In a study published in the prestigious scientific journal Nature, Guinean and French researchers show for the first time that an Ebola epidemic, like the one that occurred in Guinea in 2021, can be explained from a “sleeping” virus strain in a person, more than five years later. to have been infected. Although the phenomenon would be extremely rare, this discovery underscores the importance of monitoring the survivors.
On February 14, 2021, the Guinean government announced that an Ebola virus epidemic had broken out in N’Zérékoré prefecture. By mid-June, the epidemic is over, causing the deaths of 12 people out of 23 identified cases. The study was published in Nature on Wednesday, September 15, with the title “Resurrection of the Ebola virus 2021, Guinea: A new paradigm of epidemics”, confirms that the virus strain responsible for this epidemic is the same as that which affected the country five years earlier. The 2021 epidemic is therefore not of animal but human origin, and patient 0 is probably a survivor of the previous epidemic.
Supporting survivors to understand Ebola Approximately 17,000 patients survived the epidemic that lasted from December 2013 to June 2016 in West Africa. Together with Guinean researchers Saliou Sow, Abdoulaye Touré and Alpha Keita, the Frenchman Eric Delaporte, professor of infectious diseases at the University of Montpellier, has followed more than 800 survivors in Guinea, out of the 1,270 registered in the country.
“We had to take care of the survivors when we left the Ebola treatment centers, because they were usually traumatized mentally and physically,” he explains. ), in Conakry. And thus we have been able to make enormous progress in understanding the infection. “During the pandemic, after leaving the treatment center, most survivors were sent home without special follow-up.” It is as if you are coming out of intensive care and you have to stand up for yourself. “
“The centers proceeded according to the recommendations of the time. The survivors were declared cured, but on a biological basis, that is, there was no longer any virus in the blood: there was no treatment program yet, ”Eric explains. Door. But we know today, thanks to a previous study by the same researcher, that the consequences associated with the infection are many and that the virus can live in fluids other than blood.
Persistent symptoms were thus observed in three quarters of the survivors at the beginning of the follow-up, especially leg and joint pain, neurological disorders or even inflammatory glaucoma. “Over time, these manifestations decrease significantly – today only a third of the survivors are worried – with very moderate attacks,” the professor assures.
The results of the analyzes of the strain of the 2021 epidemic surprised researchers at Cerfig, associated with the Institute for Research for Development (IRD) and the German Robert Koch Institute. Eric Delaporte, IRD, testified: “We did not expect to find the same strain as at the end of the 2013-2015 epidemic. We told ourselves that we had to verify that it was not a laboratory contamination. “Three other laboratories, including one Guinean and one Senegalese, performed new analyzes. Everyone finds the same result, which destroys the perception of the Ebola virus disease: this strain can only be transmitted by a human, a survivor of the previous epidemic, whose virus has been reactivated.
Support, vaccinate, without stigmatizing In their press release announcing the publication of the study, the researchers insist: we must fight against the stigmatization of survivors, who may be put aside by their loved ones for fear of resuscitation. “The phenomenon is still extremely rare,” Professor Delaporte insists. After observing clinical sequelae after the acute phase of infection, the researchers would like the survivors to be followed up systematically. They also suggest that those with low antibody levels be vaccinated against Ebola: without a vaccine, some may not be able to control a reactivation of their dormant virus.
Natalie Roberts, an emergency physician at Médecins Sans Frontières who has studied the Ebola virus, insists that vaccination should be offered to everyone. “In some affected countries, population movements are important and public health infrastructure is weak. It is probably not realistic to want to follow all the survivors for years “, she warns. On the other hand, vaccination seemed to be a more realistic solution: “In addition to vaccinating survivors, who should strengthen their antibodies, we can think of their sexual partners and other people around them who will be exposed to body fluids from survivors. “.
Basic research on treatments should also be intensified. It has been shown that well-targeted monoclonal, ie artificial, antibodies can control the infection but not kill the virus. Today we need virucidal drugs if we want to permanently eliminate the virus from the body in the rare cases where it sleeps, resting, says Professor Delaporte.
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