Rift Valley fever (RVF) is an emerging zoonosis posing
a public health threat to humans in Africa. During sporadic
RVF outbreaks in 2008–2009 and widespread epidemics in
2010–2011, 302 laboratory-confirmed human infections, including
25 deaths (case-fatality rate, 8%) were identified. Incidence
peaked in late summer to early autumn each year,
which coincided with incidence rate patterns in livestock.
Most case-patients were adults (median age 43 years),
men (262; 87%), who worked in farming, animal health or
meat-related industries (83%). Most case-patients reported
direct contact with animal tissues, blood, or other body fluids
before onset of illness (89%); mosquitoes likely played
a limited role in transmission of disease to humans. Close
partnership with animal health and agriculture sectors allowed
early recognition of human cases and appropriate
preventive health messaging.