The medics will boost weak local health systems that are also struggling to contain other preventable diseases as Ebola discourages people from going to clinics for fear of contracting the fever.
The worst outbreak of Ebola on record has killed at least 6,187 people in the three worst-affected countries - Liberia, Sierra Leone and Guinea - according to the latest data from the World Health Organization.
"This is the African spirit you are showing, this is the Nigerian spirit," Nigeria's ambassador to Liberia, Chigozie Obi-Nnadozie, told 76 Nigerian medics who landed there.
Another 100 volunteers landed in Freetown, Sierra Leone.
Months into the Ebola response, experts say they are still short of medical personnel to staff treatment centers.
The United Nations said one of its peacekeepers in Liberia had contracted Ebola, making him the third infected member of the mission. The two others have both died.
Sixteen people who came into contact with the peacekeeper while he was symptomatic had been identified, the United Nations said.
The condition of an Italian doctor who contracted Ebola in Sierra Leone and was flown home last month has worsened, a Rome hospital said on Friday.
Liberia - the country with the highest number of cases - has succeeded in lowering infection rates, and the virus is now spreading fastest in Sierra Leone. The former British colony recorded 537 new cases in the week to Nov. 30.
U.N. child agency UNICEF on Friday began a campaign to provide 2.4 million people in Sierra Leone with anti-malarial drugs to ease the strain on the healthcare system and allow Ebola cases to be identified more easily. The two diseases have similar symptoms, including headaches, fever and aching joints.
Liberia's President Ellen Johnson Sirleaf issued an order banning rallies and public meetings ahead of a Senate election scheduled for later this month, saying the move was part of the fight against Ebola.
Amid signs of a slowdown in the epidemic in Guinea - where the virus was first detected in March - neighboring Guinea-Bissau said it would reopen their shared border by next week.
(Additional reporting by Alphonso Toweh in Monrovia, Stephanie Ulmer-Nebehay in Geneva and
Sent from my BlackBerry® smartphone, powered by Easyblaze