Beating two infections with one vaccine

From Baltimore, Md., at the Annual Conference on Vaccine Research

Identifying key similarities between related bugs could enable researchers to coax some vaccines to do double duty.

Immunity to one virus sometimes confers protection against a related microbe. Such cross-protection is the case with cowpox and smallpox, and a vaccine currently in use for Japanese encephalitis protects some animals against the closely related West Nile virus.