All secondary cases had direct contact, usually involving blood, with a primary case. Both physicians became infected through accidental skin pricks when drawing blood from patients. A popular science account of this outbreak can be found in Laurie Garrett’s book The Coming Plague. 1975 cases
In 1975, an Australian tourist became infected with MARV in Rhodesia (today Zimbabwe). He died in a hospital in Johannesburg, South Africa. His girlfriend and an attending nurse were subsequently infected with MVD, but survived. 1980 cases
A case of MARV infection occurred in 1980 in Kenya. A French man, who worked as an electrical engineer in a sugar factory in Nzoia (close to Bungoma) at the base of Mount Elgon (which contains Kitum Cave), became infected by unknown means and died on 15 January shortly after admission to Nairobi Hospital. The attending physician contracted MVD, but survived. A popular science account of these cases can be found in Richard Preston’s book The Hot Zone (the French man is referred to under the pseudonym “Charles Monet”, whereas the physician is identified under his real name, Shem Musoke). 1987 case
In 1987, a single lethal case of RAVV infection occurred in a 15-year-old Danish boy, who spent his vacation in Kisumu, Kenya. He had visited Kitum Cave on Mount Elgon prior to travelling to Mombasa, where he developed clinical signs of infection. The boy died after transfer to Nairobi Hospital.
Another risk factor is contact with nonhuman primates, although only one outbreak of MVD (in 1967) was due to contact with infected monkeys.Contrary to Ebola virus disease (EVD), which has been associated with heavy rains after long periods of dry weather, triggering factors for spillover of marburgviruses into the human population have not yet been described. Diagnosis
MVD is clinically indistinguishable from Ebola virus disease (EVD), and it can also easily be confused with many other diseases prevalent in Equatorial Africa, such as other viral hemorrhagic fevers, falciparum malaria, typhoid fever, shigellosis, rickettsial diseases such as typhus, cholera, gram-negative sepsis, borreliosis such as relapsing fever or EHEC enteritis. Other infectious diseases that ought to be included in the differential diagnosis include leptospirosis, scrub typhus, plague, Q fever, candidiasis, histoplasmosis, trypanosomiasis, visceral leishmaniasis, hemorrhagic smallpox, measles, and fulminant viral hepatitis. Non-infectious diseases that can be confused with MVD are acute promyelocytic leukemia, hemolytic uremic syndrome, snake envenomation, clotting factor deficiencies/platelet disorders, thrombotic thrombocytopenic purpura, hereditary hemorrhagic telangiectasia, Kawasaki disease, and even warfarin intoxication. The most important indicator that may lead to the suspicion of MVD at clinical examination is the medical history of the patient, in particular the travel and occupational history (which countries and caves were visited?) and the patients exposure to wildlife (exposure to bats or bat excrements?). MVD can be confirmed by isolation of marburgviruses from or by detection of marburgvirus antigen or genomic or subgenomic RNAs in patient blood or serum samples during the acute phase of MVD.