Marburg Virus

Marburg Virus (MARV) is a fatal virus that causes viral Marburg viral disease (MDV) in human beings and primates. Although not as deadly as filoviruses, a virus which shares the same family with MARV, it is highly contagious and can lead to death. The virus was first observed in cases on human attacks in Marburg and Frankfurt in Germany, hence its name. In 2004-2005, the most fatal attacks were recorded in Angola, whereby approximately 140 people lost their lives. This essay shall review the virus’ epidemiology, etiologic agents, pathogenesis, and clinical symptoms. In addition, an analysis will be conducted on management and prognosis techniques as well as prevention and control.

1. Epidemiology

In 1967, the first known cases of Marburg hemorrhagic fever were recorded in Germany and Serbia. Researchers and medical practitioners came to the conclusion that the primary cause of infection was due to the continued exposure by patients to blood and tissue from green monkeys originally imported from Uganda for carrying out laboratory tests for the pharmaceutical industry. Later cases have justified this conclusion since most of these outbreaks have occurred around Lake Victoria in countries such as Kenya, Uganda and the Democratic Republic of Congo with a few exceptional cases in South Africa, Zimbabwe and Angola. Although the 2004/2005 MARV outbreak in Zimbabwe and Angola was a surprise, scientists have pointed out that these regions are part of the larger Central, East and Southern Africa, an area that enjoys almost similar ecological conditions as the identified endemic Lake Victoria region (Schwartz, 2009).

The Democratic Republic of Congo’s Dubra-Watsa outbreaks in the period of 1998-2000 have been found as largely emanating from an abandoned gold mine. The mine provided optimal breeding grounds which led to the introduction of several genetically distinct viral strains. Fortunately, heavy tropical rains led to the flooding of the mine, hence destroying the breeding site. MARV poses a serious threat to the public, especially given the fact that the virus can be imported to other continents. Recent attacks in the Netherlands and United States signify the need for the formulation of suitable countermeasures as well as research on diagnosis and treatment (Mehedi, Groseth, Feldmann & Ebihara, 2011).

1. Etiologic Agents

MARV’s etiological agents have not yet been fully ascertained. Although African green monkeys have been held liable for previous outbreaks in Germany, these studies have not been conclusive. In addition, vervet monkeys have been found to aid in the transmission of the Marburg virus. However, there is no conclusive research that identifies them as a large natural reservoir for the virus. Other detailed studies on other animals and insects have not presented any positive evidence.

However, there is a high probability that among specimens of rodents, arthropods and other animals under investigation, one or more of these species may be responsible for transmitting the MARV and Ebola virus. Conclusive investigations identified the multi-mammate rat, which is a peridomestic rodent, as a natural reservoir as well as a vector for the African Lassa fever. Other findings indicate that rodents serve as vectors for Bolivian and Argentine hemorrhagic fevers. Therefore, there is a strong likelihood that rodents and monkeys contain reservoirs of these viruses (MARV and Ebola viruses) and also act as vectors in the transmittance of the viruses (Simpson, 1977).

1. Pathogenesis

MARV’s lifecycle commences with virion attachment followed by fusion with cell membranes. Once inside the cell, it transcribes its genes into mRNAs, a stage that is followed by replication. Newly synthesized genomes and structural proteins assemble and break out of the cell, hence destroying it. They then attack other cells and repeat the cycle (Bray, 2011).

1. Clinical Manifestations

The incubation period may range from 3 to 21 days during which there are little or no medical signs or symptoms. However, once the incubation period is over, the patient experiences various vital symptoms. First, one experiences abrupt and severe headache (frontal and temporal) in addition to experiencing malaise, arthralgia, chills, myalgia, fever and chest pains. As the disease progresses, the patient experiences nausea accompanied by diarrhea, anorexia, vomiting and severe abdominal pain. Soon afterwards, the patient experiences difficulties in breathing characterized by various respiratory tract infections such as sore throat, dyspnea, coughing and pharyngitis. If left unattended, the patient’s central nervous system is affected which is reflected by confusion, depression, fatigue, seizures and severe headaches which culminate into a comma.

Acute signs include hemorrhagic symptoms such as melena, hematemesis and bleeding in gastrointestinal tracts, nose and other mucous membranes. However, the net loss of blood is not substantial and is therefore not the cause of death. Patients succumb to death due to several conditions such as hypertension, fluid redistribution and focal tissue necroses which lead to multiple organ dysfunction syndrome (Ashworth, 1995).

1. Management and Prognosis

Marburg viral disease (MVD) is indistinguishable from a number of diseases such as Ebola viral disease, viral hemorrhagic fevers and typhoid fever. Therefore, medical practitioners ought to take into account the patient’s medical history, such as recent travel and occupational trends. This may include areas visited and probable exposure to wildlife. Blood or serum samples should be obtained and laboratory tests taken in order to determine whether the MARV virus is present in the patient.

Prognosis has been generally poor in most documented cases. Recovery may be either complete or protracted. In the latter case, conditions such as parotitis, hepatitis and orchitis may persist despite medical treatment. In some cases, the Marburg virus has been known to reactivate in future, causing a severe subsequent infection. In addition, rare cases of transmittance through sperms have been recorded. However, MARV infection cases in children are rare. Therefore, adequate measures need to be taken in order to reduce the high fatality rates (Ashworth, 1995).

1. Prevention and Treatment

Despite the fact that research has been conducted on the MARV disease for close to four decades, a vaccine has not yet been developed. In addition, there is no known effective anti-MARV disease therapy. All treatment procedures primarily focus on minimizing clinical symptoms and treating secondary infections. Therefore, there is a need to observe several preventative measures as well as formulate policies in order to manage disease outbreaks.

Various strategies have been advocated in order to curb the spread of this contagious virus. First, travelers intending to travel to endemic areas should visit informative websites such as the Center for Disease Control in order to identify any potentially harmful diseases as well as learn about prevention strategies. Secondly, one should wash his/her hands frequently. Like any other contagious disease, washing hands with soap and water keeps such diseases at bay. Thirdly, governments and health institutions isolate and quarantine known cases of the MARV disease. Hence, this prevents the spread of the disease and ensures few people loose their lives to MARV. In addition, health workers and medical practitioners, those working in endemic areas are advised to follow infection-control protocols. They should wear protective clothing such as masks, hand gloves, eye shields and gowns which shield them from direct contact with their patients. Furthermore, all instruments used in health centers and medical institutions should be properly sterilized and carefully disposed after use. Needles, syringes and scalpels, if poorly disposed, may lead to a vast outbreak in a certain locality. Finally, unauthorized personnel should not handle those who have succumbed to the disease. This is due to the fact that the remains of these victims are highly contagious and would thus result in an outbreak (Bausch, Sprecher, Jeffs & Boumandouki, 2008).