Ebola is not the only virus known to cause hemorrhagic fever and it is certainly not the most common. This page serves to list many of the common viral hemorrhagic fevers (VHF) in a table with brief descriptions for reference. The diseases listed are those commonly found in humans and excludes those which effect animals such as rabbit hemorrhagic disease.
All forms of VHF share similar symptoms including generalized flu-like symptoms in the early stages of infection with rapid progression into the defining symptoms. The general symptoms of VHF related disease include high fever, bleeding disorders, shock and in many cases results in death. Five families of RNA viruses are considered responsible for all VHF cases with the most recent identified in 2012. The viral families are Arenaviridae, Bunyaviridae, Filoviridae (Ebola), Flaviviridae and Rhabdoviridae.
|Viral hemorrhagic fever
||Generic terms for typically life threatening fevers including Ebola and Marburg
|Argentine hemorrhagic fever
||Caused by an arenavirus carried by corn mice
|Bolivian hemorrhagic fever
||Caused by the Machupo virus with mortality rates between 5 and 30%
|Brazilian hemorrhagic fever
||The Sabiá virus is responsible for the fever
|Crimean–Congo hemorrhagic fever
||Spread by a Tick-borne Virus
|Kyasanur forest disease
||Caused by Tick-borne virus from the same family as yellow fever
||Caused by the Lassa Virus
|Marburg virus disease
||The Marburg virus is a close relative of Ebola
|Omsk hemorrhagic fever
||Found in Siberia caused by a Flavivirus
|Venezuelan hemorrhagic fever
||Caused by the Guanarito virus
As you can see there are several known hemorrhagic fevers and although Ebola gets highlighted every few years during an outbreak it is certainly not the only virus to consider when a fever presents itself in a patient. Many of the diseases belonging to this category are endemic to certain areas around the world and all share the symptoms noted in late stage Ebola infections.
The Ebola Virus was first documented in 1976 when two outbreaks occurred in Sudan (now Sudan and South Sudan) and Zaire (now the Democratic Republic of Congo). The virus was named after the Ebola river in Zaire which runs nearby the Yambuku village which suffered the second ever outbreak of the virus. Ebola is a member of the Filoviridae family of viruses and is poorly documented and understood when compared to more common diseases.
Three common strains of Ebola were observed during earlier outbreaks namely Sudan, Zaire and Reston. The Reston strain is of particular interest being the only strain to exhibit fully airborne traits. Later, the Côte d’Ivoire strain was discovered when a ethologist infected herself while performing a necropsy on a chimpanzee in 1994. The 2014 Ebola outbreak was caused by the Zaire strain of Ebola. The virus is Zoonotic and usually found in animal reservoirs with human infections resulting from accidental infection in laboratories or the consumption of incorrectly prepared “bush meat”.
The first known Filovirus was Marburg which was discovered in 1967 during an outbreak in West Germany (now Germany). Marburg is similar to Ebola and outbreaks are rare. Uganda has a history of Marburg outbreaks which are typically contained rapidly through isolation and contact tracing. It is generally thought that Filoviridae have existed for thousands of years based on DNA evidence. Several ancient viruses share genetic material with modern examples of the virus family and some theories have been put forward suggesting that the “Plague of Athens” and the “Black Death” may have resulted from a Filovirus similar to Ebola.
Several conspiracy theories have suggested that Ebola may have been manufactured for use as a bio weapon. There is very little evidence to support such claims. After the discovery of Marburg and Ebola several documents have been declassified evidencing attempts to weaponize the virus however no success has been documented.
The plague is caused by a bacteria known as Yersinia pestis which is typically transmitted to humans by fleas. Y. pestis is responsible for several types of plague with at least one capable of aerosol transmission. The Plague is often referred to as the Bubonic Plague which has become synonymous for all common forms of plague.
By Photo Credit= Content Providers= CDC/ Courtesy of Larry Stauffer, Oregon State Public Health LaboratoryRsabbatini at en.wikipedia [Public domain], from Wikimedia Commons
The “Black Death” is frequently attributed to a form of plague most commonly Bubonic Plague. The Black death lasted from 1346 to 1353 and resulted in as many as 200 million deaths with nearly a third being attributed to Bubonic Plague according to some sources. Ebola made an appearance as a possible “Black Death” suspect in 2001 when it was suggested that the Black Death could have been caused by a Filovirus given that it spread far quicker than expected. The “Black Death” is also documented to have a significantly long incubation time which has been observed in both the Ebola and Marburg outbreaks. A large amount of the evidence which blamed the “Black Death” on the plague results from DNA confirmations that Yersinia pestis was present in samples of confirmed victim remains.
Table Comparing Ebola to the Plague
||Plague (Yersinia pestis)
||1.3 (Possibly Higher when Airborne)
||5 (CDC), 11 (WHO)
||25-90% / ~70% 2014 Outbreak
||11% with Treatment
||No, Possible Aerosol
||Bodily Fluids (Almost All)
||Flea Bites, Aerosol
||Yes, rarely used
||Humans, Primates, Bats
||Very Low Prior to 2014
||Less than 100 Confirmed
|Largest known Outbreak
||2013/14 West Africa
||Black Death (75-200 million deaths)
|| Active until 1959
||Thousands of Years
||Thousands of Years
The First Bio-Weapon
The plague is very likely the first known example of a biological weapon in warfare. In 1347 victims of the plague were catapulted into the city of Caffa (modern day Feodosia) leading to an outbreak. One theory is that the sufferers fled to Europe taking the plague with them. Japan used a similar approach against China during the second world war when contaminated rice and wheat dropped from an airplane resulted in a outbreak causing 121 deaths.
The idea that several diseases including the plague were caused by “bad air” is called the Miasma Theory. Upon the discovery of “germs” including bacteria and viruses the theory was replaced by the Germ theory of disease. It was thought that the vapor or fumes from decaying organic matter could cause disease. Plague Doctors were known for their beak like breathing apparatus which attempted to purify the poisonous air.
Plague is treated with antibiotics in the modern world and the prognosis is generally good if a patient seeks medical attention at the first sign of symptoms. Nostradamus famously treated plague sufferers with rose hips which provide a rich source of Vitamin C.
The plague is arguably one of the most infamous diseases and the “Black Death” is a well known pandemic across the world. Many modern medical practices are routed in the treatment of the plague including the concept of isolation and the purification of air via a respirator. The approaches taken during plague outbreaks were often ineffective but the concepts have found relevance in modern medicine.
In the heat of the media hype surrounding the Ebola outbreak it is possible that the Marburg outbreak in Uganda could be forgotten. Marburg is similar to Ebola although generally considered less lethal. On the 28th of September 2014 the first victim in Uganda died generating more than 100 contacts for surveillance. Updates from the region are spotty at best and often contradictory. The following update is based only on information with multiple sources.
- Five Ugandans are in isolation with no confirmations that Marburg has spread.
- Up to 149 contacts are being monitored for the virus.
- The nurse responsible for treating the first patient has tested negative to date.
- Kenya has placed health officials at key border points to monitor border crossings
- A possible second outbreak is being investigated and two patients have been isolated
- It is not clear how the index patients became infected. It is thought that previous outbreaks resulted from contact with Bat guano.
- On the weekend several tweets indicated that a second Marburg death had occurred. The Ministry has claimed the suspected patient died of “liver failure”.
- The World Health Organization has confirmed the outbreak and is monitoring the situation.
- Reports that at least 8 people developed symptoms have been denied by the official Health Ministry.
Uganda has extensive experience in dealing with Marburg. They recently brought an outbreak under control in 2012 as well as on several occasions before that. The virus displays similar symptoms to Ebola with the largest outbreak recorded in Angola during 2004 and 2005 where 252 cases were confirmed.
Ebola and Marburg outbreaks have occurred across the region in the past resulting in well established protocols and procedures for dealing with contagious diseases. If no new cases are reported by the 20th of October it is likely that the outbreak will be declared over by mid November 2014.
Marburg is a close relative of the Ebola virus with several similarities including a terrify fatality rate above 80%. State officials in Uganda announced yesterday a confirmed death related to the deadly virus in Kampala marking the first reported case since 2012 when the last outbreak occurred in the region.
The index case is a Health Care worker who developed symptoms last week. Samples sent for testing confirmed that Marburg was responsible. According to the Ugandan government at least 80 contacts have been identified and are being traced. The brother of the first case in 2014 has developed symptoms and has been placed in isolation while awaiting test results. No details are available surrounding the source of the transmission to the index case.
Marburg and Ebola are both Filoviridae and considered to be extremely lethal. The World Health Organization classifies any Filovirus as Bio-Safety Level 4. Marburg like Ebola typically causes viral hemorrhagic fever marked by the onset of headaches and fever before rapidly accelerating toward complete destruction of the host’s cellular system.
A key difference between Marburg and Ebola is the incubation time. Marburg has a typical incubation time of 2 weeks while Ebola has been documented to have an incubation time as long as 3 weeks. Marburg was first observed in 1967 when it infected 31 individuals across then West Germany and former Yugoslavia claiming 7 lives. The former Soviet Union famously experimented with Marburg (MARV) as a potential bio weapon.
The 2014 Ugandan outbreak is the 3rd active outbreak in 2014 attributed to a Filovirus, The Ebola outbreak in West Africa is not related to the outbreak in the Democratic Republic of Congo and therefore counts as separate epidemics. At present no cause or reason for the increased number of outbreaks is known and can be considered mere coincidence.