New Vaccine Shows Promise In Preventing Fatal Marburg Hemorrhagic Fever
An experimental vaccine being developed by the National Institute of Allergy and Infectious Disease (NIAID), a Center of the National Institutes of Health, continues to show promise as an emergency treatment for accidental exposure to the Marburg virus which causes an infection with a very high fatality rate. Although Marburg hemorrhagic fever is rare in the United States, those at risk include foreign travelers, those in contact with non-human primates, and health care workers.
In a study of rhesus macaques monkeys, 5 out of 6 survived a lethal dose of Marburg virus when treated 24 hours after infection. Two of six survived when treated 48 hours after exposure. Because rhesus monkeys typically succumb to Marburg infection faster than humans, the researchers say that the post-exposure treatment window might be extended further if the vaccine becomes approved for humans.
Marburg virus is a member of the filovirus family, which includes the five species of Ebola virus. It was first recognized in 1967 when simultaneous outbreaks of hemorrhagic fever occurred in laboratories in Germany and Yugoslavia. A total of 31 people fell ill with 7 deaths reported. The original virus came from African green monkeys that were imported to the labs for research for a polio vaccine. Recent scientific evidence implicates the African fruit bat as a reservoir host of the Marburg virus.
Confirmed cases of Marburg hemorrhagic fever primarily have occurred in the African countries of Uganda, Zimbabwe, the Democratic Republic of the Congo, Kenya, and Angola. According to the NIAID, case-fatality rate is between 23-25%. In 2008, the CDC confirmed a case in the US in an American traveler who developed Marburg HF after visiting the well-known “python cave” inhabited by fruit bats at Maramagambo Forest in Queen Elizabeth Park in Western Uganda. He fully recovered from the illness. A Dutch traveler who visited the same cave in 2008 died of Marburg HF.
The onset of Marburg HF is marked by fever, chills, headache, and myalgia about 5-10 days after exposure. After the fifth day of symptoms, a maculopapular rash may occur on the chest, back and stomach. Symptoms become increasingly severe, and may include jaundice, inflammation of the pancreas, severe weight loss, delirium, shock, and multi-organ dysfunction. For those who recover, continued complications from the infection include recurrent hepatitis, or inflammation of the testis, spinal cord, eye or parotid gland.
Travelers in particular should be aware of the risk of acquiring viral hemorrhaging fever and other diseases such as rabies when in contact with animals. Healthcare providers should also be aware of the risk for those who are returning from travel in foreign countries that display symptoms of viral illnesses. Suspected cases should be reported immediately to the state health department as well as to CDC’s Special Pathogens Branch at 404-639-1115.
For More Information about the Marburg and Ebola viruses, read:
Lab Stymied by First Case of Marburg Fever
Scientists Discover How Ebola Virus Infects Cells
Discover of Ebola in Pigs Raises Food Safety Concerns