Nigeria is garnering praises for what experts describe as a "quick and forceful" response to quash Ebola and stop it from wreaking havoc in Lagos, the country's capital and the largest city in Africa.

The World Health Organization (WHO) has officially declared Ebola-free on Monday after no new cases have been reported since September 5. For a country to be declared Ebola-free, it has to go 42 days or twice the incubation period without a new case, while proving that it has actively sought out all possible contacts and show negative results for all suspected cases.

"The virus is gone for now. The outbreak in Nigeria has been defeated," says Rui Gama Vaz, Nigeria representative of the WHO. "This is a spectacular success story that shows to the world that Ebola can be contained but we must be clear that we have only won a battle, the war will only end when West Africa is also declared free of Ebola."

On July 20, Liberian-American man Patrick Sawyer flew in from Liberia carrying the deadly Ebola virus into Lagos. He was in the latter stages of the disease, and airport officials transported him to a hospital where Sawyer was first treated for malaria. After three days, the symptoms have not abated and medical staff moved quickly to treat Sawyer as a possible Ebola patient. On July 23, Sawyer was diagnosed with Ebola. On that very same day, the Federal Ministry of Health, in cooperation with the Center for Disease Control and Prevention, formed the Incident Management Center, which later became the Emergency Operations Center (EOC), to coordinate the national response.

"We used a war-room approach to coordinate the outbreak response," says Dr. Faisal Shuaib of the EOC. "So you have a situation whereby government and staff of international development agencies are co-located in a designated facility where they are able to agree on strategies, develop one plan and implement this plan together."

The EOC deployed more than 150 contact tracers, workers who visited more than 18,500 homes of people who may have directly or indirectly had contact with people who have been infected with Ebola. Folorunso Oludayo Fasina, senior lecturer at the University of Pretoria and co-author of a paper showing in more detail how Nigeria responded to the outbreak, says contact tracing proved to be one of the most challenging tasks, especially in Nigeria where houses don't always have street numbers.

Fasina says contact tracers also had to work around the social stigma of being associated with Ebola to cajole people to submit to check-ups. A group of what Fasina calls "social mobilizers" also went around to 26,000 homes of families living near the homes of Ebola patients to educate them about the symptoms of the virus and how to prevent it from spreading. Gavin MacGregor-Skinner of the Elizabeth R. Griffin Research Foundation, which provided assistance during the response, says Nigerian officials sent a message to its citizens to "really make them look like heroes" to remove the stigmatization of the disease.

"This is the best thing people can do for Nigeria: They are going to protect and save Nigeria by being honest, by doing what they need to do, by reporting to the health commission," says MacGregor-Skinner. "You got real engagement and compliance from the contacts. They're not running and hiding."

Once a person is seen with Ebola symptoms, health officials swooped in to move the patient to an isolated ward at the Lagos University Teaching Hospital, where rapid diagnosis is made. If tested positive, the patient is moved to a special treatment center. Those who tested negative but showed symptoms of Ebola were still placed in isolated wards separate from the Ebola patients for further monitoring.

However, even if the country has already been declared Ebola-free, health officials are not about to ease up and the government continues to monitor the possibility of future cases.

"Outbreak response preparedness is a continuous process that requires constant review of the level of the response mechanisms in place to ensure that the health system is ready to jump into action at all levels," says Shuaib. "There is no alternative to preparedness."