What data are available concerning transmission of varicella vaccine virus to contacts?
Available data suggest that the risk of vaccine virus transmission from healthy vaccinees is very low and occurs only if the vaccinee has a rash. With the currently licensed vaccine, there have been 3 documented cases of transmission from healthy vaccinated children. The risk for transmission from vaccinees who are immunocompromised is higher. • Will post-exposure use of the vaccine prevent or modify varicella? Yes, the vaccine may prevent or modify illness when administered within 3 to 5 days after exposure. The ACIP now recommends vaccination of susceptible persons who are eligible for vaccination as soon as possible after exposure–ideally within 3 days but possibly up to 5 days of an exposure–to prevent illness or modify disease severity. If a person has already been infected, and the vaccine is given soon enough, disease may be modified or prevented. If the person was infected >5 days prior to vaccination, there is unlikely to be any benefit from vaccination but vaccination is no
