The Longest Mile: Moving Malaria from Clinical Care to Elimination of Transmission.

Abstract

Finishing a task is generally more difficult than starting—the “longest mile is the last mile home.” This is particularly true in the battle against global infectious diseases. Smallpox remains the only human disease to have been completely eradicated, with the last known natural case in 1977. Seven other human diseases have been deemed eradicable by the International Task Force for Disease Eradication: dracunculiasis (Guinea worm), poliomyelitis, mumps, rubella, lymphatic filariasis, cysticercosis, and measles. Yet, despite significant progress, eradication of these diseases remains a tremendous global health challenge. Many other infectious diseases, including malaria, are considered “eliminable,” indicating cessation of transmission in a limited geographic area. Although previous ambitious WHO efforts toward global eradication of malaria ultimately fell short (1955–1978), successful elimination of malaria has been achieved in many nations that have temperate climates and seasonal malaria transmission. In the past 2 decades, interest in the malaria “end game” has resurged, galvanized in 2007 by a renewed call for and commitment to malaria eradication by the Bill and Melinda Gates Foundation. Malaria control efforts depend on detection and effective intervention; thus, public health programs must understand which populations are affected. As efforts move toward elimination and ultimately eradication, a particular challenge will be the need to root out reservoirs of transmissible infection with Plasmodium spp. parasites, including identification of asymptomatic individuals who lack clinical manifestations of infection. In a recent article, Tao et al. reported the discovery and validation of a novel saliva-based test for detecting subclinical malaria infection (1). The investigators hypothesized that Plasmodium spp. parasites sequestered in capillary beds within the oral mucosa might produce distinct proteins detectable in saliva. Using a mass spectrometry-based proteomics approach, they screened pooled saliva from asymptomatic children with submicroscopic Plasmodium spp. blood-stage …