WHO Protocols
Please see the WHO website for current publications pertaining to antimalarial resistance and monitoring:
http://www.who.int/drugresistance/malaria/en/
All tools and publications on this page are independently published on the World Health Organization website and are courtesy of WHO.
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See the newly-published Methods for Surveillance of Antimalarial Drug Efficacy.
WHO, 2009.
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Antimalarial drug resistance is a major public health problem which hinders the control of malaria. The WHO publication, Drug resistance in malaria, describes the state of knowledge about this problem and outlines the current thinking regarding strategies to limit the advent, spread and intensification of drug-resistant malaria.
- Country support
- Drug resistance in malaria
With the rapid spread of antimalarial drug resistance over the last few decades, the need for monitoring has increased. Tracking of evolving resistance patterns is essential for proper management of clinical cases and to determine thresholds for revising national malaria treatment policies. Available testing procedures include therapeutic efficacy testing (also known as in vivo testing), in vitro sensitivity assay, and studies of gene mutations or gene amplification associated with parasite resistance.
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Tools for monitoring
1. Therapeutic efficacy tests
In 1996, WHO had developed a protocol for assessing the therapeutic efficacy of antimalarial drugs for the treatment of falciparum malaria in intense transmission areas.
During the WHO consultation on antimalarial drug resistance held in December 2001, this protocol has been updated. During the same meeting, a protocol for assessing the therapeutic efficacy of antimalarial drugs for the treatment of falciparum malaria in low to moderate transmission areas as well as a protocol for assessing the efficacy of chloroquine for the treatment of Plasmodium vivax have been discussed.
- Assessment of therapeutic efficacy of antimalarial drugs for uncomplicated falciparum malaria in areas with intense transmission [pdf 520kb]
- Antimalarial drug resistance protocol
Other tools can be used for research as well as for early warning systems.
2. In vitro tests
The most commonly used methods for the antimalarial in vitro testing are the in vitro micro-test Mark III the isotopic test and drug sensitivity assay based on the measurement of HRP2/or pLDH/ in an enzyme-linked immunosorbent assay (ELISA). In vitro pre-dosed plates for the assessment of parasite in vitro susceptibility to antimalarial drugs can be purchased through the Vector Control Research Unit, Universiti Sains Malaysia, Penang, Malaysia under the auspices of WHO.
- In vitro micro test [pdf 81kb]
- In vitro pre-dosed plates [pdf 16kb]
3. Molecular markers
Molecular markers of P. falciparum resistance are available for only a few drugs (chloroquine, pyrimethamine, cycloguanil, sulfadoxine, atovaquone), while for others they are not yet determined. WHO in collaboration with the WHO Regional Offices is assisting countries in training the medical staff on standardized protocols and in analysing the data. Standardized data entry programmes for the therapeutic efficacy test, for the WHO in vitro test and Probit calculus sheets are available.
- Data entry for in vitro test [xls 49kb]
- Probit calculus sheet [xls 244kb]
