Ebola virus is a virus of the filoviridae (filovirus) family that causes fever severe, called Ebola virus disease or VHF for viral hemorrhagic fever. Particularly virulent, the Ebola virus can cause death (between 25 and 90% of mortality depending on the epidemics). The 2014 epidemic has, according to the WHO, a mortality rate of around 54%.

Ebola haemorrhagic fever is a very serious, contagious disease, potentially deadly. WHO calls it “one of the most virulent diseases in the world”.

There is no treatment that can cure Ebola fever, nor approved vaccine to prevent this Ebola hemorrhagic fever. The aim of the care provided is to combat the symptoms caused by the disease and to help the patient survive the infection. There are a few healing case following the administration of unauthorized treatment, which raises a lot of hope. Researchers are also working on the development of a virus to fight this serious disease.

The Ebola virus can strike all year round and can affect anyone, men or women, young or old. Experts don’t know why some people survive and others don’t. People who are cured can pass the virus on for up to 7 weeks after recovery. People who die can also transmit the disease.

The reservoirs of the Ebola virus are bats. They can transmit this virus to other animals, such as monkeys. Humans can be contaminated via these animals (contact with their blood, by eating their meat, etc.). Then, transmission during epidemics occurs between humans.

The foci of epidemics are located in Africa. The Ebola virus was discovered in 1976¹ by the river of the same name, in the former Zaire (now Democratic Republic of Congo). There are five forms: Bundibugyo, Ivory Coast, Reston, Sudan and Zaire. The latter is the form that struck Africa in 2014. The first epidemic of 1976 killed 431 people. Then the epidemics followed one another. That of 2014, which appears to be the most serious epidemic, started in February and has already killed more than 2000 people 7 months later.

Prevalence

In each epidemic, the Ebola virus affects a different number of people, and the percentage of deaths among infected people varies according to the epidemic. According to the WHO, the 2014 epidemic would see a death rate of 54 % about.

Diagnostic

Viral hemorrhagic fever caused by the Ebola virus is difficult to diagnose. First, because the first symptoms can be similar to other diseases such as malaria, or malaria, or cholera, or food poisoning. Secondly, because it is almost impossible to carry out blood tests in the regions concerned, because there is no high security laboratory in the field. The presence of the Ebola virus is indeed confirmed following various blood tests like the Elisa test.

It is therefore very important to know whether the person has been in contact with a person infected with the Ebola virus in the previous three weeks or whether they attended a funeral by touching the deceased person in the previous three weeks.

Japanese researchers have recently reportedly developed a faster and cheaper screening test: a process that would give a result in half an hour, but which is not yet available.

Complications

The Ebola virus causes fevers. The disease can progress to jaundice, delusions, convulsions, severe hemorrhage, coma.

People who recover from Ebola virus disease carry the virus for weeks after their infection and can therefore, although cured, infect their loved ones. In addition, infected people are all the more contagious as their disease worsens.

Causes

The Ebola virus is believed to have some bats as a natural host. This virus can be transmitted to animal species such as monkeys and chimpanzees. The latter can be transmitted to humans through bodily fluids, for example during the slaughter of an animal. Then the virus is transmitted from person to person by direct contact (through saliva, blood, urine, stool, semen, vomit, or contaminated clothing) or contaminated needles during medical treatment. Transmissions do not occur through the airways.

Infected people are not contagious than the appearance of the first symptoms – there is indeed an incubation period (period between the arrival of the virus in the body and the first signs of the disease) of several days (between 2 and 21).

After healing, a person can still be contagious for 7 weeks.

Infected people are still contagious after they die. Infections during funeral rites are also frequent.

Medical personnel may also be infected if they do not use suitable protective equipment: gloves, gowns, boots, masks, glasses.