Yesterday, when reporting on the latest tragic development in the wost ever Ebola outbreak to sweep through west Africa, namely that the head doctor tasked with containing the virus had himself contracted it, we commented that the "only good news, if any, is that even as the epidemic which has raged for months, and now appears to be out of control, it has not spilled out of Africa into other continents yet." That may not be the case for much longer following an update earlier today by Reuters that a Liberian man in his 40s is being tested for the deadly Ebola virus in Nigeria's commercial capital of Lagos, a megacity of 21 million people, the Lagos State Health Ministry said on Thursday.

This would be the first recorded case of one of the world's deadliest diseases in Nigeria, Africa's biggest economy and most populous nation, with 170 million people and some of Africa's least adequate health infrastructure.

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A Liberian man in his 40s is being tested for the deadly Ebola virus in Nigeria's commercial capital of Lagos, a mega-city of 21 million people, the Lagos State Health Ministry said on Thursday. A spokesman for the World Health Organisation (WHO) in Geneva confirmed Nigeria had "one suspect case" and said samples had been sent to a WHO lab for testing. "The Nigerian Ministry of Health has implemented control measures in the meantime," he told Reuters.

And the worst part: the man was at the airport when he was intercepted:

The special adviser on public health to the Lagos state government, Yewande Adeshina, told a news conference the man had collapsed on arrival at Lagos airport from Liberia on Sunday. He was rushed to hospital and put in an isolation ward, she said. "The patient was admitted and detained on suspicion of possible EBV (Ebola virus) infection, while blood sample collection and testing was initiated," she said in her statement, adding that "results are pending." Ben Neuman, a virologist and Ebola expert at Britain's University of Reading, said it was important to note that Ebola is one of a number of viruses that can cause hemorrhagic fever, and that others, including Lassa fever virus and Dengue virus, could turn out to be the diagnosis in this case. "Some of these other, more common hemorrhagic fever viruses have already been the cause of false alarms in the ongoing west African Ebola outbreak," Neuman told Reuters in London. "For now, it is important that we wait for the lab results on the patient in Lagos," he added. "Even if Ebola is confirmed, this will be a cause for concern, not panic. Ebola spreads slowly, and can be contained by quarantining suspected cases immediately in hospitals."

Soothing words aside, what is worse is that, if indeed confirmed that he has been infected, the scramble will now begin to find and quarantine any and all other people he may have been in contact with in recent weeks, a task which in a city of over 20 million - the world's fourth most populous city after Being and above Istanbul - will be like finding a rational thinker in the Princeton economics department.

And where things get really dicey is if any of those infected people were among the passangers who were at the Lagos airport at the time, and somehow managed to get on a plane in the last few days and departed for destinations unknown. At that point a watching of the 1995 Ebola thriller "Outbreak" may be in order.