Vaccine research shows vigilance needed against evolution of more-virulent malaria

Malaria parasites evolving in vaccinated laboratory mice become more virulent, according to research at Penn State University. The mice were injected with a critical component of several candidate human malaria vaccines that now are being evaluated in clinical trials. “Our research shows immunization with this particular type of malaria vaccine can create ecological conditions that favor the evolution of parasites that cause more severe disease in unvaccinated mice,” said Andrew Read, Alumni Professor of Biological Sciences at Penn State. “We are a long way from being able to assess the likelihood of this process occurring in humans, but our research suggests the need for vigilance. It is possible that more-virulent strains of malaria might evolve if a malaria vaccine goes into widespread use,” Read said. The research, which is published in the 31 July 2012 issue of the scientific journal PLoS Biology, showed that more-virulent malaria parasites evolved in response to...