Ebola has become even more terrifying… This deadly virus that has spread sporadically in Africa since 1976, with a mortality rate that can range from 25% to 90% in humans, caused a new epidemic in February 2021 in Guinea. A total of 16 cases were confirmed before the outbreak was brought under control in June, of which 12 died. But this could in fact be just a continuation of the epidemic that occurred between 2013 and 2016 in West Africa, the deadliest in history with 11,300 deaths among Nearly 29,000 registered cases. Because, unlike in previous outbreaks where the first case was infected by an animal (mainly bats), it is more likely this time that this first case was actually a survivor of the previous epidemic, in which the virus would have been hiding. Five years before the revitalization in 2021, according to an article published on September 15 in the journal temper nature.
The outbreak in 2021 was caused by a strain of the 2013-2016 epidemic
Researchers from the Laboratory of the Guinea Hemorrhagic Fever and TransVIHMI Project at the University of Montpellier came to this conclusion after analyzing virus genomes from 12 cases in 2021. The evolutionary links between these viruses showed that they were running from the same group, due to a strain. of the virus that was already identified during the 2013-2016 epidemic. In fact, these 12 sequences were involved in 10 genetic changes that occurred during the previous pandemic, showing that the virus did not originate from a new animal disease, but five years ago.
The viral genomes of those 12 cases from 2021 differed from those from 2013-2016 by only 12 genetic changes. Very few suggest that the virus has not been transmitted from person to person for five years, a situation in which it should have accumulated about six times the number of mutations. So what’s more likely is that the virus has been at the same time of transmission as the person, and therefore has mutated very little in the past five years.
“The risk of resurgence is higher than ever.”
It has previously been observed that the Ebola virus can persist in an infected person’s body for about two years, and that survivors of the disease can retain antibodies to the virus in their bodies for a longer period, indicating that the virus can be hiding there. somewhere for years. One potential hiding place is semen, where the virus survives for at least six months in half of the male survivors. Other possibilities are other organs that are less “monitored” by the immune system, such as the eye and central nervous system.
This new post confirms these concerns, and highlights the possibility of a new Ebola epidemic from a survivor. “This means that the risk of re-emergence is higher than ever.”, alerted the researchers, who insist that survivors of previous epidemics should be closely followed in order to detect in a timely manner the possible reactivation of the virus. Finding a balance so that these people are not stigmatized and considered dangerous. An additional difficulty in fighting this terrifying virus.