Washington: An experimental vaccine protects monkeys from not only the two of the deadliest Ebola virus species, but also against a newer Ebola variant BEBOV, identified in 2007.
Ebola symptoms are headaches, fevers, chills, muscle aches and loss of appetite. Later, the patients experience diarrhoea, rash, sore throat, vomiting, abdominal pain and chest pain.
They have limited kidney and liver functions, besides internal and external bleeding. Patients die of shock, which is eight to 17 days after infection. The Ebola virus also suppresses the immune system.
Nancy J Sullivan of the Vaccine Research Centre at the National Institute of Allergy and Infectious Diseases (NIAID) led the study team, including those from the US Army Medical Research Institute of Infectious Diseases and Centres for Disease Control.
Currently, there are no specific treatments or vaccines available to control Ebola outbreaks.
"The important work by Dr Sullivan and her colleagues shows that it is possible to generate immunity to newly identified species of Ebola virus with a vaccine originally designed to protect against a different species," said NIAID director Anthony S Fauci.
"This finding will guide future vaccine design and may open an avenue for developing a single vaccine that works against both known and emerging Ebola virus species."
More importantly, the experimental vaccine induces a robust reaction by the cellular arm of the immune system. The cellular arm includes T-cells, which help orchestrate the overall immune response.
"An ideal Ebola vaccine would stimulate broad immunity so that we wouldn`t have to scramble to create entirely new vaccines whenever new virus species are identified," notes Sullivan, according to a NIAID release.
Now the research team is evaluating what parts of the T-cell response were critical to the vaccine`s success against BEBOV.
"Once we identify those critical aspects, we can design future vaccines to better elicit that desired immune cell-based activity and perhaps make a single vaccine that protects against all Ebola virus species," says Sullivan.
Their findings appeared on May 20 in the open-access PLoS Pathogens.