New mutations in the deadly Ebola virus which could open it up to future cures and vaccines have been found by scientists.
They also discovered the current outbreak had a common source dating back to the mid-70s and was transmitted from Guinea to Sierra Leone by 12 people who had attended the same funeral in May.
Researchers from the Broad Institute and Harvard University collected data from 78 patients who contracted the disease during the first 24 days of the outbreak in Sierra Leone.
They found more than 300 genetic changes in the 99 genomes they sequenced which were distinct from previous outbreaks.
Using a “deep sequencing” technique, the team took an extremely close-up view of samples from each patient. This high-resolution view allowed the team to detect multiple mutations that alter protein sequences – potential targets for future diagnostics, vaccines, and therapies.
Working with the Sierra Leone ministry of health and sanitation, they also discovered the strains responsible for the current outbreak were likely to have a common ancestor dating back to an outbreak in 1976.
To accelerate the search for a cure, the team released the full-length sequences on a National Centre for Biotechnology Information’s (NCBI’s) DNA sequence database.
Co-author Pardis Sabeti, an associate professor at Harvard University, said: “By making the data immediately available to the community, we hope to accelerate response efforts.”
The news came as the World Health Organisation yesterday announced the Ebola epidemic in West Africa could infect more than 20,000 people, with the UN agency warning that an international effort costing almost half a billion dollars is needed to overcome the outbreak.
At the same time, GlaxoSmithKline said an experimental Ebola vaccine is being fast-tracked into human studies and it plans to produce up to 10,000 doses for emergency deployment if the results are good. The WHO estimates it will take six to nine months to halt the Ebola epidemic in West Africa, while officials in Nigeria yesterday said a doctor involved in treating a Liberian-American who brought the disease to the country had died in Port Harcourt.
So far, 3,069 cases have been reported in the outbreak but the WHO said the actual number in Guinea, Sierra Leone, Liberia and Nigeria could already be two to four times higher.
“This is not a West Africa issue. This is a global health security issue,” Bruce Aylward, the WHO’s assistant director-general for polio, emergencies and country collaboration, told reporters in Geneva.
With a fatality rate of 52 percent, the death toll stood at 1,552 as of 26 August. That is nearly as high as the total from all recorded outbreaks since Ebola was discovered in the Democratic Republic of Congo in 1976.
The figures do not include deaths from a separate Ebola outbreak announced at the weekend in Congo, which is a different strain of the virus.
Mr Aylward said tackling the present epidemic would cost an estimated $490 million (£296m), involving thousands of local staff and 750 international experts.