The quality of evidence is downgraded by study limitations (unclear allocation concealment) and by imprecise results (few patients).
A Cochrane review [Abstract] 1 included 3 studies with a total of 110 children who were siblings of household contacts. Overall, 13 out of 56 vaccine recipients (23%) developed varicella compared with 42 out of 54 placebo (or no vaccine) recipients (78%). Of the vaccine recipients who developed varicella, the majority only had mild disease (with fewer than 50 skin lesions). In the three trials, most participants received post-exposure prophylaxis (PEP) within three days following exposure; too few participants were vaccinated four to five days post-exposure to ascertain the efficacy of vaccine given more than three days after exposure. No included trial reported on adverse events following immunisation.
Date of latest search: 2014-03-18
Primary/Secondary Keywords