The Ebola Virus Disease (EVD) outbreak in West Africa reached the one year anniversary this month when the initial case was reported in Guinea. One year later, the number of cases reported to date is closing in on 20,000, making it by far the largest known outbreak of the filovirus disease (the previous largest outbreak involved 425 cases).

Image/CDC
Image/CDC

Since the first case was confirmed in Sierra Leone in May 2014, the West African country has become the hotspot for the disease, now accounting for more than 9,000 cases, or nearly half (46%) of the cumulative cases in West Africa (19,463).

The World Health Organization (WHO) reports that EVD transmission remains intense in Sierra Leone, with 315 new confirmed cases reported in the week to 21 December. While there are signs from the country situation reports that the increase in incidence has slowed and the incidence may no longer be increasing, disease transmission in the affected countries is currently most intense in the western and northern districts of Sierra Leone.

Freetown, the capital of Sierra Leone, remains a hotspot for Ebola accounting for a third of the cases reported that week.

Guinea reported the most cases in one week during this outbreak the week to Dec 21 with a total of 156 confirmed cases. Health officials say this is largely due to a surge in cases in the south-eastern district of Kissidougou.

In Liberia, the good news is case incidence has been declining at a national level since mid-November, although transmission remains intense in the country. A total of 21 confirmed cases were reported in 5 districts in the week to 21 December.

EVD cases were first confirmed in Liberia in late March 2014. The total cases reported to date stands at 7,862, including 3,384 deaths.

How long is the West Africa Ebola outbreak expected to last?

At least one expert says until this time next year. In a BBC report Wednesday, Dr. Peter Piot, one of the scientists who discovered Ebola in 1976 and is now Director of the London School of Hygiene and Tropical Medicine said the epidemic could have a “very long tail and a bumpy tail”.

“The Ebola epidemic is still very much there. People are still dying, new cases are being detected,” he told the BBC World Service’s Newsday programme.

“We need to be ready for a long effort, a sustained effort for probably the rest of 2015.”

A total of 19,463 confirmed, probable, and suspected cases of EVD and 7,573 deaths have been reported up to the end of 21 December 2014.

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