Ebola Virus - Transmission, Symptoms and Treatment

Haemorrhagic fever Ebola, better known as Ebola, is a severe viral disease discovered in the 1970s in central Africa. The Ebola mortality rate is as high as 90% depending on the virulence of the strain, the immune system of the patient and the health conditions of the sites affected by outbreaks.


Ebola is currently restricted infection to remote regions of the continent, however, with episodes of outbreaks in urban areas in countries such as Uganda, Nigeria, Democratic Republic of Congo (formerly Zaire), Sadao, Guinea, Liberia, Sierra Leone and others. Being a highly lethal disease and the possibility of transmission between humans, every time an Ebola outbreak affects major cities of Africa, health authorities around the mute are on alert because of the possibility of the virus being brought accidentally by some traveler.

In this article we will explain what is Ebola, what its causes are, transmission, symptoms and how it should be done the treatment and isolation of the infected patient. We'll talk also about the risk of an outbreak of Ebola arriving in Brazil.


Ebola is one of the existing forms of viral hemorrhagic disease. In Brazil, we have dengue and yellow fever, which are also viruses that can cause hemorrhagic complications. Ebola, however, is a completely different virus family dengue and yellow fever, and being more virulent form of separate transmission.

The virus Ebola was first identified in 1976, after simultaneous outbreaks in Sudan and the Democratic Republic of Congo, the latter in a region located near the river Ebola, which ended up giving name to the disease. Since then, several Ebola outbreaks have occurred throughout central Africa and recently in the western region. Between 2000 and 2014 have been described more than 10 Ebola outbreaks in Africa.

The Ebola disease is caused by a virus of the family Filoviridae having 5 different species, which are named according to location that have been identified:

• Ebolavirus Ivory Coast.
• Ebolavirus Sudan.
• Ebolavirus Zaire.
• Ebolavirus Bundibugyo.
• Ebolavirus Reston.

Of the five species of Ebolavirus already known, only Reston does not seem to be capable of causing disease in humans, restricting the monkeys.


There are three ways of contracting Ebolavirus: human transmission to human contamination through contact with infected animals and laboratory accidents with infected biological material. Let's talk briefly about these three routes.

a) Transmission between humans

Contrary to what a lot of people think, the Ebolavirus is not a highly contagious virus is usually not transmitted through the air through respiratory secretions, such as flu or cold. Transmission between humans occurs by contact with blood or infected secretions such as urine, feces or vomit.

Transmission can also occur through indirect means, through contact with objects that may have been contaminated with these secretions. The Ebola virus is able to survive in the environment for several days, either in wet or dry locations. Therefore, to avoid contamination of other people, places that may have housed a sick patient should be isolated and decontaminated. Ebola is a virus may be inactivated with common disinfectants, such as alcohol, bleach or soaps based on sodium lauryl sulfate. So in times of outbreaks, wash your hands often is an important measure of protection. As excessive heat also kills the virus, suspicious objects boil for a few minutes is a way to sterilize suspicious objects.

Unlike dengue and yellow fever, Ebola virus is not transmitted by mosquitoes. In fact, if Ebola was as contagious as the flu or if it could be transmitted by mosquitoes, the disease would have spread throughout the African continent, and probably other parts of the world.

The main risk for the transmission of Ebola are the families of patients who take care of them in the early days of symptoms. Contact with vomiting, diarrhea or blood are the most common forms of contamination of relatives. The lack of adequate sanitation in many places of the African continent facilitates the spread of the virus.

Fortunately, patients with Ebola only becomes infectious when the symptoms arise, which makes it easy isolation thereof and the contact prevention next to families. When there are outbreaks, people should be advised to look for a hospital as soon as the first symptoms appear. Staying home sick increases the risk of contamination of people living under the same roof.

Another very important way is the transmission within hospitals. The transmission to the health staff or other patients can be prevented if safety measures are taken, such as patient isolation, proper treatment of contaminated materials and the use of special clothing such as gowns, masks and gloves. This, unfortunately, does not occur in many hospitals and care units of Central Africa countries. In the most poverty-stricken areas are frequent handling of reports of ill people without gloves and masks, plus the relocation campaign units where patients are separated only by makeshift tents.

The spread of the virus is slow, but the lack of information and health conditions favor the occurrence of outbreaks. The 2014 outbreak, for example, appears to have been triggered at the end of 2013. A mixture of lack of access to health centers, lack of awareness campaigns, inability to put patients in quarantine and the presence of guerrillas in the affected sites, end making a not very contagious virus can spread to large areas of the African continent.

When appropriate security and isolation measures are taken, the risk of in-hospital infection or outbreak in the population becomes low. Just as an example, in 1998, a patient with Ebola was admitted in South Africa for investigation and treatment of a hemorrhagic fever frame initially unknown cause. As proper precautions are taken, of the 300 professionals who have had direct or indirect contact with the patient, only one was infected. Among the other hospital patients, none were contaminated. There was no outbreak and the disease is not established in that country.

It is for this reason that countries like the US and Spain have accepted the repatriation of citizens who were infected in African countries. The risk of an outbreak is triggered by these patients is very low, since the preventive measures are followed.

b) Transmission through animals

Outbreaks among humans usually start through contamination of a person by an infected animal. It is believed that the fruit bats are the major virus reservoir. There are several reported cases of contamination of people who attended environments full of bats, such as mines, caves or forests.

Non-human primates are also a common source of infection. It is believed that macocos be contaminated by ingesting debris discarded as contaminated fruit bats. The transmission monkey to humans has been described, especially where the consumption of meat of this primate is common. In 1996, Gabon, one of the Ebola outbreak was triggered after 19 people have consumed chimpanzee meat.

c) Accidental contamination with infected biological material

Over the past 40 years, several cases of contamination by professionals who deal with the Ebola virus laboratory level have been reported. The cases have occurred not only in the African countries themselves where an outbreak was underway, but also in laboratories outside the risk areas, such as USA and Russia.


The Ebola incubation period is generally 5 to 7 days, but cases more than 20 days are reported form. Unlike many common viruses, patients in the incubation period are not able to transmit the virus. The contagious period begins only when the first symptoms appear.

Ebola infection frame usually begins abruptly with high fever, chills, malaise, prostration and muscle pain. Vomiting, diarrhea, sore throat and headaches are also very common. Initially, the frame can be much like any stronger virus, like the flu, for example.

The disease remains more or less stable in the early days, but starts to worsen at the end of the first week. Reduced level of consciousness, hypotension, kidney and liver failure, skin rashes and bleeding, especially in the eyes are signs of severity.

In general, patients entering the second week did not begin to show signs of improvement are those most likely to die. Laboratory tests, such recovery in the second week is related to a decrease in the levels of circulating virus in the blood and an increase in the number of specific antibodies against Ebola virus. The factor that seems to define the patient's prognosis is the ability of your immune system to react quickly and mount an immune response against the virus. The patients who die are those who until the second week has not managed to control the virus replication or produce adequate levels of antibodies.


Although there is no specific treatment for Ebola. As in the cases of dengue fever, Ebola treatment is supportive. The medical team's goal is to provide conditions for the patient to stay alive while your immune system fight the invading virus. mechanical ventilation, dialysis, drugs to control blood pressure, blood transfusions and other measures may be needed to keep the patient alive in the most critical stage of the disease.

Again, as in the case of dengue, there is still no vaccine against Ebola virus.

Since there is no treatment or vaccine available, the control of Ebola outbreaks depend on hygiene conditions, quality of hospital centers, the ability to create quarantines and the population awareness on ways of contagion in the areas at risk of outbreak.