About haemorrhagic fevers
All viral haemorrhagic fevers, also called VHFs, are caused by a handful of virus families. The illnesses they cause can be spectacularly nasty, including Ebola, Marburg, Lassa fever and yellow fever.
What do they all have in common? They all affect multiple organs, damage blood vessels and throw the body’s ability to regulate itself into chaos. Some of the diseases caused are mild, like the Scandinavian nephropathia epidemica. Others, like Ebola, are deadly more often than not.
You can catch VHFs anywhere in the world, but they’re most often found where the animals that carry them live. Lassa fever, for example, is only found in rural West Africa, carried by local rats and mice.
As an ordinary traveller, the risk is relatively low. But it makes a great deal of sense to avoid areas where there have been outbreaks, especially important when there are no drugs to treat VHFs. All doctors can do is treat the symptoms.
All VHF illnesses come with a fever, as the name implies, and most also come with bleeding disorders. They can all result in shock and many kill.
Five kinds of RNA viruses are responsible
As far as we know so far, all VHFs come from one of five families of RNA virus.
- Lassa fever comes from the Arenaviridae family of viruses, as does Lujo, Machupo, Sabiá and Guanarito
- The Bunyaviridae virus family is responsible for diseases like HFRS, Crimean-Congo haemorrhagic fever and Rift Valley fever
- The Filoviridae virus family includes the horrific Ebola and Marburg
- Flaviviridae viruses lead to dengue, yellow fever and two tick-borne encephalitis illnesses: Omsk haemorrhagic fever and Kyasanur Forest disease
- A newly-discovered Rhabdoviridae virus is probably responsible for two fatal cases of haemorrhagic fever in the Democratic Republic of Congo, proving that we still have a lot to learn about VHFs, where they come from, how they’re carried and how they spread
What are the symptoms of haemorrhagic diseases?
- Increased, uncontrollable, unexplained and unusual bleeding
- A flushed, red face and chest
- Little red or purple spots on the skin
- Unexplained bruising
- Low blood pressure
- Muscle pain, headache, vomiting and diarrhoea
Haemorrhagic disease diagnosis
Because many of the signs and symptoms can easily be mistaken for other diseases, especially in the early stages, a definitive diagnosis is usually only possible through samples diagnosed at a special lab. In general there are fewer white blood cells in infected people, fewer blood platelets, more blood serum liver enzymes and problems with blood clotting.
VHF prevention – how to stay safe from viral haemorrhagic fever
If you’re a regular traveller or holidaymaker, the best way to stay safe from VHFs is to stay away from affected areas altogether. If you work in healthcare or you’re a voluntary worker, it isn’t always that simple. If that’s you, here are some facts to bear in mind:
- With the exception of Yellow fever, there’s no vaccine for VHFs. Medics can only treat the symptoms, not the cause
If you’re an aid worker or healthcare volunteer in an affected area, there are strict VHF isolation guidelines to follow. Everyone except those with dengue should be isolated
- Good hand hygiene, goggles, face shields, doubled-layer gloves, gowns, covers for your shoes and legs are all vital when there’s an outbreak and you’re working with patients
- VHFs can easily spread in hospitals, especially Lassa, CCHF, Ebola and Marburg. If they’re around you’ll need a proven HEPA filter respirator, air-purifying respirator or a positive pressure supplied air respirator if you come within six feet of a patient
- Isolation and special decontamination procedures should be in place