Toward a General Flu Vaccination Current seasonal influenza virus vaccines are targeted against specific viral strains and do not provide broad, durable protection. Seasonal influenza vaccines induce protective antibody responses against regions of viral hemagglutinin (HA) that rapidly mutate so that very soon, the virus becomes resistant to vaccination. Conserved regions of HA also exist, and a major goal of influenza vaccine development is to design a vaccine that elicits antibodies against the conserved regions so that protection against a wide range of viral strains is achieved. Wei et al. (p. 1060 , published online 15 July; see the Perspective by Doms ) show that a combined HA DNA prime, followed by boosting with a seasonal vaccine, elicits broadly cross-reactive neutralizing antibody responses in mice, ferrets, and nonhuman primates, which were protective in mice and ferrets against heterologous influenza challenge. The neutralizing antibodies were directed against the conserved HA stem region, which indicates the possibility that a more broadly protective vaccine against influenza could be developed.

Induction of Broadly Neutralizing H1N1 Influenza Antibodies by Vaccination