|Management of Uncomplicated Malaria and the Use of Antimalarial Drugs for Protection of Travellers (WHO - OMS, 1995, 108 p.)|
Early diagnosis and prompt treatment are fundamental to malaria control and need to be available wherever malaria occurs. Correct treatment of malarial disease will shorten its duration and largely prevent the development of complications and death.
The worsening problems of drug resistance in many parts of the world and the limited number of antimalarial drugs available have led to increasing difficulties for the provision of adequate disease management. It is now recognized that most endemic countries will have to face the unavoidability of some resistance to the antimalarial drugs used to treat uncomplicated malaria. This highlights the importance of appropriate diagnosis to identify early treatment failures and target alternative drugs to such cases.
Among the countries where falciparum malaria is endemic, only those of Central America and Egypt (Fayoum Governorate) have not recorded resistance of Plasmodium falciparum to chloroquine. Chloroquine resistance of various levels is now common in practically all endemic countries in Africa and, especially in eastern Africa, poses increasing problems for the provision of adequate treatment. In western and middle South Asia, as well as in Malaysia, the Philippines and Oceania, levels of chloroquine resistance are variable. Resistance to the main alternative to chloroquine, sulfadoxine/pyrimethamine, is wide-spread in South-East Asia and South America but is focal in other parts of the world (1). There are recent reports of decreasing efficacy of the combination in certain parts of eastern and southern Africa where it is increasingly being used.
Mefloquine resistance is now common in Thailand. More than 50% of falciparum infections in certain areas bordering Cambodia and Myanmar are resistant to the drug. Reduced susceptibility to mefloquine has been detected in vitro in Africa, but has not been reflected in clinical management. It has not been reported from the Americas. The sensitivity to quinine is also diminishing in several countries of South-East Asia as well as in Brazil, where quinine plus tetracycline has been used as the standard treatment for uncomplicated malaria. Consequently, artemisinin and its derivatives are now increasingly deployed for first-line treatment in certain of these areas (2).
Resistance of vivax infections to chloroquine, first documented in 1989 in Papua New Guinea, has now been confirmed in Indonesia, Myanmar and Vanuatu. In some localized foci, 20-30% of patients infected with vivax malaria have shown recurrences of parasites 1-3 weeks after a course of 25 mg chloroquine/kg (2).
Each country needs an antimalarial drug policy in order to provide effectively early diagnosis and prompt treatment. Such policies need to take into consideration:
- the epidemiological factors that affect the distribution of the parasite and its pattern of drug resistance;
- the characteristics of the health services including those in the private sector;
- the levels of health care at which different drugs will be available;
- the risks and benefits of different drug regimens, compliance with them and their cost; and
- logistics and cost of drug delivery i.e. affordability.
As a general principle, a policy should aim at reducing malaria mortality and morbidity and the development of drug resistance, while keeping within the limits of each countrys budgetary and staffing possibilities. All health care providers, whether public or private, should be fully cognizant with national policies and their rationale. Guidelines addressing the broad aspects for the development of such policies have been developed (2).
This document complements these Guidelines, with respect to the management of uncomplicated malaria, by:
- evaluating current approaches for malaria diagnosis;
- providing guidelines on the principles of therapy and ancillary treatment;
- evaluating the roles of currently used antimalarial drugs; and
- providing recommendations and regimens for the use of antimalarial drugs, with special reference to specific target groups.
In addition, the use of antimalarial drugs currently recommended for chemoprophylaxis is evaluated with special reference to age and population groups, toxicity and interaction with other drugs.