Marburg virus: All your questions about the deadly disease outbreak answered

Rwanda is facing its first Marburg virus outbreak. Starting from late September, As of October 17, 62 cases and 15 deaths have been reportedmainly medical staff in the capital Kigali.

In order to detect infections early and prevent further spread, we have conducted contact tracing of more than 800 infected people, two of whom have traveled to Belgium and Germany but have since given the all-clear. As of October 21, No new cases or deaths reported in six daysBut the threat of an outbreak has not gone away.

What is Marburg virus? What are its symptoms?

Marburg virus belongs to the same family of viruses as the virus that causes Ebola, “one of the deadliest pathogens known to infect humans,” opinion article based on new england journal of medicine.

They can cause similar symptoms, such as fever, chills, headache, and muscle aches. Within a few days, people may develop a rash on their chest, back, and abdomen. They may also experience nausea, vomiting, and diarrhea.

Marburg virus damages blood vessels and disrupts clottingwhich can cause blood in vomit and stool, as well as bleeding from the nose and gums. In extreme cases, the infection can lead to internal bleeding and sepsis, which can lead to organ failure and death.

Where do outbreaks usually occur?

The virus was first discovered in 1967 following outbreaks in the German cities of Marburg and Frankfurt and the Serbian capital, Belgrade. The cases are linked to laboratory experiments to improve the polio vaccine, involving African green monkeys (Ethiopian green algae) from Uganda.

Since then, the virus has typically caused several outbreaks every decade, often in East African countries such as Uganda and neighboring Democratic Republic of Congo (DRC) in Central Africa.

The virus was discovered in Guinea, West Africa, in 2021. Since then, the virus has broken out in different parts of the continent every year. For example, Ghana had its first outbreak in 2022, and Equatorial Guinea had its first case last year. Egyptian fruit bat (Egyptian brown bat) living in different parts of Africa and may carry Marburg virus, says Emma Thomson at the University of Glasgow, UK.

Exactly why outbreaks appear to be occurring more frequently is unclear. Thomson said this could be due to improved case surveillance and more frequent exposure of people to Egyptian fruit bats. Miles Carroll Professors at Oxford University think so too.

People can be infected with Marburg virus If they visit caves where bats live or work in mines. Carroll said this is likely to happen more, but increased deforestation also brings people closer to the animals.

How deadly is it?

Marburg virus mortality rates vary widely 24% to 88% In past outbreaks, with Ebola virus mortality rate is 25% to 90%.

Thomson said the difference in death rates may be due to differences in countries’ ability to detect cases and their hospital resources.

On October 20, Director-General of the World Health Organization Tedros Adhanom Ghebreyesus issued a statement saying that the agency Level of intensive care received by patients in Rwanda. He mentioned two people with multi-organ failure who were on life support and receiving mechanical ventilation. “We believe this is the first time a patient with Marburg virus has been extubated in Africa,” he said. “These patients may have died in previous outbreaks.”

The ongoing outbreak in Rwanda is the third largest to date in terms of both cases and deaths. It was behind the outbreak in the Democratic Republic of Congo from 1998 to 2000, At that time, 154 cases and 128 deaths were recordedand the 2004-2005 outbreak in Angola, when 252 people were infected and 227 died.

Who is most at risk?

Thomson said there have been relatively few known cases of Marburg since its discovery, making it difficult to know who is most likely to be severely infected. But she said those with suppressed immune systems, such as the elderly or pregnant women, may be more vulnerable.

Few cases have been reported during pregnancy, but the European Center for Disease Prevention and Control Says infections are usually more serious during pregnancywhen immune function is altered anyway.

Ebola virus too More severe in older peopleso the same may be true for Marburg virus, Thomson said.

How do you catch it?

Rwanda’s health minister said genetic sequencing of Rwandan cases showed the virus had jumped to humans only once during the current outbreak from animals such as Egyptian fruit bats or African green monkeys. Tweet October 20th.

Therefore, the remaining transmission occurs from person to person. This occurs if virus particles in someone’s blood or other body fluids enter the body of another person through broken skin or through the eyes, nose, or mouth. People touching the bodies of infected people during burial ceremonies also increases the risk of transmission.

Carroll said there is no evidence that Marburg virus spreads through droplets expelled when an infected person breathes, talks, coughs or sneezes.

How to treat?

There are no drugs approved specifically to treat Marburg virus. People who require hospitalization often receive intravenous fluids to replace fluids lost through vomiting and diarrhea. Painkillers can also help relieve discomfort.

In 2021, researchers discovered that combining the antiviral drug remdesivir with antiviral antibodies Protects four out of five rhesus monkeys from lethal doses of infection. October 15, Rwanda begins testing this approach in humans.

Is there a vaccine?

There is currently no approved vaccine for Marburg virus, but researchers are testing one Experiment 1 In Rwanda, 1,700 doses of vaccine delivered As of October 14, 669 doses of vaccine have been administered.

The vaccine is a single shot containing engineered genetic sequences from an adenovirus that causes cold-like symptoms. The researchers tweaked the adenovirus to contain proteins used by the Marburg virus to infect cells. Once injected, the adenovirus enters cells and produces copies of the viral protein so the immune system can learn to recognize it.

Thomson said vaccinating the contacts of an infected person may be the most effective use of vaccine doses in slowing the spread of the virus.

What are the risks of this epidemic leaving Rwanda?

Carroll said Rwanda has increased testing of contacts of infected people in quarantine, but the possibility of virus spread remains.

“The potential for localized spread in the region to neighboring countries is currently very concerning,” Thomson said. Rwanda borders Uganda, Tanzania, Burundi and the Democratic Republic of Congo. She said the virus could also spread further afield in Africa and even cause sporadic cases elsewhere in the world if people traveled to those areas.

Early October, After a platform at Hamburg train station was blocked Two passengers with suspected Marburg symptoms who had recently visited Rwanda were traveling on a train from Frankfurt. It was later confirmed that they did not have the virus.

Carroll said countries needed to warn people coming from Rwanda about the risks and signs of infection in Marburg. If someone develops symptoms, they can be quickly screened and quarantined before an outbreak occurs elsewhere, he said.