FROM EBOLA TO MARBURG : IT IS A SEASON OF DEADLY VIRUSES

With West Africa, and indeed the rest of the world, still reeling from the deaths brought about by the Ebola virus, the recent death of a Ugandan hospital technician of another deadly viral disease, Marburg Haemorrhagic Fever (MHF), has brought fresh fears.Uganda’s Ministry of Health disclosed that a total of 99 people who had been in contact with the victim had been moved to quarantine. These contacts are being monitored for signs and symptoms of the disease after tests confirmed that the 30-year-old man
who worked as a radiographer in a Kampala hospital died of the disease. The man was said to have had a headache, abdominal pains, diarrhoea and vomited blood before he died.
Marburg virus was first identified in 1967, after simultaneous outbreaks in Marburg (from which the disease takes its name) and Frankfurt both in Germany, Belgrade, Serbia and Yugoslavia. It was later traced back to monkeys imported from Uganda for laboratory work. Since then, the virus has appeared sporadically, with just a dozen outbreaks on record. The most recent outbreak, also in Uganda, in 2012, killed four out of 15 patients, according to the United States of America’s Centers for Disease Control and Prevention.

The Marburg virus is similar to the Ebola virus in many ways than one. They both cause illnesses marked by severe bleeding (haemorrhage), organ failure and, in many cases, death. The Marburg virus is a genetically unique zoonotic (transmissible from animal to man) RNA virus of the filovirus family. The five species of Ebola virus are the only other known members of the filovirus family. The reservoir host of Marburg virus is the African fruit bat which, when infected with the virus, do not to show obvious signs of illness.

Although, it is not clearly known of how the Marburg virus first got transmitted from its animal host to humans, it was discovered that in the two cases in Uganda in 2008, unprotected contact with infected bat faeces or aerosols were the most likely routes of infection. In some other outbreaks, persons who have handled infected non-human primates or have come in direct contact with their fluids or cell cultures have become infected. As soon as infection occurs, it leads to contracting the deadly Marburg Haemorrhagic Fever which has a high mortality.

Human-to-human transmission occurs within communities through cultural practices, under-protected family care settings and under-protected health care staff. Just like the Ebola virus, close contact with the blood, secretions or other bodily fluids of infected persons, burial ceremonies where mourners have direct contact with the body of the deceased and  close contact without the use of correct infection control precautions by health workers can play a significant role in the transmission of the Marburg virus. Transmission can also occur through infected semen for up to seven weeks after clinical recovery. Transmission has not been established to be air borne or by insect bites. According to the World Health Organisation, case fatality rates in Marburg Haemorrhagic Fever outbreaks have ranged from 24 per cent to 88 per cent.

The incubation period (period from infection to beginning of symptoms appearing) varies from two to 21 days.

The World Health Organisation states that symptoms of Marburg haemorrhagic fever begin abruptly with high fever, severe headache, muscle aches and pains as well as severe general feeling of unwellness. Severe watery diarrhoea, abdominal pain and cramping, nausea and vomiting usually begin on the third day. The diarrhoea can persist for a week. The looks of patients at this phase also change drastically as it has been reported that they show “ghost-like” drawn features, deep-set eyes, expressionless faces, and extreme lethargy. Sometimes, a non-itchy rash may be noted in patients between two and seven days after onset of symptoms.

As the name implies, there is haemorrhaging (bleeding) at some point. Many patients develop severe haemorrhagic manifestations between five and seven days, and fatal cases usually have some form of bleeding, often from multiple areas. Fresh blood in vomitus and faeces is often accompanied by bleeding from the nose, ears, vagina and other orifices. Spontaneous bleeding also occurs at sites where intravenous access is obtained to give fluids or obtain blood samples. During the severe phase of illness, patients have sustained high fever and there is an involvement of the central nervous system which can result in confusion, irritability, and aggression

Death occurs most often between eight and nine days after the onset of these symptoms and is usually preceded by severe blood loss and shock.

Unfortunately, it neither has any vaccine or specific treatment at the moment. Treatment includes intensive supportive care, as patients are frequently in need of intravenous fluids or oral rehydration with solutions containing electrolytes.

Over the years, there have been several attempts at creating a vaccine and these are being tested but it could be several years before any are available.

With the recorded death in Uganda, the fear of a possible spread within and outside the country is palpable. However, Uganda, which is no stranger to haemorrhagic fevers such as Ebola and Marburg and has lived with outbreaks of these deadly diseases for decades including an outbreak of Ebola in 2000 that killed at least 224 people over several weeks, seems confident of containing the spread of the virus. Ugandan health officials have tried to assuage the mounting fears  of a spread by stating that they can contain an outbreak by drawing on their past experience in fighting Ebola and the Marburg haemorrhagic fever.

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