Malaria: Hereditary information of two rare pathogens decoded
An international team of scientists has sequenced the genomes of two rare malaria pathogens, both parasites of the plasmodium species.
An international team of scientists has sequenced the genomes of two rare malaria pathogens, both parasites of the plasmodium species. A scientist from the Bernhard Nocht Institute for Tropical Medicine and the German Center for Infection Research has also been involved. The scientific journal Nature has published the results, with which the scientists make a contribution towards improving global malaria control.
Up to now, the two rarest species of human malaria pathogens, Plasmodium malariae and Plasmodium ovale, have managed to escape the attention of researchers. In comparison to the known pathogen Plasmodium falciparum which causes severe malaria, they do not occur as frequently and do not have as severe courses of disease. However, their significance should not be underestimated, because they are responsible for approximately ten million cases of malaria per year, i.e. five percent of all cases. Their genetic decoding now makes it possible to diagnose these cases, and consequently develop suitable drugs and vaccines.
“These two plasmodium species, which have been neglected up to now, have the particular characteristic feature of remaining hidden in the host for a very long time,” explains Prof Jürgen May, scientist at the BNITM and the DZIF. A comparison of the sequences to those of known plasmodium species has now made visible the genes which could be responsible for this adaptation to the host. “If we know the genes that protect the plasmodia from the human immune system, we have advanced a great step on the path to developing specific treatment and perhaps a new vaccine,” explains co-author Oumou Maiga-Ascofare, a young scientist from Mali, who, with the support of the DZIF, strengthens malaria research at the Bernhard Nocht Institute for Tropical Medicine in Hamburg.
The international study, which was conducted under the supervision of the renowned Wellcome Trust Sanger Institute, also fills a gap in the plasmodia’s phylogenetic tree and contributes towards a better understanding of their evolution. The scientists hope to have made an important contribution to fully controlling malaria on a global scale.
Background: malaria
Malaria parasites (plasmodia) are transmitted to humans by bites from infected anopheles mosquitoes. The Plasmodium falciparum species is responsible for the majority of malaria cases worldwide and for almost all deaths. Malaria causes intermittent high fever and can lead to death if left untreated. A vaccine has not been available to date, but the DZIF is also working on this at full speed. Malaria particularly affects African populations, which account for over 80 percent of the cases. In 2015, there were 214 million new malaria cases, and almost half a million people died of the disease.