WHO Explains When a Country Can Be Declared Ebola-Free

As Kenya recorded its seventh Ebola case, the WHO said an outbreak can be declared over only after 42 consecutive days without a confirmed or probable case, counted from the last potential exposure to the final patient. The period is twice Ebola’s maximum incubation period and begins, among other circumstances, after recovery is confirmed by two negative PCR tests taken at least 48 hours apart, or after a safe burial if the patient dies. Authorities should intensify surveillance, monitor contacts and test suspicious community deaths during the observation period. The WHO recommends surveillance for at least six months after the outbreak ends, and continued care and testing of survivors for at least 18 months after the last confirmed patient recovers.