The outbreak of Ebola in Senegal is officially over but the country remains vulnerable to further cases of the deadly disease being imported, the World Health Organization (WHO) said on Friday.

Twice the maximum incubation period of 21 days, or 42 days, has passed since a Guinean man who traveled to Dakar was confirmed as having Ebola, it said in a statement praising Senegalese authorities for their “diligence”.

The man has recovered and his 74 known contacts have not caught the disease.

“While the outbreak is now officially over, Senegal’s geographical position makes the country vulnerable to additional imported cases of Ebola virus disease. It continues to remain vigilant for any suspected cases by strict compliance with WHO guidelines,” the U.N. agency said in the statement issued in Geneva.

Nigeria is also due to be certified as Ebola free by 20 October, exactly 42 days since the last case was reported in Port Harcourt.

At the 68th UN General Assembly, President Jonathan told the world that Nigeria was Ebola free. Experts said he jumped the gun and that he should have waited till next week.