Ebola epidemic spreads in central Africa Declared a “public health emergency of international concern”“By the World Health Organization (WHO).
till 22 mayMore than 800 Ebola cases have been reported in the Democratic Republic of the Congo, including more than 180 deaths; These counts include both suspected and laboratory-confirmed cases of the disease. There are also two confirmed cases and one death in Uganda, primarily among people who recently traveled to the DRC.
Experts told Live Science that several factors are making it very challenging to stop this outbreak — here’s what’s what.
current ebola outbreak
WHO officials suspect Ebola outbreak concentrated in DRC Might have started about two months ago. Authorities say the first suspicious death occurred on April 20 and may have been followed by a superspreader event at a funeral or health facility. Reuters also reported Medical personnel failed to send samples of the first patient for further tests after they came back negative for a variant of Ebolavirus.
That virus – known as Ebola virus or Zaire ebolavirus – is the most common culprit behind Ebola disease outbreaks and deaths. There are two other viruses that cause the spread of Ebola disease: Sudan virus and Bundibugyo virus. The latter is driving the current outbreak.
There are only a few travel related cases in Uganda receiving an american care The outbreak in Germany is centered in the DRC, after being infected in Congo. However, WHO feared a high risk of international spread, prompting the agency’s leader to declare an emergency without convening a committee to discuss the decision.
The WHO director-general said, “In our view, the scale and speed of the pandemic requires urgent action.” Tedros Adhanom Ghebreyesus Said 19 may.
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a virus for which there is no vaccine
Part of the challenge with prevention is that there is no effective vaccine against Bundibugyo virus, the germ that caused the pandemic.
Ebola vaccines are approved. “However, these vaccines are designed specifically to address Zaire ebolavirus,” which has historically caused larger outbreaks than Bundibugyo virus, he said. Dr. Madeline DiLorenzoClinical coordinator of infectious diseases operations and an associate hospital epidemiologist at Tisch Hospital at New York University (NYU) Langone. The largest Ebola outbreak everThat occurred from 2014 to 2016, involving the Zaire ebolavirus.
Zaire ebolavirus and Bundibugyo virus are genetically distinct, sharing only 60% to 70% of their genetic material. DiLorenzo explained that the protein targeted by existing Ebola vaccines is encoded by a specific gene, and the sequence of that gene varies between the two viruses.
Studies show that the immune response against filoviruses – the family of viruses that includes Zaire ebolavirus and Bundibugyo virus – Show limited cross-reactivityWhich means the immune response focuses on only one type of virus. So Zaire-targeted vaccines likely won’t help in this outbreak.
Currently, there is no effective vaccine for Bundibugyo virus.
(Image credit: Shutterstock)
WHO officials have said There is a promising experimental vaccine against Bundibugyo virus, but no doses are available for clinical trials. WHO estimates it could take six to nine months to manufacture those doses. Another vaccine may take two to three months to develop, but its efficacy is unknown as scientists are still awaiting the results of laboratory-animal tests.
During the Ebola outbreak, Vaccines used for ring vaccinationIn which people who have come in contact with a suspected or confirmed case are vaccinated against the disease. They can also be used for “targeted geographic vaccination”, in which everyone in a given area is vaccinated because the outbreak is relatively concentrated there or contact tracing is very difficult. Without the Bundibugyo vaccine, both of those strategies are currently off the table.
lack of diagnosis and treatment
Ebola disease can be difficult to recognize in its early stages, partly because first symptom Quite common are: fever, fatigue, malaise, muscle aches, headache and sore throat. These symptoms appear within two to 21 days of exposure to ebolavirus.
There are tests for Bundibugyo virus that look for genetic material of the virus in bodily fluids; This approach is known as PCR testing. “However, this is not widely available for Bundibugyo virus, making it difficult to diagnose and, as a result, difficult to contain the virus.” Dr. Jill WeatherheadAn associate professor of infectious diseases and tropical medicine at Baylor College of Medicine told Live Science in an email.
DiLorenzo said that even when such tests are available, it can take several days after symptoms develop for the virus to be detected in a patient’s blood, so repeat testing may be necessary. Recommended samples for Ebola testing are whole blood or plasma for living patients and oral swabs for deceased individuals. WHO says.
There are additional tests that can detect Bundibugyo virus, including some that determine whether a sample contains filoviruses that commonly infect humans, without specifying which one is present. These rapid tests look for specific viral proteins. However, these tests are less sensitive and “cannot capture the specific proteins associated with bundibugyo,” DiLorenzo said. “This may delay detection of the current outbreak in the DRC.”
In the current outbreak, WHO says the risk of spread is “very high at the national level, high at the regional level and low at the global level.”
(Image credit: Michelle Lunanga/Stringer via Getty Images)
Apart from these diagnostic challenges, there are no specific antiviral treatments for Bundibugyo virus. There are lab-made antibodies approved for Zaire ebolavirus, and they improve survival by binding to the surface of the virus and preventing it from infecting cells. Weatherhead said similar treatments for Bundibugyo virus have not advanced beyond laboratory research or early-stage human safety studies.
Conflict, declining foreign aid hamper control
Weatherhead said that in the absence of vaccines and treatments, other strategies, such as isolating close contacts of infected people, become key to stopping the outbreak. He said physicians treating patients with suspected or known cases should also follow strict infection-prevention and control protocols to prevent further spread.
Ebola is spread by contact with infected blood and other bodily fluids, as well as contaminated surfaces or materials, such as clothing and bedding. This means using personal protective equipment to prevent splashing or other contact with infected material, among other protocols.
The strategies available to contain this outbreak – finding and isolating cases and implementing stringent infection-control protocols – require public health infrastructure to execute. But in the DRC, that infrastructure has been seriously compromised. The epicenter of the outbreak is Ituri province in northeastern DRC, which “has experienced decades of armed conflict, making it challenging for health systems to function optimally there,” DiLorenzo said.
joshua walkerProgram Director of Congo Research Group The circumstances of the current outbreak are similar to the 2018-2020 outbreak, which was centered on North Kivu province, which borders Ituri to the south, NYU’s Center on International Cooperation told Live Science via email.
Funding cuts don’t directly cause pandemics, but they weaken the systems that are in place to prevent small crises from becoming larger ones.
Dr Manenzi Mangundu, DRC Country Director of Oxfam
This time, several cases have been reported in both North and South Kivu provinces, parts of which are essentially divided between the DRC government and a Rwanda-backed rebel group, known as M23. And violence between armed groups has been increasing in Ituri in recent months, Walker said. Meanwhile, development assistance for health care in the region has declined significantly in recent years. Taken together, these factors “will make access and coordination of a single response much more difficult,” he said.
Dr. Manenzi Mangundu, Oxfam’s DRC country director, said recent cuts in foreign aid are making the situation worse. which is coordinating grassroots responses to the outbreaktold Live Science in an email.
“U said [the U.S. Agency for International Development] was the main donor in the DRC and many aid organizations were already dependent on its funding to provide life-saving assistance in the conflict-ravaged country.” When USAID was closed last year, eastern DRC lost about 70% of its humanitarian assistance,” Mangundu said.
This was followed by further funding cuts from other donors, leading to the closure of medical centres, declines in medical supplies and community health workers, and reduced capacity to respond to the outbreak.
“Funding cuts do not directly cause the pandemic, but they weaken the systems that are in place to prevent small crises from becoming larger ones,” Mangundu said.
In Ituri, residents have been repeatedly displaced by the conflict and have had to seek shelter in overcrowded schools and churches with limited access to clean water, sanitation and health care. “Funding cuts exacerbate these existing problems,” he said.
In this setting, he said, it may also be difficult to convince people to adopt safety measures to limit the spread of Ebola. For example, “communities remain connected to their deceased relatives and continue to handle bodies, increasing the risk of transmission.”
Lessons from past outbreaks
Walker said the international response to the current outbreak will determine how it develops.
“The 2018-2020 Ebola response effectively sidelined the local Congolese health system, deeming it too fragile or weak to be an effective partner,” he said. quoting him previous research. The reaction therefore came largely from outsiders to the local communities, leading to suspicion.
“Hopefully,” Walker concluded, “that the international community has learned some hard lessons since the last major outbreak.”
As global health leaders warn that this Its outbreak may increase and affect more countriesMangundu stressed that much more support is needed to end the pandemic in the DRC.
“The country has the capacity to respond, but not enough resources to help control and stop the spread,” he said. “We need to fund humanitarian assistance now and support the people of DRC, before a preventable crisis turns into one with widespread, global consequences.”
This article is for informational purposes only and is not intended to provide medical advice.
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