Virologist Martine Peeters, research director at IRD (French Institute for Research and Development) in Montpellier, publishes this Wednesday, September 15 with microbiologist Alpha Keita (University of Montpellier) in the prestigious British scientific journal Nature a fundamental discovery which changes the outlook on this deadly virus that has raged in West Africa since 2013. And beyond, raises questions about the behavior of other viruses. “It’s a new paradigm on epidemics,” says Nature.
In an article published this Wednesday, September 15 in Nature, you show that the Ebola virus which ravaged West Africa from 2013 to 2016, can wake up after five years. It’s a surprise ?
Yes, it’s a surprise that it stays “dormant” for so long. It was previously known that the virus could be found in semen, urine or breast milk in a person for up to eighteen months after recovery, and that person could then transmit the virus. But it depends on the individual: in half of the cohort we studied, only half of the people were positive six months after recovering.
How did you and your team come to this news?
We sought the origin of the viral strain of a resurgence of the epidemic, in Guinea, in February 2021, very close to the epicenter of the epidemic which had ravaged the country from 2013 to 2016. The analysis of the virus genome in the first cases of the new chain of transmission shows that it is the same strain. These first cases were contact cases of a nurse who died during the first wave, without it being known that she had been infected with Ebola. It was an asymptomatic case. But about twenty cases had been listed in his village.
It only takes one case for an epidemic to start again?
Lessons to be learned for the Covid?
Can your findings be of interest for other viruses, we are obviously thinking of Covid today?
Maybe it is not limited to Ebola, we cannot exclude that there is not the same phenomenon for the Covid, but we do not know what will happen, especially with long Covid.
Where is the Ebola epidemic today?
For the moment, there is no more epidemic. There are small resurgences, with the phenomenon described in Guinea this year, but also in the Democratic Republic of the Congo where we saw exactly the same virus reappear one year after the extinction of the epidemic.
How do we prevent an epidemic from starting again?
By setting up very rapid diagnostic tools, with trained personnel, treatments, vaccines. On this year’s episode, Guinea was very responsive, in three days. And the mortality associated with the virus, which was 90%, has increased to 60%, sometimes 50%.
Under these conditions, do you understand the current debates in France, on vaccination, protective measures such as the health pass?
I understand that we are asking questions, but there are limits. I think it’s better to get vaccinated.
Very deadly epidemics
Since 1970, at least thirty waves of Ebola epidemics have been identified in Africa, recalls Nature. The most severe affected Guinea, Sierra Leone and Liberia between December 2013 and June 2016. Nearly 29,000 cases were then recorded, with more than 11,300 deaths, including 2,500 in Guinea. The episode which struck Guinea in 2021 was less serious, with “an immediate response from the State” which made it possible “to quickly control the health situation”. Declared in February, it ended on June 19. In the meantime, 23 cases have been identified and 12 people have died.