0243 GMT January 23, 2020
“The response to the EVD (Ebola virus disease) epidemic has now moved to a second phase, as the focus shifts from slowing transmission to ending the epidemic,” the WHO said in its latest report on the disease yesterday.
There were 99 confirmed new cases last week, the lowest number since June, theatlantic.com reported.
But researchers at the Institut Pasteur, the French medical-research organization that first identified the outbreak in Guinea last March, said that they’re trying to determine whether the Ebola virus is becoming more contagious.
"We know the virus is changing quite a lot,” Anavaj Sakuntabhai, the head of the Laboratory for Genetics of Human Response to Infection at the Institut Pasteur, told the BBC.
Specifically, he said, there have been a number of asymptomatic cases, meaning that infected people may unknowingly be spreading the disease: “A virus can change itself to less deadly but more contagious, and that's something we are afraid of.”
Sakuntabhai and his colleagues are currently analyzing hundreds of blood samples from Guinean patients to monitor the virus’s evolution.
"That's important for diagnosing and for treatment," he said. “We need to know how the virus [is changing] to keep up with our enemy."
"We know the virus is changing quite a lot. It can become less deadly but more contagious, and that's something we're afraid of."
Ebola, like measles, HIV and influenza, is an RNA virus, meaning it can mutate quickly and often. In August, a paper published in the journal Nature found that the virus had already evolved several times over in the first month of the outbreak in Sierra Leone (five of the paper’s authors died of Ebola before their work was published), though there is still nothing to suggest that the virus has become airborne, a common fear over the course of the epidemic, or that it has evolved out of reach of existing treatments.
"The mutations do not seem to be affecting the efficacy of experimental drugs and vaccines," Nature reported of the Sierra Leone paper in August.
"It isn't surprising at all that the virus is mutating," said Anthony Fauci, the head of the National Institute for Allergy and Infectious Diseases, but "I haven't seen any compelling data yet that the mutations are associated with a change in the function of the virus."