Experts at a December 2012 WHO meeting agreed on a plan to eliminate sleeping sickness (human African trypanosomiasis), the Lancet reports. Highlighting the difference between eradication — “incidence is permanently reduced to zero cases worldwide and no further action is needed” — and elimination — “incidence is reduced to zero cases worldwide or in a defined geographical area but action might be needed to keep it that way” — the journal writes the goal is to bring the number of cases to zero, as eradication would mean ridding the world of the tsetse fly, which is responsible for transmission.

“Achieving the zero-cases-zero-transmission target, the WHO meeting participants agreed, will not be easy,” the Lancet notes and discusses a number of challenges, such as “a lack of field-friendly diagnostic tests” and the hunt for cases “in the remote jungle villages where most patients — and most tsetse flies — live.” However, “despite these difficulties, the meeting participants expressed few doubts about their ability to reach the zero-case target, at least for the west African form of the disease,” the journal notes, adding, “One reason for optimism is that the target was almost reached in the past” (Maurice, 1/5).