But the WHO said disease surveillance may not be at the best due to the low number of samples.
In its latest update Wednesday on the virus in West Africa, the U.N. agency noted signs that communities were still resisting bringing infected family members to treatment centers.
Only half of the 51 new infections in Guinea came from registered contacts of Ebola patients and some cases are only identified after post-mortem testing, it said.
The virus is still widespread in Sierra Leone, which recorded 81 new cases, including 26 in the capital Freetown.
"The number of confirmed Ebola virus disease deaths occurring in the community in Guinea and Sierra Leone remains high, suggesting that the need for early isolation and treatment is not yet understood, accepted or acted upon," the WHO said in a statement.
According to the WHO, more than 23,900 confirmed and suspected cases of Ebola have been reported since the outbreak began in December 2013, including some 9,800 deaths.
Nearly 500 health workers are among the victims.
LINA