Effectiveness of rimantadine prophylaxis of children within families
R. D. Clover, S. A. Crawford, T. D. Abell, C. N. Ramsey Jr, W. P. Glezen and R. B. Couch
With recent studies suggesting that children are the main introducers of
influenza infections into families, we conducted a placebo-controlled,
double-blind, randomized trial to study the prophylactic effectiveness of
rimantadine hydrochloride in children on the transmission of influenza A
infections within families. One hundred forty-five volunteers from 35
families completed this study during a naturally occurring outbreak of
influenza A (H1N1) infection. Influenza infections, defined as a positive
viral throat culture or a fourfold increase in antibody titer, occurred in
31.7% of children in the placebo group and 2.9% of children in the
rimantadine group. Clinical illness with laboratory evidence of influenza
infection occurred in 17.0% of children in the placebo group and 0% of
children in the rimantadine group. Rimantadine was well tolerated by the
children, with no significant difference in reported side effects between
the placebo and rimantadine groups. Influenza A infection occurred in 19.0%
of adults whose children were receiving a placebo and 8.8% of adults whose
children were receiving rimantadine. On the basis of our study, rimantadine
prophylaxis of children appears to be an effective method to prevent
influenza A infection in children. Additional studies are needed to
demonstrate the effects of rimantadine prophylaxis of children on the
incidence of influenza A infection in their parents.