Marburg Virus Disease

Marburg virus disease, also known as Marburg hemorrhagic fever, is a severe illness with a high mortality rate. The responsible pathogen, Marburg virus, is a member of the filoviridae family along with the Ebola virus [1]. The first documented outbreak of this disease was in 1967 in Germany and Yugoslavia (which is currently known as Serbia) [2]. Outbreaks have also occurred between 1998 to 2000 in the Democratic Republic of Congo, Angola in 2004 to 2005 [3] [4] and most recently in Uganda in 2012. Additionally, there have been sporadic cases over the years. The African fruit bat acts as a reservoir for this zoonotic virus affecting human as well as non-human primates. The transmission occurs from human to human contact. The incubation period may range from 2 days to 3 weeks [5].

There are three stages of this illness, which are described as the 1) generalization phase, 2) early organ phase, and 3) late organ or convalescence phase [6]. The first phase lasts about 5 days and is characterized by a high fever, headache, chills, malaise, myalgia, and possibly nausea, emesis, watery diarrhea, abdominal pain, pharyngitis, conjunctivitis, and a rash [2] [7] [8]. As the illness progresses, the patient enters the early organ phase, which involves the liver, kidneys, and pancreas. It features neurological symptoms, impaired mental status, hematemesis, bloody diarrhea, and bleeding from other sites [2] [9]. The final phase is critical and often leads to death secondary to critical manifestations such as multiorgan failure, seizures, coagulopathy, cardiovascular collapse, and shock [1].

Physical exam

Assessment of the vital signs typically reveals fever, hypotension and other abnormalities. Also, the patient appears ill and exhibits mental status changes such as confusion, delirium, and dementia [1]. Other notable findings include conjunctival injection, pharyngitis, petechia, ecchymoses, and palatal exanthem. Bleeding from mucosal sites and orifices is observed in severe cases.

Patients presenting with the above symptoms warrant a thorough evaluation consisting of a detailed personal and travel/exposure history, physical exam, and the appropriate studies.

Laboratory tests

A complete blood count (CBC) and complete metabolic panel (CMP) including liver function tests (LFTs) will feature typical findings such as leukopenia, thrombocytopenia, and elevated liver transaminases. Furthermore, a coagulation panel and disseminated intravascular coagulation profile will reveal abnormalities about the patient's critical state.

Diagnostic tests

Viral detection studies such as reverse transcription polymerase chain reaction (RT–PCR) and enzyme-linked immunosorbent assay (ELISA) are the first-line tests [10]. In addition to conventional RT-PCR, quantitative real-time RT-PCR is also used [1] [11].

Other studies such as immunoglobulin (Ig) M and IgG ELISA are used to identify antibodies against the virus [1]. Moreover, IgM–capture ELISAs are commonly performed for the diagnosis of acute disease while IgG antibodies are used retrospectively post-disease [12]. Additionally, there is a promising future for the reverse transcription–loop–mediated isothermal amplification method in diagnosing Marburg virus [13].

There are two other techniques, virus isolation, and electron microscopy, but these are limited to specialized sites [1].

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