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- Drugs and requirements: without a vaccine, the Ebola outbreak in Africa will drag on for years
Drugs and requirements: without a vaccine, the Ebola outbreak in Africa will drag on for years
The Ebola outbreak in the Democratic Republic of the Congo will end after the formation of population immunity, which, according to Alexander Ginzburg, the scientific director of the Gamalei Center, may take several years. The creation of a vaccine against the Bundibugio strain can change the situation. However, experts note that the timing of its development is still impossible to predict. The creators of the domestic vaccine are ready to conduct experiments with a live virus if African countries show interest in such research. Oxford University and Moderna have also announced the start of trials of their own drugs. The number of cases in the DRC exceeded 4 thousand people. In the absence of effective means of combating the new variant of the virus, WHO recommends testing the effectiveness of an existing vaccine against it.
How long will the Ebola outbreak last
In the absence of a vaccine against the Ebola Bundibugio strain, which caused the current outbreak in the Democratic Republic of the Congo, the epidemic can end only after the formation of natural population immunity. This process can take years, Alexander Gintsburg, the scientific director of the N.F. Gamaleya Center, told Izvestia.
— It is difficult to predict the timing of the end of the outbreak. Since there is no vaccine now, it cannot be localized with vaccinations. The local population is constantly in contact with this virus and receives protection literally with its mother's milk, meaning that a significant part of the population is already protected in this way, especially in rural areas. Others will get over it. And the outbreak will stop when population immunity is naturally formed. The speed of its formation will depend on how actively the inhabitants are moving. But these are not months, but years," the scientist said.
Immunologist Mikhail Bolkov also believes that the Ebola epidemic may drag on for several years. According to him, the infection is spreading among new populations in Africa, where there are no full-fledged sanitary cordons and access to medical care is often limited.
— Immunization with vaccines could make a difference. But it is almost impossible to predict when doctors will actually receive such a drug. To do this, the vaccine must first be tested, and the timing of clinical trials varies greatly from case to case. Then it will be necessary to organize vaccination, which also depends on the situation "on the ground." Besides, there's a war going on there," he said.
The experience of previous Ebola outbreaks shows that vaccination can be an effective tool for localizing infection, said Sergey Voznesensky, associate professor of the Department of Infectious Diseases with courses in Epidemiology and Phthisiology at RUDN University.
— Vaccines against the Zaire Ebola strain have demonstrated effectiveness in the region. Therefore, if it is possible to create an equally effective drug against Bundibugio, there is a high probability that the outbreak will be stopped without waiting for the formation of natural population immunity, the expert believes.
According to the latest data, the number of cases of Ebola infection in the DRC has reached 4,120 people, 1,887 have died, including more than 300 children. The mortality rate was 45.8%. This is the second largest outbreak of Ebola in the history of observations. Against the background of the deteriorating epidemiological situation, doctors from the African Centers for Disease Control and Prevention (Africa CDC) plan to conduct apartment-by-apartment visits to identify infected people.
— In addition, we need to check if there are any additional problems and if the virus is mutating. Because the severity of this outbreak of Bundibugio is unprecedented," said the head of the organization, Dr. Jean Kaseya.
Creating a vaccine against Bundibugio
Bundibugio vaccines are being developed in several countries at once. Moderna has announced the start of clinical trials of its mRNA drug in Canada: the first doses were given to participants in Phase I trials. A total of 80 people are planned to be involved in the study. About a month ago, Oxford University also announced the start of trials of the ChAdOx1 BDBV vaccine.
As previously reported by Izvestia, a domestic vaccine developed at the Gamaleya Center has successfully passed tests on an artificially created virus surrogate. Experts are ready to continue research on the live pathogen in case of interest from African countries.
— We made vaccine producers and showed their immunogenicity and protectivity in surrogate tests for simplified versions of the virus. They correlate well with the virus itself and were the first step towards proving that the vaccine is effective," Denis Logunov, director of the N.F. Gamalei Research Center for Epidemiology and Microbiology, told Izvestia.
Since there are no effective means of combating Bundibugio yet, the WHO technical advisory group recommended that the registered vaccine against the Zaire strain of Ebola, Ervebo, be included in clinical trials to test its effectiveness against the current threat. The organization's experts have studied the preliminary results of animal studies. They showed that the vaccine provides a certain level of cross-protection against the Bundibugio virus, in particular, it reduces the risk of death from the disease.
The WHO officially announced the start of the current outbreak on May 15. However, the journal Science reported that the research team identified about 500 suspected cases in DR Congo that occurred from mid-January to mid-May. Thus, the infection could spread unnoticed for almost six months.
Переведено сервисом «Яндекс Переводчик»
