Malaria is a mosquito-borne sickness caused by unicellular eukaryotic parasites of the family Plasmodium. Malaria causes most damage in developing countries, where it can be fatal. World Health Organization estimated the number of Malaria cases in 2014 to more than 200 million. Symptoms of Malaria include fever, vomiting, headache, and fatigue. The malaria parasite has an intricate lifecycle, with several different stages in the mosquito and the host. The complicated life cycle is a reason why development of a vaccine is difficult.
A new study published in PNAS investigated the promising Malaria-vaccine candidate RTS,S (no, it is not a typo). RTS,S induces an antibody response, which is only partially protective due its inability to induce cytotoxic T cells. The efficacy of RTS,S is ~50%, which is the best we have at the moment for a malaria vaccine, but not good enough in general. 46 human individuals were enrolled in the study, these were then split into two groups that were given two different types of RTS,S. Both types had similar efficacy, although their immunogenicity signatures were not identical. Thus, the study highlights protective immunity through two distinct immunological mechanisms, and identifies new biomarkers that can be used to confirm protective immunity against malaria.