with support from Alix Beith and Scott Kniaz.
I am finding it hard to choose a side on the recent malaria treatment policy debate. It is clear that current anti-malarial treatment policy -- which dictates that, in high-transmission settings, children under five that have a fever are given anti-malarials -- certainly not optimal. Children with fevers not caused by malaria may suffer side-effects from taking unnecessary anti-malarial drugs and are also not being treated for what ails them. Additionally, excessive use of anti-malarials is a driver of the emergence of drug-resistant strains of the malaria parasite, which can then be transmitted to the larger community.
Malaria drug resistance is a world-wide problem. All over the globe, once extremely effective drugs like chloroquine can no longer get the job done, with resistance levels as high as 80% in Latin America. In fact, the deadliest malaria parasite, P. falciparum, has shown resistance to all treatments except artemisinin. However, there are worrying signs that tolerance to artemisinin may be developing in some areas, specifically along the Thai-Cambodian border. Once (and it is "once", not if) artemisinin-resistance emerges and spreads, we will have no silver -- or even bronze -- bullets (at least for now) for the fight against malaria.
So; back to the current debate. In the January 6, 2009 edition of PLoS Medicine, Genton et al. argue that it's time for a policy change. They argue that presumptive treatment in high transmission areas is not as safe as it was 20 years ago, due to evidence of decreased malaria transmission in sub-Saharan Africa and an overall decline in the proportion of fevers due to malaria. They recommend all febrile patients be diagnosed first, before providing treatment, citing the increasing availability of reliable, easy-to-use, inexpensive rapid diagnostic tests (RDTs) for malaria as additional support for the needed policy change. Past research has shown that, even where RDTs are available and used, providers may give a feverish patient an anti-malarial even when the test result is negative. In response, Genton et al. cite evidence that provider behavior change can come about through proper provider training and increased provider trust in the RDTs effectiveness gained through use of RDTs.
In the same edition of the online Journal, English et al argue against a change in policy, voicing two key concerns: first, that evidence of RDT effectiveness is not robust, and second, that health systems may not currently have the capacity to implement such a policy. If either of these is true, a change in treatment policy could result in increased mortality and morbidity from missed malaria cases. English et al. also raise important issues about patient behavior. Patients with fever often get anti-malarials through informal mechanisms. If anti-malarials are linked to a positive test at the clinic but available for presumptive treatment at retail outlets, patients will get a mixed and confusing message. Finally, English et al. highlight the health system challenges of implementing such a policy change, arguing that we have been unable to purchase and deliver drugs reliably, and that we need to achieve high population drug coverage prior to taking on a new commodity (RDTs) which requires distribution and quality control.
So where does that leave me, looking at the problem from a resistance perspective? Assuming the chosen RDTs are effective, I am willing to give this policy change more thought. A well-designed pilot program might be the way to go, perhaps conducted in a few districts of an African country with trusted health system capacity and a relatively strong anti-malarial distribution system. Under such circumstances, I could be convinced to give policy change a try, but only if such a policy change is accompanied by provider training, community outreach and other key interventions. Providers need to try the RDTs, learn to trust their results, be given clear guidance on all possible algorithms, and perhaps be rewarded in some way for appropriate prescribing behavior. Consumers need to be engaged in creative ways and to be made aware of the fact that an anti-malarial should not be assumed to be the immediate solution to a child's fever. Educational efforts targeting both providers and consumers about the emergence of resistance caused by irrational drug use would be a critical component of any pilot program.
If you are interested in the global problem of drug resistance and what can be done about it, please see the Center for Global Development's Drug Resistance Working Group and sign up for the monthly newsletter.