Abuja- Nigeria is expected to be declared officially free of Ebola very soon, after six weeks with no new cases, World Health Organization said today.

Africa's most populous country won praise for its swift response after an infected Liberian diplomat brought the disease there in July.

The World Health Organization officially declared Senegal Ebola-free on Friday. The current outbreak has killed more than 4,500 people in West Africa, most in Liberia, Guinea, and Sierra Leone. An estimated 70% of those infected have died in those countries. The World Health Organization can officially declare an Ebola outbreak over if two incubation periods of 21 days pass with no new cases. The last reported case in Nigeria was discovered on 5 September. The outbreak there began when Patrick Sawyer, an American-Liberian citizen, was diagnosed with the illness in July.

Nigeria declared a national public health emergency and Sawyer later died of the disease, along with seven Nigerians. These included Dr Ameyo Stella Adadevoh, who diagnosed Sawyer and is credited with helping contain the outbreak at its source. John Vertefeuille from the US Centers for Disease Control and Prevention (CDC) said that Nigeria had taken the right steps to contain the outbreak.

"Nigeria acted quickly and early and on a large scale" he told sources. "They acted aggressively, especially in terms of contact-tracing", he added.