The Ebola virus has proven deadly to both people and animals.
The epidemic that started in 2014 has so far taken the lives of over eight thousand people in West Africa. The virus also killed an estimated 5,500 gorillas in the Lossi Sanctuary of the Republic of Congo in 2003. But scientists say the Ebola virus has been around far longer than the latest news headlines.
Dr. Robert Cohen is a preventive medicine physician at the U-S Army Public Health Command in Aberdeen, Maryland. In his studies of the origins of the virus, he found that the infectious disease and its strains have been around for millions of years. Key to its survival is its ability to mutate and transfer from primates to humans even as environmental conditions change, and populations grow.
So how does it spread?
“The short answer,” he said, “is that …it mutated into a strain that was able to jump into humans because of human encroachment into the forests [the natural reservoir of the virus], and the decline of other animal populations that might have shielded us from [it].”
Instead, Dr. Cohen highlighted humans have increasingly come into contact with bats, which carry Ebola.
“The continuous interactions and encroachments by humans into the forest,” he said, “has led to several instances of the spillover of this new strain of Ebola into humans.”
There are other diseases that mutate similarly to Ebola, whose genetic material includes an RNA [ribonucleic acid] virus. Its RNA is single-stranded, which scientists say makes it likely to spread more quickly than other viruses.
“RNA is the type that is Ebola, SARS, MERS, Avian flu etc. Single strand viruses tend to mutate faster than double stranded and almost all of the really bad pathogens that come from animals are single strand RNA viruses, just like Ebola,” said Dr. Cohen.
He said the worst of the viruses that jump from animals to humans is HIV, a disease that he says was very good in establishing itself in humans. So far, 40 million lives have been lost to HIV/AIDS and approximately 40 million people are living with the virus today.
“[In the] tropical rain forests of South America, Africa and southeast Asia, there is very high biodiversity, different types of animal species that harbor different types of viruses, and there are rarer viruses that the public is not aware of that the public health community is quite concerned about,” said Cohen, such as the Nipah a virus in southeast Asia and bird flu.
“There is very good reason to believe that if the trends that are bringing this about are not abated quickly we will see an epidemiologic pattern of worse and new RNA viruses or worse outbreaks in the relatively near future,” warned Dr. Cohen.