[Development of Medicines for Infectious Diseases -Malaria]

In developed countries, it is said that "threats of infectious diseases are already thought as things of the past". However, as you can see in the case of Ebola hemorrhagic fever that occurred in West Africa, this is a big mistake. Among infectious diseases, only smallpox has been successfully eradicated worldwide. In addition to the three major infectious diseases of HIV/AIDS, tuberculosis, and malaria, there is another group called emerging and reemerging infectious diseases. Recently, neglected tropical diseases (NTDs) have been listed as threats by the WHO, as have drug-resistant bacteria. The spread of these pathogens is increasing due to an increase in global travel. Malaria and more than half of the NTDs are parasitic diseases, such as trypanosomiasis and soil-borne helminthiasis. These are caused by parasites, with eukaryotes similar to their host mammals. In the case of these NTDs, protective immune responses induced by differences between a pathogen and host do not work well, and there is no vaccine against parasites. As for drugs developed to treat these diseases, because the properties of enzymes and target receptors are very similar, and effective drugs simultaneously show efficacy against both the disease and the host, severe side effects often occur. Therefore, the search for targets specifically present in parasites, and screening for drugs that inhibit their physiological functions, is extremely important. Here, as an example of the development of antiparasitic drugs, I will introduce a study on malaria.