Duration of Protection from Malaria Vaccine

Continued follow-up of children who received malaria vaccine in an earlier study shows that partial protection lasts at least 18 months.

In 2003–2004, investigators conducted a randomized, controlled, double-blind trial in Mozambique to test the malaria vaccine candidate RTS,S/ASO2A among children (see Journal Watch Infectious Diseases Nov 5 2004). The subunit pre-erythrocytic vaccine is based on Plasmodium falciparum circumsporozoite surface antigen, fused to hepatitis B antigen. The vaccine’s efficacy, although only 27% for all clinical episodes and 58% for severe malaria during the first 6 months after immunization, was encouraging. Now, the investigators (supported by the Malaria Vaccine Initiative and industry) have conducted single-blind follow-up of the participants for an additional 12 months.

The primary endpoint of the study was clinical malaria (fever and P. falcip…

Reviewing Author

Mary E. Wilson, MD