Malaria: scientific advances may reduce the risks

Using a battery of high-tech approaches, scientists from the University of Glasgow and the Wellcome Trust Sanger Institute near Cambridge have identified the factor that the parasite must produce to begin the process of passing from human to mosquito and, therefore, completing its full life cycle. Details of the research appeared recently in the journal Nature.

This discovery opens up the way to potential new drug treatments that would prevent transmission of the disease.

Malaria is transmitted to people through the bites of mosquitoes which have themselves been infected by the Plasmodium parasites that cause the disease through a previous blood meal taken from an infected person. When a mosquito bites an infected person, a small amount of blood is taken in which contains microscopic malaria parasites. About two weeks later, when the mosquito takes its next blood meal, the progeny of these parasites mix with the mosquito's saliva and are injected into the person being bitten. The whole process of the parasite passing through the mosquito is called transmission.

The objective of the University of Glasgow/Wellcome Trust Sanger Institute team has been to identify the way the parasite changes to allow transmission to be switched on and to take place.

The discovery of how this process works means this "transmission switch" could be disabled in future through the development of new drugs. However, any drug treatment developed as a result of this research is likely to be what scientists describe as an "altruistic intervention". The drug would be taken by adults who were already infected by malaria but had developed resistance to the disease; the drug would block the "transmission switch", thus preventing re-infection or infection to, for instance, their children.  It is anticipated that many parents would agree to take such a drug if it meant offering greater protection to their children.

According to the World Health Organisation, there were 26 million reported cases of malaria in 2011. Sub Saharan Africa remains the main stronghold of the parasite with Madagascar, Somalia, Burundi and Liberia accounting for the highest number of reported cases. These territories are also important centres for aid and NGO workers, meaning many expatriate workers are running a real risk of exposure to the disease.

Although mild malaria is now relatively easy to treat, as with most diseases, the effectiveness of the medication is enhanced considerably if an early diagnosis and treatment is possible.

In the event that a patient contracts severe malaria, the treatment is more complex, as the disease has to be carefully monitored for complication. The main difference between severe and mild malaria is related to the number of red blood cells which are infected, with severe cases usually resulting from delays to diagnosis and treatment.

For expatriates living and working in high risk malaria zones, this is important, as it is likely that local medical facilities will not be adequate to offer diagnosis and treatment, especially in the case of NGO and aid workers who may be working in remote centres of population. In such circumstances, access to international private medical insurance is essential.

Highlighting the example of two clients who have recently contracted the disease, with both requiring emergency air evacuation to access appropriate medical facilities, Debbie Purser, managing director of international health provider MediCare International comments, "Malaria is the biggest parasitic disease killer that there is in the world and there is currently no vaccine, so having fast and effective access to the right medical facilities to ensure diagnosis and treatment is essential. In particular, where NGO and other aid workers are stationed in remote parts of Africa, it is likely that evacuation to a nearby, more comprehensive international medical facility will be needed. We have recently arranged and paid for the evacuation of two clients, one from Angola and one from Sudan for just this reason. At MediCare International, the offer of emergency evacuation is a core part of our package to working expatriates of any nationality, but it is particularly important for NGO and aid workers. Whilst the costs of the drugs required to treat malaria is relatively modest, any emergency evacuation could easily run up fees of several thousand pounds, but, all such costs could be met under our policies, both on an individual or group scheme basis."

With over 30 years experience of providing worldwide healthcare insurance for the international business community and clients from 86 nationalities in 121 countries, MediCare International  - website www.medicare.co.uk - is a major provider of health insurance for expats across the world, including many working in NGOs and other voluntary organisations.