Identification and Treatment of Undiagnosed Malaria Reduces Disease Prevalence

Actively identifying undiagnosed malaria and then treating those with the disease resulted in significantly lower prevalence of malaria cases compared to a control group.

A study was conducted in southern Zambia, with colleagues from the Johns Hopkins Malaria Research Institute in Macha (Zambia). Scientists analyzed data from surveys conducted in 2007 and between 2008 and 2009. In both surveys, households were screened for malaria using rapid diagnostic tests and treated with artemisinin combination therapy when malaria was detected.

A proactive test-and-treat case-detection strategy resulted in a six fold reduction in prevalence in 2008 and 2009, with the initial parasite prevalence at 4%. Test and treat showed a two fold reduction in 2007, when community prevalence was higher at 24%.

The prevalence of asymptomatic or minimally symptomatic malaria can be as high as 35% in populations with malaria. These asymptomatic individuals can serve as a reservoir for spreading malaria even in areas where disease transmission has declined.

The study findings were published in the February 3 edition of the journal PLoS ONE.

“New strategies are needed, particularly in areas of declining transmission. One strategy is to screen people for malaria and treat those who are infected, even those who are not sick enough to go to the clinic,” said lead author, Catherine G. Sutcliffe, PhD, an assistant scientist with the Johns Hopkins Bloomberg School of Public Health’s Department of Epidemiology (Baltimore, MD, USA). “Using artemisinin combination therapy can enhance this strategy, as treatment can reduce transmission to mosquitoes. In regions of declining transmission, the burden of malaria could be reduced to such an extent that elimination is achievable.”


The Johns Hopkins Malaria Research Institute at the Johns Hopkins Bloomberg School of Public Health focuses on a broad program of basic science research to treat and control malaria, develop a vaccine and find new drug targets to prevent and cure this deadly disease.

Related Links:
Johns Hopkins Malaria Research Institute in Macha
Johns Hopkins Bloomberg School of Public Health’s Department of Epidemiology