Marburg virus has caused outbreaks in two African nations, and healthcare workers should be aware of travel history for incoming patients with classic hemorrhagic fever symptoms, the CDC warned.
The CDC reported recent and possibly ongoing outbreaks of Marburg virus disease (MVD) in Equatorial Guinea and Tanzania. Symptomatic patients who recently traveled to the nations should be placed in isolation precautions that are essentially the same for containing Ebola virus.
“Currently, the risk of MVD in the United States is low; however, clinicians should be aware of the potential for imported cases,” the CDC reported in an April 4 health alert. “MVD should be included as a differential diagnosis for an ill person with history of a concerning exposure while in a MVD-affected area within 21 days before symptom onset.”1
Concerning exposures for travelers could include:
• contact with a symptomatic person with suspected or confirmed MVD;
• visiting or working in a healthcare facility;
• attending or participating in a funeral;
• working in or visiting a mine or cave;
• coming into contact with bats or non-human primates.
No Vaccine or Treatment
There is no approved vaccine or treatment for MVD. The mortality rate is in the range of 23%-90%, depending on the level of supportive care and fluid replacement. The virus does not spread via the airborne route, but can infect contacts via body substances and fomites.
“Marburg virus is spread through contact (through broken skin or mucous membranes) with the blood or other body fluids (including urine, saliva, sweat, feces, vomit, breast milk, amniotic fluid, or semen) of a person who is sick with or has died from MVD, with the body fluids of infected animals, or with needles or other fomites that are contaminated with the virus,” the CDC stated.
A person with MVD is not contagious until symptomatic, with typical signs including fever, headache, muscle and joint pain, fatigue, loss of appetite, gastrointestinal symptoms, or unexplained bleeding, the CDC reported.
Isolation precautions for a symptomatic or “wet” Marburg patient include:2
• impermeable coverall or gown extending to mid-calf;
• powered air purifying respirator or NIOSH-certified N95 respirator. A surgical hood extending to shoulders and a full-face shield should be used with N95;
• boot or shoe covers that extend to at least mid-calf;
• two pairs of gloves, including extended cuffs;
• apron donned over the gown or coverall that covers the torso to mid-calf.
“Currently, there is no evidence to suggest that these two outbreaks are related; most experts agree that these represent two independent animal-to-human spillover events,” the CDC stated.
As of April 4, there were no confirmed cases of MVD related to either outbreak outside the two African nations. The double zoonotic spillover aspect is concerning, as is the fact that MVD seems to be moving beyond its historical range.
“These outbreaks mark the first time that Marburg virus has been identified in either Equatorial Guinea or Tanzania, though the virus has been identified previously in neighboring countries, and the reservoir, the Egyptian fruit bat, is known to be present in both countries,” the CDC noted.
Body substances of infected bats can spread Marburg to humans, and the virus can survive on contaminated fruit.
In February, a cluster of deaths that were later confirmed as MVD were reported in Equatorial Guinea. The index case “presented with fever, vomiting, bloody diarrhea, and convulsions and died the same day.”
“This patient appears to be epidemiologically linked to four deceased community members from one of the affected villages,” the CDC noted. “As of April 5, 2023, 14 laboratory-confirmed MVD cases have been identified from five districts across four provinces in Equatorial Guinea. Ten of these cases were fatal.”
The outbreak in Tanzania was reported on March 21. As of the CDC alert date, there were eight confirmed cases in several villages in the northwest Kagera region. The cases appear to be epidemiologically linked, and resulted in five deaths.
- Centers for Disease Control and Prevention. Marburg virus disease outbreaks in Equatorial Guinea and Tanzania. April 6, 2023.
- National Emerging Special Pathogens Training and Education Center. Infection prevention and control measures for Marburg virus disease. March 3, 2023.