Malaria detection using breath biomarkers
Although there were almost 200 million cases of malaria in 2013, resulting in over half a million deaths, this lethal infection is in retreat.1 Better control through prevention with insecticide-treated nets and more effective drugs (including artemisinin, for the discovery of which the 2015 Nobel Prize in Physiology or Medicine was awarded) mean that the ambition of elimination is again on the agenda. Sensitive diagnosis of malaria is becoming increasingly important, particularly for low-level and asymptomatic cases. Currently, most diagnoses of malaria use microscopy, which is not sufficiently sensitive to enable elimination and is dependent on highly trained operators with good equipment.
In a collaboration between the CSIRO and QIMR Berghofer Medical Research Institute, we tested the breath of volunteers who had been given a controlled Plasmodium falciparum malaria infection in a clinical trial of new drug treatments. The levels of four sulfur compounds in the breath of the volunteers consistently rose and fell with the life cycle of the parasite and cleared with the recovery process.2
It was particularly exciting that elevation of the levels of the sulfur compounds could be detected at the earliest stages of infection, when blood-smear microscopy is unable to detect the malaria infection. This finding suggests that the biomarkers could be exploited in…