Science 363, 74–77 (2019)

Samples from the 2018 Nigerian Lassa fever outbreak were sequenced, and results indicated that it was a result of multiple zoonotic transmission events.

Lassa fever is an acute viral hemorrhagic fever that is contracted through exposure to infected rodents or, less frequently, through contact with the bodily fluids of infected humans. In early 2018, the outbreak was seen as unusually large, and there were fears of human-to-human transmission.

An international team applied Nanopore metagenomic sequencing to 120 Lassa-positive samples at the epicenter of the outbreak. Their analyses indicated that the outbreak was the result of multiple zoonotic transmission events. These results were communicated immediately, allowing for alteration of public health policy.