Ebola – the not so new virus

   Ebola-poster

Ebola in West Africa has claimed more than 9300 lives in the last year.

Researchers have traced the origins of the epidemic to a two-year-old toddler, who died in December 2013 in Meliandou, a small village in south-eastern Guinea. The child was seen playing under a tree heavily infested with bats.

AT “Ebola: The 21st century plague?" [Royal Society of Medicine, London, UK. February 6, 2015], we heard from international experts handling the epidemic.  They examined the history of the disease, the lessons learnt from 2014 and what strategies are in place for preventing future outbreaks.  In doing so, we gained an explanation as to why a rural outbreak became a regional urban epidemic, and an understanding of the complexity of medical volunteering and running ebola treatment centres.

I have selected some keyfacts & insights from the talks, to give you a flavour of this one-off national symposium, an update from the frontline. This blog also appears on our monthly Global Health Knowledge Base, along with relevant ebola research and news.

Ebola virus has been with the world since at least 1976 – nearly 40 years
We are aware of 28 independent outbreaks of the ebola virus disease in that time, from 5 different strains named for each country of origin and all but one in Africa. What's different this time is that the death toll is so much higher.

Keyfact:  4 times as many deaths in one year as in the previous 40 years

Insight: Although ebola has been around for some time – and probably longer than we realise – the global community only became aware of it because a nun at a missionary clinic went down with a mystery disease caught from patients. Her blood sample sent to London in 1976 yielded a new virus – which was named "Ebola" after the river near to the outbreak village in Yambuko, DRC.  At the same time, 500 miles away in Sudan, a similar but separate outbreak occurred.

Ebola in West Africa largely confined to Guinea, Sierra Leone and Liberia
These have vast rural areas, with dense forest and wild life in close proximity to the local population, perfect for transmission of a virus from wildlife to people (zoonoses).

Keyfact: Right from 1976, wildlife transmission was suspected and the search for an animal reservoir began.   The index case for the 1976 Yambuko outbreak was a headmaster who had eaten monkey meat, the simulatenous Sudan outbreak was centred on a sugar factory infested by bats; a vet caught ebola from treating a sick chimpanzee colony in Cote D’Ivoire[1992]

Insight: In 1996,  a lab study finally showed that of various mammals, only bats could be infected and remain healthy (=reservoir)

 

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