Marburg virus: forms of contagion, symptoms and treatments

Ghana has triggered a worrying new alert. The country’s health service, after the preliminary discovery of two possible cases in the Ashanti region on July 7 and with the confirmation of tests at the Pasteur Institute in Dakar (Senegal), reported the appearance on its territory of an outbreak of the Marburg virus, the first in the history of Ghana. The patients, two men aged 26 and 51, died, unrelated, and both had symptoms including diarrhea, fever, nausea and vomiting. So far, 98 contacts have been identified and are being monitored and are currently in quarantine.

Marburg virus disease causes severe, often fatal hemorrhagic fever with case fatality rates ranging from 24% to 88% in recent outbreaks. The first major outbreak occurred in Durban, Democratic Republic of Congo in the years 1998 to 2000, and occurred among gold miners and involved 154 cases and 128 deaths (83% case fatality rate). ). The last major outbreak of the disease occurred in 2005 in Angola, when the virus infected 374 people and 329 of them died (88% case fatality rate). The disease has been known since 1967, when two major epidemics occurred simultaneously in the city of Belgrade in Serbia. and in the German cities of Frankfurt and Marburg, from which the virus takes its name.

Marburg virus is a filovirus related to Ebola virus. The disease it causes is usually incurable in humans and in non-human primates, and is characterized by hemorrhagic fever and organ dysfunction, such as liver failure, infection of the spleen, brain, and kidney tissue, and clotting problems throughout the body.

Originally, human infection results from prolonged exposure to mines or caves inhabited by bat colonies of the kind Rousettus. The usual reservoir host species for Marburg virus is the African fruit bat. Rousset the Egyptian although some studies have shown that Sundevall’s bat (Cafe Hipposideros) and other bat species may also act as natural sources of infection.

Fruit bats infected with Marburg virus show no obvious signs of disease, but can transmit the virus to primates, including humans, who develop severe disease with high mortality. In 2008, two separate cases of tourists being infected with the Marburg virus after visiting the same cave were reported. The travellers, a Dutchman and an American, became infected after visiting a cave in a national park in Uganda that was inhabited by colonies of bats. Rousettus. The Dutch tourist died from the infection.

Person-to-person transmission is possible and frequently following close contact with the blood, secretions, organs or other bodily fluids of infected persons. Transmission through infected semen can occur up to seven weeks after clinical recovery.

In Africa, funeral ceremonies in which mourners have direct contact with the body of the deceased may play an important role in the transmission of Marburg virus. Therefore, standard procedures at funeral events include decontaminating the body with a 1:10 bleach solution and placing the deceased in a body bag. The body bag is then closed and the exterior is also decontaminated.

The the incubation period varies from 2 to 21 days. The disease begins abruptly, with high fever, severe headaches and acute malaise. Muscle pain is a common feature. Severe watery diarrhea, abdominal pain and cramps, nausea and vomiting may begin on the third day. Diarrhea may persist for a week. Neurological symptoms (disorientation, agitation, convulsions and coma) may occur in advanced stages of the disease.

Unfortunately, There is still no vaccine against this pathogen or specific treatment for Marburg virus disease, although some candidate vaccines such as cAd3-MARV, vectorized with recombinant chimpanzee adenovirus type 3, are in phase 1 clinical trials. Supportive hospital therapy is currently used, including balancing fluids and electrolytes, maintaining oxygen levels and blood pressure, replacing lost blood and clotting factors, and treating any complications due to infection. Early supportive care improves survival. Survivors of Marburg virus disease have suffered a number of sequelae including exhaustion, myalgia, hyperhidrosis, peeling skin and hair loss.

Emerging infectious diseases significantly affect public health and the global economy, so there is an urgent need to understand the mechanism of transmission between species, and in particular to humans.