08 95% CI [0.06 - 0.11]). The review also found that inactive HAV vaccine results in the significant production of seroprotective anti-HAV Ig-G and a comparable risk of adverse events. There was insufficient data to draw conclusions on seroprotection and adverse events for the live attenuated HAV vaccines.
Conclusion: This is the first systematic review conducted under Cochrane methodology that explores the clinical protective efficacy of inactivated and live attenuated HAV vaccines. Clinical protective efficacy is an important outcome to consider as it provides direct evidence of the beneficial effect of the HAV vaccine. The findings of this review have important implications for primary care including current policy surrounding HAV vaccination.
Systematic review of the protective efficacy and safety of hepatitis A vaccines