THE World Health Organisation (WHO) has not ruled out the possibility of the Marburg virus disease (MVD) becoming a global health pandemic if necessary precautions are not taken on time.
By Michael Gwarisa
According to the Africa Center for Disease Control, MVD is a highly fatal, zoonotic haemorrhagic disease caused by the Marburg virus. Human-to-human transmission occurs through direct contact with body fluids from infected persons, or contact with equipment and other materials contaminated with infectious blood or tissues, body fluids of infected people, and contaminated surfaces or materials.
Giving the situtaional analysis of the MVD, the WHO said at the moment there was high risk of spread of the disease in laces where it has already been reported.
WHO assesses the risk posed by the outbreak as very high at the national level, moderate at the regional level, and low at the global level,” said WHO.
The first Disease Outbreak News on the MVD was published on 25 February 2023, eight additional laboratory-confirmed cases of Marburg virus disease (MVD) have been reported in Equatorial Guinea. The disease has also been recorded and reported in the Republic of Tanzania in Bukoba district, Kagera region, north western Tanzania.
In Tanzania, cumulatively, eight confirmed cases and five deaths, including a health care worker have been reported (case fatality rate: 63%), while three are undergoing treatment at designated treatment centres. Cases presented with fever, vomiting and bleeding from different body orifices. Samples collected tested positive by polymerase chain reaction (PCR) at the National Public Health Laboratory.
WHO says Marburg virus and the closely related Ravn virus are the causative agents of Marburg virus disease, which has a case-fatality ratio of up to 88%. Marburg virus disease was initially detected in 1967 after simultaneous outbreaks in Marburg and Frankfurt in Germany, and in Belgrade, Serbia. Rousettus aegyptiacus fruit bats are considered natural hosts for Marburg virus, from which the virus is then transmitted to people.
Marburg spreads between people via direct contact through broken skin or mucous membranes with the blood, secretions, organs or other bodily fluids of infected people, and with surfaces and materials such as bedding, clothing contaminated with these fluids. Healthcare workers have previously been infected while treating patients with suspected or confirmed MVD. Burial ceremonies that involve direct contact with the body of the deceased can also contribute to the transmission of Marburg.
The incubation period varies from two to 21 days. Illness caused by Marburg virus begins abruptly, with high fever, severe headache, and severe malaise. Severe watery diarrhoea, abdominal pain and cramping, nausea, and vomiting can begin on the third day. Severe haemorrhagic manifestations may appear between five and seven days from symptom onset, and fatal cases usually have some form of bleeding, often from multiple areas. In fatal cases, death occurs most often between eight and nine days after symptom onset, usually preceded by severe blood loss and shock.
In the early course of the disease, the clinical diagnosis of MVD is difficult to distinguish from many other tropical febrile illnesses due to the similarities in the clinical symptoms. Other viral haemorrhagic fevers need to be excluded, including Ebola virus disease, as well as malaria, typhoid fever, leptospirosis, rickettsial infections, and plague.
Laboratory confirmation is primarily made by RT-PCR. Other tests can be used such as antibody-capture enzyme-linked immunosorbent assay (ELISA), antigen-capture detection tests, serum neutralization test, electron microscopy, and virus isolation by cell culture.
Although no vaccines or antiviral treatments are approved to treat the virus, supportive care – rehydration with oral or intravenous fluids – and treatment of specific symptoms improve survival. A range of potential treatments are being evaluated, including blood products, immune therapies, and drug therapies.