MARBURG AND EBOLA VIRAL DISEASE
In 1967 a severe infectious illness broke out among laboratory workers in Marburg, West Germany, who had handled tissues from a batch of vervet monkeys imported from Uganda.In 1976 outbreaks of the disease occurred in Sudan and Zaira from a focus on the Ebola River. The viruses causing these two outbreaks were structurally identical but antigenically distinct. In 1995 a further outbreak of Ebola disease occurred in Zaire with a 77% mortality. It is believed there is an unknown animal reservoir from which virus can be transmitted to primates and humans. Sporadic cases have occurred elsewhere in Africa. In person-to-person outbreaks the mortality is high, but successive human passage seems to reduce virulence. The incubation period is 5-9 days.
The illness presents suddenly with fever, severe myalgia and diarrhoea, followed by pharyngitis, generalised erythematous rash and lymphadenopathy. Fatal complications include haemorrhage, secondary infection, encephalitis, renal failure and pneumonia.
OTHER HAEMORRHAGIC FEVERS
The term 'haemorrhagic fevers', while popular, covers too broad a field of diseases to be of great value. Hence,in addition to the different families of viruses which cause haemorrhagic fever, covered in this chapter and other non-viral infections are associated with haemorrhagic features, as listed in the information box.
CAUSES OF HAEMORRHAGIC FEVERS |
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Viruses |
Rickettsiae |
Rocky Mountain spotted fever |
Bacteria |
|
Spirochaetes |
Relapsing fever |
Protozoa |
African trypanosomiasis |