Illness caused by Marburg virus begins abruptly, with severe headache and severe malaise. Muscle aches and pains are a common feature.
A high fever usually appears on the first day of illness, followed by progressive and rapid debilitation. A severe watery diarrhoea, abdominal pain and cramping, nausea, and vomiting begin about the third day. Diarrhoea can persist for a week. The appearance of patients at this phase has been described as showing “ghost-like” drawn features, deep-set eyes, expressionless faces, and extreme lethargy. In the 1967 European outbreak, a non-itchy rash was a feature noted in most patients between days 2 and 7 after symptom onset.
Many patients develop severe haemorrhagic manifestations between days 5 and 7, and fatal cases usually have some form of bleeding, often from multiple sites. Findings of fresh blood in vomitus and faeces are often accompanied by bleeding from the nose, gums, and vagina. Spontaneous bleeding at venipuncture sites can be particularly troublesome. During the severe phase of illness, patients have sustained high fevers. Involvement of the central nervous system can result in confusion, irritability, and aggression. Orchitis has been reported occasionally in the late phase of disease (day 15).
In fatal cases, death occurs most often between 8 and 9 days after symptom onset, usually preceded by shock.
A History of recorded cases
1967: Germany and Yugoslavia. Marburg haemorrhagic fever was initially detected following simultaneous outbreaks in Marburg and Frankfurt, Germany and Belgrade, former Yugoslavia. The initial cases occurred in laboratory workers handling African green monkeys imported from Uganda. The outbreaks involved 25 primary infections, with 7 deaths, and 6 secondary cases, with no deaths. The primary infections were in laboratory staff exposed to Marburg virus while working with monkeys or their tissues. The secondary cases involved two doctors, a nurse, a post-mortem attendant, and the wife of a veterinarian. All secondary cases had direct contact, usually involving blood, with a primary case. Both doctors became infected through accidental skin pricks when drawing blood from patients.
1975: South Africa, possibly via Zimbabwe. In mid-February 1975, an Australian, aged 20 years, was admitted to a hospital in Johannesburg, South Africa. During early February, he and a companion had travelled extensively through Zimbabwe, often camping outdoors. He died of Marburg haemorrhagic fever four days after hospital admission. His travelling companion became infected, as did a nurse who attended both patients. Both secondary cases recovered.
1980: Kenya. In January 1980, a 56-year-old Frenchman, who had visited Kitum Cave in Kenya’s Mount Elgon National Park, became infected. Despite specialized care in Nairobi and aggressive resuscitation attempts, he died on 15 January. The doctor who attempted resuscitation developed symptoms 9 days later. He recovered.
1987: Kenya. In August 1987, a 15-year old Dane, was admitted to a hospital in Kenya, suffering from Marburg haemorrhagic fever. His illness proved fatal. Nine days prior to symptom onset, he had visited Kitum Cave in Mount Elgon National Park. No further cases were detected.
1998–2000: Democratic Republic of the Congo. The outbreak in DRC marked the first large outbreak of this disease under natural conditions. The outbreak, which occurred from late 1998 to 2000, involved 154 cases, of which 128 were fatal, representing a case fatality of 83%. The majority of cases occurred in young male workers at a gold mine in Durba, in the north-eastern part of the country, which proved to be the epicentre of the outbreak. Cases were subsequently detected in the neighbouring village of Watsa. Family members involved in the close care of patients accounted for some cases, but secondary transmission appeared to be rare. Subsequent virological investigation indicated that virus of several different strains was introduced to human populations, from some yet unknown environmental source, on more than seven separate occasions.
2004–2005: Angola. In what was to become the largest outbreak of MHF in history, this outbreak is believed to have begun in Uige Province in October 2004. By the time the last laboratory-confirmed case was identified in July 2005, the Ministry of Health had reported a total of 374 cases, including 329 deaths (CFR 88%) countrywide. Of these, 368 cases, including 323 deaths, were reported in Uige Province. All cases detected in other provinces have been linked directly to the outbreak in Uige.
2007: Uganda. From June to August 2007, three confirmed cases were reported in mineworkers from Kamwenge, western Uganda. The second and third miners developed illness after caring for their colleague; one of the caregivers died.