Nigeria’s Ebola outbreak seems to be nearing its end, say U.S. health officials who credit the country’s rapid response to a sick traveller for limiting spread of the disease.

On July 17, a very sick traveller who was in hospital in Monrovia, Liberia, developed a fever and left hospital against medical advice. He arrived at the international airport in Lagos, a densely populated city of 21 million, on July 20.

By the time health workers recognized that he was infected, he’d exposed 72 people on planes, the airport and the hospital.

On Tuesday, officials with the U.S. Centers for Disease Control and Prevention published an update on the response to the outbreak in Nigeria, which included 19 laboratory-confirmed and one probable Ebola cases.

"The threat to Nigeria posed by the arrival in Lagos of a patient acutely ill with Ebola was enormous," researchers said in CDC's Morbidity and Mortality Weekly Report.

The traveller died on July 25 with 894 contacts identified and followed. The final three contacts are due to leave followup on Oct. 2, at which point they'll receive an all-clear.

"Although Nigeria isn’t completely out of the woods, their extensive response to a single case of Ebola shows that control is possible with rapid, focused interventions," CDC director Tom Frieden said in a release.

Nigerian authorities took several quick actions, CDC said, such as:

  • Port Health Services began tracing potential contacts at the airport and sent out outbreak notifications.
  • Nigeria’s Health Ministry activated an emergency operations centre to lead the national response.
  • An epidemiology and surveillance team traced contacts, managed alerts and rumours and implemented surveillance in the community.
  • A social mobilization team went house-to-house within a specific radius of the homes of Ebola contacts.

While the researchers pointed to challenges, such as a lack of appreciation of the enormous consequences of even a small outbreak among all levels of political leadership, the decision to use an emergency operations centre and its precursor to respond "resulted in a rapid, effective and co-ordinated outbreak response," the researchers concluded.

They also pointed to Nigeria's experience dealing with previous outbreaks, such as lead poisoning response in 2010 and polio eradication efforts more recently.

A second report in the same issue describes how national preparedness and prompt communication across borders helped Senegal to avoid an Ebola outbreak after confirming its first case on Aug. 29 — a man travelling by taxi from Guinea to Dakar, Senegal, in a seven-person taxi to visit his family.

By Sept. 18, all 67 contacts of the Ebola patient had completed the 21-day followup with no further confirmed cases.