Latest overview of malaria treatment by WHO

Latest overview of malaria treatment by WHO

Malaria is an entirely preventable and treatable disease. The primary objective of treatment is to ensure the rapid and complete elimination of the Plasmodiumparasite from the patient’s blood in order to prevent progression of uncomplicated malaria to severe disease or death, and to prevent chronic infection that leads to malaria-related anaemia.

From a public health perspective, the goal of treatment is to reduce transmission of the infection to others, by reducing the infectious reservoir, and to prevent the emergence and spread of resistance to antimalarial medicines.

Importance of diagnostic testing

Patients with suspected malaria should have parasitological confirmation of diagnosis with either microscopy or rapid diagnostic test (RDT) before antimalarial treatment is started. Treatment based on clinical grounds should only be given if diagnostic testing is not immediately accessible within 2 hours of patients presenting for treatment. Prompt treatment – within 24 hours of fever onset – with an effective and safe antimalarial is necessary to prevent life-threatening complications.

Treatment of uncomplicated malaria

Treatment of P. falciparum infections

WHO recommends artemisinin-based combination therapies (ACTs) for the treatment of uncomplicated malaria caused by the P. falciparum parasite. By combining 2 active ingredients with different mechanisms of action, ACTs are the most effective antimalarial medicines available today. WHO currently recommends 5 ACTs for use against P. falciparum malaria. The choice of ACT should be based on the results of therapeutic efficacy studies against local strains of P. falciparum malaria.

ACTs are the mainstay of recommended treatment for P. falciparum malaria and, as no alternative to artemisinin derivatives is expected to enter the market for at least several years, their efficacy must be preserved. WHO recommends that national malaria control programmes regularly monitor the efficacy of antimalarial medicines in use to ensure that the chosen treatments remain efficacious.

In low transmission areas, a single low dose of primaquine should be added to the antimalarial treatment in order to reduce transmission of the infection. Testing for glucose-6-phosphate dehydrogenase (G6PD) deficiency is not required, as a single low dose of primaquine is both effective in blocking transmission and unlikely to cause serious toxicity in individuals with any of the G6PD-deficiency variants.

Oral monotherapy and artemisinin resistance

Artemisinin and its derivatives must not be used as oral monotherapy, as this promotes the development of artemisinin resistance. Moreover, fixed-dose formulations (combining 2 different active ingredients co-formulated in 1 tablet) are strongly preferred and recommended over co-blistered, co-packaged or loose tablet combinations, since they facilitate adherence to treatment and reduce the potential use of the individual components of co-blistered medicines as monotherapy.

Treatment of P. vivax infections

P. vivax infections should be treated with chloroquine in areas where this medicine remains effective. In areas where chloroquine-resistant P. vivax has been identified, infections should be treated with an ACT, preferably one in which the partner medicine has a long half-life.

In order to prevent relapses, primaquine should be added to the treatment; dose and frequency of the administration should be guided by the patient’s glucose-6-phosphate dehydrogenase (G6PD) enzyme activity.

Treatment of severe malaria

Severe malaria should be treated with injectable artesunate (intramuscular or intravenous) for at least 24 hours and followed by a complete 3-day course of an ACT once the patient can tolerate oral medicines. When injectable treatment cannot be given, children under 6 years of age with severe malaria should receive a pre-referral treatment with rectal artesunate before being referred immediately to a health care facility where the full level of care can be provided.

In view of the latest development of resistance, it is essential that neither artemisinin-based injectables nor artesunate suppositories be used as monotherapies – the initial treatment of severe malaria with these medicines needs to be completed with a 3-day course of an ACT.

Expansion of access to ACTs

In recent years, access to ACTs has expanded substantially. By the end of 2014, ACTs had been adopted as first-line treatment policy in 81 countries. In 2013 and 2014, respectively 392 million and 337 million ACT treatment courses were delivered to both the public and the private sectors in endemic countries. Expanding case management at the community level is accelerating progress towards the goal of universal access to diagnostic testing and effective antimalarial treatment.