Why does Ebola cause bleeding in some people?

Why does Ebola cause bleeding? Scientists are still trying to understand how the virus works, and this article will explore some of the latest findings.

Why does Ebola cause bleeding in some people?
An Ebola survivor donating blood plasma.

Ebola is a deadly virus that causes very visible and serious bleeding in some people, typically around the eyes, nose, and mouth. But why does Ebola cause bleeding? Scientists are still trying to understand how the virus works, and this article will explore some of the latest findings.

Ebola was first discovered in 1976 near the Ebola River in Sudan. There is some interesting research and speculation that Ebola might have been present in humans long before 1976, but there is no conclusive evidence that has decisively proven this. Because the pathogens responsible for the virus are primarily found in Africa, outbreaks are most likely to originate there.

From 2014 through 2022, 32,311 people have contracted Ebola, of which 13,708 have died - a staggering 43% overall case fatality rate.

What are the signs and symptoms of Ebola virus disease?

The average EVD case fatality rate is around 50%. Case fatality rates have varied from 25% to 90% in past outbreaks. Early symptoms of EVD include fever, fatigue, muscle pain, headache, and sore throat. These are followed by vomiting, diarrhea, rash, impaired kidney and liver function, and in some cases, both internal and external bleeding.

People are infectious as long as their blood and secretions contain the virus. EVD is diagnosed through laboratory testing of blood or body fluids. There is no specific treatment for EVD, but patients can receive supportive care to treat symptoms. There is currently no licensed vaccine available for EVD.

The Ebola virus is thought to be maintained in fruit bats, and humans can become infected through contact with the bats or with infected nonhuman primates. The disease then passes from person to person through direct contact with infected bodily fluids. Appropriate infection-control measures are essential for controlling the virus.

What animal started Ebola?
The natural host of the Ebola virus is unknown. What might be the animal that started Ebola?

How common is bleeding in patients with Ebola?

The Ebola virus disease (EVD) was previously referred to as Ebola hemorrhagic fever, but it is now known that not all patients with EVD experience hemorrhagic manifestations. However, Ebola is probably most known for the unexplained hemorrhage (bleeding or bruising) that often comes with it. In the 1976 outbreak that led to the discovery of the Ebola pathogen, 75% of patients bled from various parts of their body. Since contact with infected blood is a common way to acquire infection, this made the job of treating sick patients especially difficult and dangerous.

However, in more recent outbreaks, hemorrhagic manifestations have been reported less often. For example, in the 1995 outbreak of the Ebola virus in Kikwit, the Democratic Republic of Congo, 41% of the patients had hemorrhagic manifestations.

In the 2001 outbreak of the Sudan strain of the virus in Uganda, 30% of the patients had hemorrhagic manifestations. A total of 46.5% of people affected by the Bundibugyo virus in Uganda in 2007 had hemorrhaged.  In Sierra Leone, the New England Journal of Medicine in 2014 noted that bleeding occurred in just 1 of 87 Ebola patients. So, bleeding is not a consistent symptom.

This inconsistency makes identifying Ebola tricky. Laboratory findings in Ebola patients include low white blood cell and platelet counts and elevated liver enzymes. It can be difficult to clinically distinguish EVD from other infectious diseases such as malaria, typhoid fever, and meningitis.

How does bleeding appear in patients with Ebola?

Most people who do have bleeding from Ebola bleed from their eyes, gums, nose, and mouth. They may also bleed in their gastrointestinal tract and ooze blood from puncture sites.

This bleeding has led some people to ask if Ebola can turn you into a Zombie after you die. A disease that causes patients to ooze blood from their eyes, mouth, and other body parts creates a conspicuous set of symptoms that can lead to widespread public fear. With fear comes rumors, and one such rumor that took root on the internet was that Ebola could turn you into a "zombie" after you died.

Here are a couple of examples of headlines that contributed to this fear:

Why do some people bleed when they have Ebola?

There is a lot we still don't know about what causes the bleeding in Ebola virus disease. One theory has been that the cause is disseminated intravascular coagulopathy (DIC), but this has not been proven. There is a published report of one patient who had DIC, but this patient was in a tertiary care center and most patients with Ebola virus disease are in rural Africa where these measurements are not routinely taken. Several case reports have demonstrated that platelets are low in patients who have Ebola virus disease, but prothrombin time, fibrinogen; and fibrin split product measurements are not routinely performed.

Diarrhea associated with Ebola virus disease tends to be profuse, watery, and non-bloody. In some cases, bloody diarrhea has been reported, but it is not clear if this is due to an inflammatory process or actual hemorrhage. Additional studies are needed to determine the cause of bloody diarrhea in patients with Ebola virus disease.

A study using blood samples from the Gulu outbreak in Uganda did not show any association between DIC and bleeding. These data suggest that DIC probably is not the real cause of the bleeding in Ebola virus disease.

How do they treat patients who are bleeding from Ebola?

There is no definitive treatment for DIC, as its causes are not fully understood. The British Committee for Standards in Haematology offers guidelines on managing DIC in intensive care settings, but there is no evidence that these treatments improve survival rates. In fact, treating coagulopathy could potentially make bleeding worse. Further research is needed to determine the best course of action for managing this condition.

There is no laboratory test that can predict whether patients are going to develop bleeding with the possible exception of platelet count, which is not being done in the field.

In addition to treating bleeding, the CDC outlines other measures that form a supportive care regime:

"Whether or not other treatments are available, basic interventions can significantly improve chances of survival when provided early. These are referred to as supportive care and include:

  • Providing fluids and electrolytes (body salts) orally or through infusion into the vein (intravenously).
  • Using medication to support blood pressure, reduce vomiting and diarrhea, and to manage fever and pain.
  • Treating other infections, if they occur."

Lastly, two treatments have been approved by the FDA to treat EVD caused by Ebola virus, Inmazeb and Ebanga. These treatments were found to be effective in a randomized controlled trial during the 2018-2020 outbreak in the Democratic Republic of the Congo. They are monoclonal antibodies that bind to the Ebola virus and prevent it from entering cells. This helps with treatment because it stops the virus from replicating.

If you bleed from Ebola, does that mean you are going to die?

In a study of the Sudan strain of the Ebola virus that was published in 2014, there was no statistically significant link between bleeding and case fatality rate. There was also no association between bleeding and death rate in two other studies - one conducted in 1995 and the other in 2007.

Can blood transfusions from a healthy person save you if you are ill with Ebola?

There is conflicting evidence as to whether or not convalescent plasma transfusions—which involve taking blood from survivors of an Ebola outbreak and transfusing it into patients who are actively infected—are effective.

What is convalescent plasma? It is a blood product that is collected from individuals who have recovered from an infection with a pathogen, such as the novel coronavirus. The plasma contains antibodies that can help protect other people who are exposed to the same pathogen. These products can be helpful because they provide immunity without the need for vaccinations.

One study, which was conducted during the Kikwit outbreak in the 1990s, found that seven out of eight patients who received convalescent plasma survived. However, this study was small and did not have a control group. Additionally, all seven of the survivors had received their transfusion during the second week of their illness—at which point mortality rates are known to be lower.

More recent studies on nonhuman primates have found that antibodies can be effective in preventing Ebola both before and after exposure; however, it is unclear if this would translate to humans. Therefore, more research is needed before any conclusions can be drawn about the efficacy of convalescent plasma therapy for treating Ebola.

If you're interested in following news about these efforts or want to stay up to date on other Ebola facts and news, be sure to follow us on Twitter at the link below - and be sure to share this article with others who want to stay in the know.