New treatments for Ebola could be obsolete before they are available for use by patients, because of genetic mutations in the disease, scientists have warned.
They said they’d found 10 new mutations that might interfere with how three of the most advanced drugs work against Ebola. The drugs, including the experimental ZMapp given to several Ebola survivors, should be tested against the current strain, the researchers said.
Experimental drugs that are in development are designed to bind to and target pieces of the virus’ genetic sequence – or proteins produced from that sequence. But if the sequence changes, as a result of a ‘genetic drift’ – the natural evolution of the virus over time – the drugs may not work as effectively.
There is no drug on the market to treat Ebola, and no vaccine to prevent it, but clinical trials were accelerated last year after the worst outbreak in history began sweeping West Africa, killing more than eight thousand people so far and infecting more than 21,000.
All viruses mutate, some faster than others. Ebola changes slightly from outbreak to outbreak, and the more people or animals infected, the more likely the virus is to mutate as it replicates inside a living body.
“No one really knows right now what has the virus mutated to or if it has mutated,” Charles Chiu, a microbiologist and infectious disease expert at the University of California, San Francisco, told Reuters. “We’re not going to be able to determine in advance whether or not it has changed to a form where it might evade diagnostic assays or might render current vaccines or drugs ineffective” without new samples of the virus, he said.
Today, the Ebola virus spreads only through direct contact with bodily fluids, such as blood and vomit. But some of the nation’s top infectious disease experts worry that this deadly virus could mutate and be transmitted just by a cough or a sneeze.
“It’s the single greatest concern I’ve ever had in my 40-year public health career,” said Dr. Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. “I can’t imagine anything in my career — and this includes HIV — that would be more devastating to the world than a respiratory transmissible Ebola virus.”