Malaria is the number one killer of children under five years of age in Papua New Guinea (PNG). Pregnant mothers also are a high risk population when it come to malaria. It is now well established in PNG that the malaria parasite is resistant to chloroquine. As a result other anti-malaria drugs have been introduced. Quinine is still reserved as a last weapon. The resistant pattern is not unique to PNG. Resistance to chloroquine has been reported in Africa, Asia and South America where malaria is endemic. As a result the world medical community is intensively screening possible malaria vaccines.
I just returned from the 41st US-Japan Joint Conference on Parasitic Diseases which was held at the Institute of Medical Sciences, University of Tokyo. And screening for potential malaria vaccine candidates was one of the most important talked about topics. Some vaccine trials are ongoing in Africa. Some years back, I remember reading about a vaccine trail completed in Maprik by PNGIMR with collaborators in USA and Australia. That project is still going on.
Developing a vaccine is a very long process. And the trial itself has to go through many stages before it can be declared safe and effective to be further developed for mass production. It requires A LOT OF FUNDING. With malaria it seems we still have to know more about the parasite itself which will help us to identify potential vaccine targets.
So will PNG see a malaria vaccine soon? My impression is not in the foreseeable future. Our best option right now remains controlling the vector – Anopheles mosquito. And treating acute infections with available drugs. When the WHO banned the spraying of DDT which was used for killing mosquitoes in the 196Os-1970s, a new effective insecticide has not come into the market. In 2006, 30 years after DDT was banned, WHO lifted the ban so that malaria endemic countries can use it again against the malaria vector. This means probably from the 1960s up until today an alternative was not developed. Despite many studies into plant-derived potential insecticides, an effective insecticide against the malaria vector is yet to be developed (apart from DDT). The current emphasis on integrated-management of insecticides, meaning, an insecticide used nowadays must be environmentally friendly and do minimal damage to non-target organisms, has limited the development of synthetic insecticides.
In the mean time treating acute cases and interrupting the transmission of malaria by mosquitoes remains the only way in which the burden of malaria can be reduced. In PNG I think apart from the use of bed nets in the villages to prevent mosquito bites, more should done to reduce or control mosquito breeding sites and controling the acquatic stages of the mosquito (larvae and pupae).