Two cases of Marburg virus disease (MVD), a haemorrhagic fever almost as deadly as Ebola, have been recorded in Ghana, the first in the country.
As announced by the authorities, on July 8, blood samples from two people from the Ashanti region (southern) suggested the presence of the Marburg virus and the samples were sent to the Pasteur Institute of Dakar (IDP) for confirmation. the Ghana Health Service (GHS) reported.
"Additional testing carried out at the Senegal IDP has corroborated the results," Patrick Kuma-Aboagye, director general of the GHS, said in a statement on Sunday. "This is the first time Ghana has confirmed the Marburg virus," he added.
Marburg virus disease is transmitted to humans by fruit bats and spreads through direct contact with bodily fluids of infected people, or surfaces and materials, according to the World Health Organization (WHO).
The WHO announced the end of the first Marburg virus outbreak in West Africa in September 2021, 42 days after a single case was identified in Guinea.
Facts about the EVM
• Marburg virus disease (MVD), formerly called Marburg hemorrhagic fever, is serious and often fatal.
• The average fatality rate of the disease is around 50%. During recent outbreaks, these rates have ranged between 24% and 88% depending on the viral strain and the treatment of the cases.
• Rehydration and prompt administration of symptomatic treatment improve survival. The effectiveness of any treatment to neutralize this virus has not been demonstrated, although several immunological, pharmacological and blood product treatments are being developed.
• Although Marburg and Ebola viruses are different viruses, they both belong to the Filoviridae family and cause diseases with similar clinical characteristics. Both are rare, but the fatality rates of their outbreaks can be high.
Transmission
Initially, human EVM infection is due to prolonged stay in mines or caves inhabited by colonies of Rousettus bats.
Transmission between people occurs through direct contact of broken skin or mucous membranes with blood, secretions, organs or other body fluids of infected people, as well as with surfaces and materials contaminated with such fluids, such as personal clothing or bedding.
Cases of transmission to healthcare personnel caring for patients with suspected or confirmed VMD have been reported through close contact without appropriate infection control precautions. Transmission through contaminated injection materials or needle sticks is associated with greater disease severity, faster worsening, and possibly a higher case fatality rate.
This transmission can also occur in funeral ceremonies in which mourners have direct contact with the body of the deceased.
Infectivity persists as long as there is virus in the blood.
Symptoms of EVM
The incubation period (that is, the interval between infection and the appearance of symptoms) ranges from 2 to 21 days.
EVM begins abruptly, with high fever, intense headache and great discomfort, as well as frequent muscle pain. On the third day, severe watery diarrhea, abdominal pain and cramps, nausea and vomiting may appear. Diarrhea may persist for a week. In this phase, it has been described that patients have a “ghost appearance” due to sunken eyes, facial expressionlessness, and extreme lethargy. In the European outbreak in 1967, most patients developed a nonpruritic rash 2 to 7 days after the onset of symptoms.
Many patients have severe hemorrhagic manifestations within 5 to 7 days, and fatal cases usually present some form of hemorrhage, often in multiple organs. The presence of fresh blood in vomit and stool is often accompanied by bleeding from the nose, gums, and vagina. Spontaneous bleeding at venipuncture sites where fluids are administered or blood samples are drawn can be especially problematic. During the severe phase of the disease, patients persistently have high fever. Involvement of the central nervous system can cause confusion, irritability and aggressiveness. Occasional cases of orchitis (inflammation of one or both testicles) have also been described in the late phase of the disease (15 days after its onset).
In fatal cases, death usually occurs 8 or 9 days after the onset of symptoms and is usually preceded by large blood loss and shock.
Diagnosis
Clinically, it can be difficult to distinguish VMD from other infectious diseases such as malaria, typhoid fever, shigellosis, meningitis, and other viral hemorrhagic fevers. To confirm that the cause of the symptoms is the Marburg virus, the following diagnostic methods are used:
•enzymatic immunosorbent assay (ELISA);
•antigen detection tests;
• seroneutralization test;
• reverse transcriptase polymerase chain reaction (RT-PCR);
• electron microscopy; and
• isolation of the virus in a cell culture.
The handling of samples from patients exposes a very high risk and analytical tests of non-inactivated samples must be carried out under conditions of maximum biocontainment. All biological samples for national or international transport must be packaged with the triple packaging system.
Treatments and vaccines
At the moment, no treatments or vaccines have been authorized to combat EVM. However, supportive therapy through oral or intravenous rehydration and treatment of certain symptoms improve survival.
Some monoclonal antibodies in development and certain antivirals that have been used in clinical trials to treat Ebola, such as remdesivir and favipiravir, could also be tested for compassionate or expanded access use as VMD therapy.
In May 2020, the European Medicines Agency granted a marketing authorization to the Zabdeno (Ad26.ZEBOV) and Mvabea (MVA-BN-Filo) vaccines against EVM. The latter contains a virus called Vaccinia Ankara Bavarian Nordic that has been modified to express proteins from the Ebola-Zaire virus and three other viruses from the same group (Filoviridae family). Although this vaccine could protect against VMD, its effectiveness has not yet been proven in clinical trials.
