The authors use a mouse model to show that ongoing blood stage infections, when above a minimum threshold, are able to impair the reproduction of other malaria parasites in the liver, preventing them from developing into blood stage parasites. The research shows the parasites that are in the blood are able to stimulate the production of the iron regulatory hormone hepcidin, reducing the level of iron in the liver, and it is this that inhibits the liver-stage infection. The letter goes on to discuss how this research may have implications for the global efforts to reduce malaria transmission in addition to the evaluation of iron supplementation programs present in malaria-endemic areas.
Portugal et al. Host-mediated regulation of superinfection in malaria. Nat Med. 2011 Jun;17(6):732-7. doi: 10.1038/nm.2368. Epub 2011 May 15.