Viral Hemorrhagic Fever: Causes

Pathogenesis (disease development)

Pathogenesis depends on the type of pathogen. Pathogens are transmitted as follows: see below.

Etiology (causes)

Chikungunya virus (CHIKV).

  • Transmission by mosquitoes, especially Aedes species.
  • Transmission from warm-blooded animals to warm-blooded animals (rodents, primates, etc.).

Dengue virus (DENV)

  • Transmission by mosquitoes, mainly Aedes species (especially Aedes aegypti, furthermore Aedes albopictus).

Ebola virus (EBOV)/Marburg virus (MARV).

  • Pathogen reservoir are the flying foxes or bats living in sub-Saharan Africa.
  • Transmitters are non-human primates, rodents as well as fruit bats. Through contact with infected animals, the disease is transmitted to humans. Transmission (route of infection) from person to person occurs through contact infection (with blood or other fluids of the diseased person or the deceased) – primarily medical personnel, laboratory personnel

Yellow fever (GFV)

  • Mosquitoes of the genera Aedes and Haemagogus. The former are diurnal and nocturnal.
  • In exceptional cases, transmission through blood donations is possible.

Crimean-Congo virus (CCHF)

  • Pathogen reservoir are cattle, sheep, camels rodents, birds and herbivores.
  • Transmission by ticks (Hyalomma); also through contact with contaminated meat or blood – medical personnel, agricultural workers, forest/forestry workers, campers.

Lassa virus (LV)

  • Pathogen reservoir are rodents, especially rats of the species Mastomys natalensis (multigizzled rat).
  • Transmission by contaminated feces, urine, blood → via respiratory tract, food, skin lesions; nosocomial infections and laboratory infections common.

Rift valley virus (RVF, English Rift valley fever).

  • Pathogen reservoir are ruminants, mosquitoes.
  • Transmission by mosquitoes (Aedes, Culex); contact with contaminated blood, tissue, feces, aerosols, consumption of contaminated meat, dairy products; nosocomial infection – veterinarians, butchers, longshoremen, herders, livestock owners.

West Nile fever virus (WNV).

  • The main reservoir of the pathogen are wild birds
  • Transmission by mosquitoes (different mosquito species, in Europe mainly Culex pipiens and modestus).