Malaria

Malaria kills over a million people a year and is second only to tuberculosis in its impact on world health.

The parasitic disease is present in 90 countries and infects one in 10 of the world's population - mainly people living in Africa, India, Brazil, Sri Lanka, Vietnam, Colombia and the Solomon Islands. There are four main types of malaria, all spread via mosquitoes.

Ninety per cent of all malaria cases are in sub-Saharan Africa where it is the main cause of death and a major threat to child health. Worldwide, a child dies of malaria every 30 seconds. Pregnant women are also particularly vulnerable to the disease, which is curable if diagnosed early.

The economic impact of the disease is immense, causing many lost days of work and loss of tourism and investment.

What are the symptoms?

Most people survive a bout of malaria after a 10-20 day illness, but it is important to spot the symptoms early. The first is high fever, followed a few hours later by chills. Two to four days later, this cycle is repeated.

The most serious forms of the disease can affect the kidneys and brain and can cause anaemia, coma and death.

Why has malaria increased?

After years spent bringing the disease under control, the number of people dying from malaria is now higher than it was 30 years ago and has spread to new countries.

Although it is mainly a disease of tropical and sub-tropical countries, malaria has been identified in eastern European countries such as Russia and Turkey and recently a handful of cases were diagnosed in the US.

The increase in cases is due to a number of factors:

• the disease is becoming resistant to traditional treatments. In some areas of Asia, none of the major drugs is effective in fighting malaria.
• mosquitoes are developing resistance to the main insecticides which have been used to control the spread of the disease.
• political and social upheaval has led to large numbers of people moving into new areas where disease is spread more easily.
• changes to the environment, caused by road-building, mining and irrigation projects, have created a good breeding ground for malaria.
• In many countries, budget restraints have led to malaria control programmes being cut back or abandoned.

How can malaria be contained?

The amount spent on research into malaria was around $323 million in 2004. The main thrust of research is towards developing a cheap vaccine.

None has yet been developed which is proven to work for humans outside laboratory conditions. But scientists have discovered vaccines that work on a range of animals.

The spread of the disease can be reduced by cutting down the mosquito population, for example by filling ditches where mosquitoes breed.

Early diagnosis can lead to successful treatment so education in spotting the symptoms of malaria is important. The spread of the disease can also be tracked and preparations made.

Bednets coated in insecticide have also reduced the incidence of the disease by up to 35%, according to the World Health Organisation.

RELATED INTERNET LINKS
World Health Organisation factsheet
Malaria Foundation International
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