INTRODUCTION Malaria remains one of the most serious tropical diseases in many parts of the world. The malaria situation is deteriorating in many areas
impairing the prevention and treatment of malaria, despite major control campaigns. Resistance of the malaria parasite to antimalarial drugs is increasing and becoming more widespread.
1 The incidence of travel-related malaria is increasing, especially in visitors to endemic African countries.In South Africa fluctuations in malaria incidence
have been shown to be associated with climatic conditions (temperature and rainfall), as well as the influx of migrants from neighbouring countries. In the past, malaria parasites in
South Africa were regarded as sensitive to chloroquine. Studies made since 1988, in vitro2,3 and in vivo 4,5
showed an appearance and increase in resistance to chloroquine and spreading of its distribution in the eastern parts of the country. These have necessitated continuing changes in chemoprophylaxis
6 and treatment policies for South Africa.
DISTRIBUTION OF MALARIA GLOBAL DISTRIBUTION Malaria occurs in many parts of the tropics and subtropics in North, Central and South America, Africa, Asia and Oceania (Figure 1).1
DISTRIBUTION IN SOUTH AFRICA Malaria occurs in limited areas in South Africa. The endemic malaria areas are the low altitude areas (below 1000 metres) of the Northern
Province, Mpumalanga, and the north eastern part of KwaZulu-Natal (Figure 2). Occasionally limited focal transmission may develop in the North-West and Northern Cape provinces along
the Molopo and Orange Rivers. Infections are very seldom contracted outside the malarious areas and are then possibly a consequence of the importation of infected mosquitoes by
motor or other transport. PARASITES Human malaria is caused by four species of the Plasmodium parasite namely Plasmodiumfalciparum, P. vivax, P. ovale, and P.
malariae. All these species are transmitted to human beings by the bite of an infected female mosquito of malaria- transmitting Anopheles species. Plasmodium falciparum
occurs in most malaria affected areas of the world and in most of these areas it is resistant to the antimalarial drug chloroquine. Plasmodium vivax
has a similar distribution, but is predominantly found in South America and the Middle East, while it is uncommon in sub-Saharan Africa. Plasmodium ovale and P. malariae
distribution is predominantly in Africa. The identification of the specific infective malaria species is important to ensure appropriate treatment. In South Africa about 90-95% of the locally contracted cases are due to
P. falciparum. Sometimes reference is made to "new strains of malaria". This means that strains of drug-resistant P. falciparum
are present in an area. The degree and extent of chloroquine resistance in South Africa is currently not known and warrants epidemiological study. The guidelines are endorsed by the Medical Association of South Africa. |
