Various strains of Ebola virus

The first case of Ebola was reported in August 1976 in the Yambuku District of Zaire, now the Democratic Republic of the Congo (DRC), by Dr. Peter Piot, a Belgian microbiologist, who currently heads the London School of Hygiene and Tropical Medicine, and a team of infectious disease experts. The outbreak occurred near the Ebola River, earning the virus its name.

A second outbreak, called Sudan ebolavirus, occurred in Sudan between June and November 1976. While the spread of the earlier virus was contained within a 70km radius of Yambuku, the Sudan ebolavirus spread across four towns – Nzara and Maridi, which saw the most cases, and Tembura and Juba.

A 1978 report by the World Health Organisation (WHO) states that the 1976 Zaire ebolavirus, in which 318 people were infected and 280 died, began at the Yakubu Mission Hospital after a patient was treated for what was then thought to be malaria. Eleven out of the 17 hospital staff died in that outbreak.

Though the Ebola virus strains in the DRC and Sudan are the most common, there are three others: Reston virus (which is not infectious to humans), Taï Forest virus and Bundibugyo virus. The Zaire strain, which has up to 90% fatality rate, is the one currently ravaging Guinea, Liberia and Sierra Leone, where more than 6,000 people have died, as of December 2014.

In November, there was another unrelated Ebola outbreak in the DRC, where a pregnant woman was infected after eating bush meat.

About 67 cases and 49 deaths were reported in the DRC as of November 2014. The death toll in the DRC from all prior outbreaks combined stands at more than 1,590

By Yemisi Akinbobola