Marburg is a rare but highly infectious viral hemorrhagic fever and is in the same family as Ebola, a better-known virus that has plagued West Africa for years.
The Marburg virus is a “genetically unique zoonotic … RNA virus of the filovirus family,” according to the Centers for Disease Control and Prevention. “The six species of Ebola virus are the only other known members of the filovirus family.”
Fatality rates range from 24 percent to 88 percent, according to the WHO, depending on the virus strain and quality of case management.
Marburg has probably been transmitted to people from African fruit bats as a result of prolonged exposure from people working in mines and caves that have Rousettus bat colonies. It is not an airborne disease.
Once someone is infected, the virus can spread easily between humans through direct contact with the bodily fluids of infected people such as blood, saliva or urine, as well as on surfaces and materials. Relatives and health workers remain most vulnerable alongside patients, and bodies can remain contagious at burial.
The first cases of the virus were identified in Europe in 1967. Two large outbreaks in Marburg and Frankfurt in Germany, and in Belgrade, Serbia, led to the initial recognition of the disease. At least seven deaths were reported in that outbreak, with the first people infected having been exposed to Ugandan imported African green monkeys or their tissue while conducting lab research, the CDC said.
Where has Marburg been detected?
The Ghana cases are only the second time Marburg has been detected in West Africa. The first reported case in the region was in Guinea last year. The virus can spread quickly. More than 90 contacts, including health workers and community members, are being monitored in Ghana. The WHO said it has also reached out to neighboring high-risk countries to put them on alert.
Cases of Marburg have previously been reported elsewhere in Africa, including in Uganda, the Democratic Republic of Congo, Kenya, South Africa and Zimbabwe. The largest outbreak killed more than 200 people in Angola in 2005.
The virus is not known to be native to other continents, such as North America, and the CDC says cases outside Africa are “infrequent.” In 2008, however, a Dutch woman died of Marburg disease after visiting Uganda. An American tourist also contracted the disease after a Uganda trip in 2008 but recovered. Both travelers had visited a well-known cave inhabited by fruit bats in a national park.
What are the symptoms?
The illness begins “abruptly,” according to the WHO, with a high fever, severe headache and malaise. Muscle aches and cramping pains are also common features.
In Ghana, the two unrelated individuals who died experienced symptoms such as diarrhea, fever, nausea and vomiting. One case was a 26-year-old man who checked into a hospital on June 26 and died a day later. The second was a 51-year-old man who went to a hospital on June 28 and died the same day, the WHO said.
In fatal cases, death usually occurs between eight and nine days after onset of the disease and is preceded by severe blood loss and hemorrhaging, and multi-organ dysfunction.
The CDC has also noted that around day five, a non-itchy rash on the chest, back or stomach may occur. Clinical diagnosis of Marburg “can be difficult,” it says, with many of the symptoms similar to other infectious diseases such as malaria or typhoid fever.
Can Marburg be treated?
There are no vaccines or antiviral treatments approved to treat the Marburg virus.
However, supportive care can improve survival rates such as rehydration with oral or intravenous fluids, maintaining oxygen levels, using drug therapies and treating specific symptoms as they arise. Some health experts say drugs similar to those used for Ebola could be effective.
Some “experimental treatments” for Marburg have been tested in animals but have never been tried in humans, the CDC said.
Virus samples collected from patients to study are an “extreme biohazard risk,” the WHO says, and laboratory testing should be conducted under “maximum biological containment conditions.”
Anything else to know?
The WHO said this week it is supporting a “joint national investigative team” in Ghana and deploying its own experts to the country. It is also sending personal protective equipment, bolstering disease surveillance and tracing contacts in response to the handful of cases.
More details are likely to be shared at a WHO Africa online briefing scheduled for Thursday.
“It is a worry that the geographical range of this viral infection appears to have spread. This is a very serious infection with a high mortality rate,” international public health expert and professor Jimmy Whitworth of the London School of Hygiene and Tropical Medicine told The Washington Post on Monday.
“It is important to try to understand how the virus got into the human population to cause this outbreak and to stop any further cases. At present, the risk of spread of the outbreak outside of Ashanti region of Ghana is very low,” he added.