Hemorrhagic fever syndromes

The term "viral haemorrhagic fevers" (VHF) or "haemorrhagic fever syndromes" covers a heterogeneous group of major viral infections that are of interest to the public and health authorities worldwide. These are almost exclusively viral infections of the tropics and subtropics, with varying degrees of infestation of the population. Clinically, there is often a combination of unspecific flu symptoms, which can be caused by the symptoms:

• fever with unspecific general symptoms
• Vascular permeability and blood coagulation disorders with hemorrhagic diathesis of varying severity
• possible hypovolemic shock and multiple organ failure.

viral haemorrhagic fever

Virus Virus family Vectors Geographical distribution Designation

Marburg virus Filoviridae/ bats / Africa/Marburghemorrhagic fever

Ebola Virus Filoviridae/bats (?) / Africa/Ebola Hemorrhagic fever

Lassa virus Arenaviridae/ rodents/ West Africa/ Lassa fever

Lujo virus Arenaviridae/ Rodents (?)/ Southern Africa/Lujo hemorrhagicfever

Machupo virus Arenaviridae/ rodents/ Bolivia/Bolivianhaemorrhagic fever

Junin virus Arenaviridae/ rodents/ Arg./Argentinehemorrhagic fever

Guanarito virus Arenaviridae/rodents/Venez./Venezuelanhaemorrhag. Fever

Sabia virus Arenaviridae/virus. ?/Brazil/Brazilianhaemorrhagic fever

Chapare-Virus Arenaviridae/carriers ?/Bolivia /Anden Haemorrhagic fever

LCM Arenaviridae/ mouse/worldwide /Lymphocyticchoriomeningitis

Yellow fever virus Flaviviridae/ mosquitoes/ Africa, South America/ yellow fever

Dengue virus Flaviviridae/biting mosquitoes/tropicals worldwide/Denguehaemorrhag. Fever

Omsk Haem. fever virus Flaviviridae/ ticks/ Russia /OmskHaemorrhagic fever

Kyasanur forest virus Flaviviridae/ ticks/ India/Kyasanur forest disease

Alkhumra virus Flavivir1idae/Ticks (?)/Arabia, Egypt/Arabic Haemorrhagic fever

Rift Valley Virus Bunyaviridae/ Mosquitoes/Africa/ Rift Valley Fever

Crimean-Congo-HFV Bunyaviridae/Ticks/Africa, Asia, Eur./Crimean-Congo haemorrhag. fever

Huaiyangshan Virus Bunyaviridae/ ticks/China Huaiyangshan fever

Garissa virus Bunyaviridae /birds/ Africa/ Garissa fever

Puumala virus Bunyaviridae/rodents/Eur. Asia/HaemorrhagFever+Ren. Symptoms

Hantaan Virus Bunyaviridae / rodents/Asia/Korean Haemorrhagic fever

Dobrava virus Bunyaviridae/rodents/Europe/Balkan Haemorrhagic fever

The natural hosts of the viruses are rodents, mosquitoes or ticks, which are mainly spread in tropical and subtropical regions. A human-to-human transmission is possible with various virus infections (e.g. Ebola virus, Lassa virus), which is why viral haemorrhagic fever diseases can occasionally occur as imported infections in Europe.

Yellow fever has been known as a haemorrhagic disease for centuries. It is believed to have been present in China as far back as 1000 years ago.

Other diseases of this type, such as Rift Valley Fever, Marburg Virus Disease, Ebola and Lassa Fever and Dengue Hemorrhagic Fever have been recognized as independent diseases for several decades. It is true that VHF are not as important for the total population of a region or state as measles or the recently feared corona virus diseases (epidemic 2019/2020). However, these infections cause unfamiliar problems for health authorities in many countries due to their dreaded lethality and the difficulties in health management.

In fact, these tropical diseases belong to the zoonoses. They are transmitted by arthropods, rodents or through direct contact. Humans are often the final link in an infection chain. Vertebrates are usually the reservoir. Certain mammals act as amplifiers of the virus circulation (so-called amplifying hosts), such as monkeys in yellow fever or domestic ruminants such as Rif Valley Fever and Kyasanur Forest Disease. In Crimean-Congo fever, ticks are both vectors and reservoir.

The complex relationships between the transmission of these diseases and their integration into specific biotopes and ecosystems explains their limited geographical distribution.

The Ebola virus repeatedly causes a great stir in the media, and its example clearly shows that even in our latitudes, precise knowledge of how to deal with travel-associated infectious diseases is necessary in order to counteract the spread of the virus through targeted measures.

The pathogens of VHF have a special tropism towards capillary endothelia. Their damage causes increased vascular permeability, whereby complement activation with the formation of immune complexes via vasculitic processes contributes to an increased general tendency to bleed.

This leads to hypovolemia, tissue hypoxia, acidosis, hyperkalemia, vomiting, dehydration and possible irreversible shock. Intravascular blood clotting can further increase the bleeding tendency.

Pharyngitis, vomiting, diarrhoea, abdominal pain, haemorrhagic diathesis with bleeding tendencies in skin and mucous membranes

A quick diagnosis is extremely important because it is crucial for further management.

On a case-by-case basis, the extent to which contact persons or suspected cases must be kept in quarantine must be examined. Furthermore, transport problems have to be solved, as local supply possibilities are often absolutely insufficient.

It cannot be avoided that sick persons return home by plane during the incubation period or in the uncharacteristic prodromal stage.

Knowledge of the incubation period, the period of infectivity and a general knowledge of the possibilities of introduction of these tropical diseases are therefore of great importance for medical personnel.

The dangerous nature of VHF requires a consistent approach right from the start:

• Taking a correct anamnesis
• Origin
• Travel activities of the last 4 weeks
• Contact possibilities with patients or their secretions
• Contact possibilities with animals
• Fever Reactions

Malaria, leptospirosis, sepsis, intoxications (e.g. food poisoning by Enterobacter or Staphylococci)

Cases of suspicion must be reported. Furthermore the RKI in Berlin should be informed.

Only for yellow fever there are "International Health Regulations"!