CDC warns doctors to be on the lookout for rare Marburg virus

The Centers for Disease Control and Prevention issued a warning Thursday for clinicians and public health departments in the United States to be on the lookout for cases of a rare Ebola-like virus.

The warning is in response to outbreaks of Marburg virus disease, one in Equatorial Guinea and the other in Tanzania -- with neither country reporting outbreaks before this year.

So far, no cases have been reported in the U.S. nor have any other outbreaks been reported, but the CDC says the warning "provides information about these outbreaks to increase awareness of the risk of imported cases in the United States."

In a press conference on March 21, Tanzania's health minister announced an outbreak among a group of fishermen. Of the eight cases, five were fatal.

Meanwhile, in Equatorial Guinea, there have been 14 confirmed cases since Feb. 7, with 10 of the patients dying, according to the CDC.

Currently there is no evidence that the outbreaks in the two countries are related, and they appear to be independent clusters in which the virus spilled over from animals to humans, the federal health agency said.

Marburg virus disease is a rare illness caused by the Marburg virus, which is a so-called cousin of Ebola virus.

The first cases were identified in European laboratory workers who were handling African green monkeys imported from Uganda.

The virus can spread either from animals to humans or via person-to-person contact either through contact with infected blood or other fluids or objects contaminated with those fluids.

According to the CDC, the incubation period -- the time between infection and onset of symptoms -- can last anywhere from two to 21 days.

A person is not contagious until symptoms appear, which can include sudden fever, headache, fatigue, muscle and joint pain, loss of appetite, gastrointestinal symptoms, or unexplained bleeding.

The CDC says doctors should screen for the disease if someone has symptoms and may have been exposed to the virus while in an affected area -- such as if they attended a funeral or visited a healthcare facility.

The disease can cause serious complications include internal bleeding and organ damage.

"Clinical diagnosis of Marburg virus disease be difficult," the CDC said. "Many of the signs and symptoms of MVD are similar to other infectious diseases (such as malaria or typhoid fever) or viral hemorrhagic fevers that may be endemic in the area (such as Lassa fever or Ebola). This is especially true if only a single case is involved."

There is currently no known treatment for the disease with therapies focused on supportive measures such as balancing fluids, maintaining oxygen levels and blood pressure.

According to the World Health Organization, past outbreaks have had case fatality rates of between 24% and 88% with an average rate of 50%.