Medical Health Information

Up to date, the ebola virus was a half-dozen sources violent outbreaks especially in West Africa. - The Ebola virus was first identified in 1976 in Sudan as well as Nzara Yambuku northern Zaire. June November 1976, the Ebola virus infected 284 people in Sudan by 117 deaths. In Zaire, there were 318 cases with 280 deaths in October from September. An isolated case occurred Tandala in Zaire in 1977 and a second blaze broke out in Sudan in 1979.

- In 1989 and 1990, a filovirus named Ebola-Reston was isolated from macaque monkeys quarantined laboratories in Reston (Virginia), Alice (Texas) and Philadelphia (Pennsylvania) in the USA.
These monkeys all came quarantine export licenses dune near Manila in the Philippines where the virus was also isolated.

- A large epidemic occurred in Kikwit in Zaire in 1995, there were 315 infections including 244 deaths.

- An isolated case of Ebola hemorrhagic fever and epidemic among chimpanzees were also observed in Ivory Coast in 1994.

- In Gabon, the first outbreak of Ebola haemorrhagic fever virus was identified in 1994, other outbreaks were documented in February 1996 and July 1996.

- No infection with Ebola virus navait been reported until this epidemic quéclate Gulu in Uganda in the fall 2000.

In total, approximately 1,100 cases with 800 deaths have been identified since the discovery of the virus.
virology

The haemorrhagic fever viruses are divided into four families: The flaviridés the bunyaridés the Arenaviridae and Filoviridae which are the longest virus that we know.

Ebola belongs to the family of filoviridae, gender filoviruses which includes several different biotypes: the débola Zaire virus (called Mayinga), Ebola Sudan and Ebola Reston.

Ebola virus is an enveloped single-stranded RNA viruses (helical nucleocapsid) which is similar to the morphology of Marburg virus antigenic structure but differs.
It can measure up to 1500 nm long with a diameter of 80 nm.

Natural Reservoir

Primary human cases result from contamination from an animal reservoir and then the very high contagiousness of the disease is responsible for a large diffusion.
The natural reservoir of the Ebola virus seems to inhabit rainforests and dAfrique Dasie, but it has not yet been identified.

Related to Ebola filoviruses were isolated from cynomolgus monkeys (Macacca fascicularis) that had been imported from the Philippines to the United States of America in 1989. But the virus kills primates too quickly for them is a good tank .

Recent work by a team of CNRS Rennes in collaboration with the Institut Pasteur in Bangui, have uncovered sequences of the virus in different organs of 242 small mammals.

Transmission

After the accidental contamination of a first man, the virus is then transmitted from the body fluids of a patient in clinical phase through direct contact with blood, secretions, organs or semen infected (saliva, blood, urine, faeces of patients are rich in virus) or by contact with the aerosol, and vomit may be sweat. The ingestion of infectious materials is associated with a risk of infection and a high fatality rate. Potential transmission through sexual contact with a patient cured is not determined, but it was shown that the Ebola virus is found in the genital secretions of convalescents several weeks after illness. Contamination therefore has a strong family or nosocomial. - Family Transmission: In families, the two major risks patient care and funeral toilet. - Transmission caregivers: During epidemics, lack of hygiene, lack of sterilization of equipment and especially needles and syringes contaminated facilitated nosocomial transmission of the virus.

Airborne transmission has been particularly studied in the survey conducted in the families of 34 cases of Nzara in 1979. This survey showed no risk due to a simple cohabitation in the same room and a five times higher risk for people with physical contact due to patient care compared to those with only "family" contacts.

Clinical signs

Incubation time: 2 to 21 days - 5 to 12 days in most cases.
Duration of illness: from 6 to 10 days in fatal forms.

Ebola hemorrhagic fever occurs in most patients within a few days after infection by a sudden rise in temperature, with fatigue, muscle pain, headache, and diarrhea.
Some patients may show sore throat, hiccups, rash, vomiting blood and bloody diarrhea (called "red diarrhea" in Francophone Africa). Other symptoms may occur: conjunctivitis injected dysphagia.

The patient is extremely asthenic quickly and has a significant weight loss, due to both the lack of nutrition of this weakness in the absence of food and the disease itself.

Followed by vomiting, diarrhea, maculopapular rash, kidney and liver damage and bleeding diathesis; liver damage, pancreatic, kidney, and to a much lesser extent, of the CNS and of the heart; leukopenia, thrombocytopenia and elevated transaminases.

Fever, often undulating in the early days, may disappear in the terminal phase.

Death is preceded by the appearance of tachypnea, hypotension, tachycardia, and anuria. The limited data available do not show pulmonary explaining tachypnea, and blood loss due to hemorrhage is still too low to explain the hypotension.

Diagnosis

The diagnosis is difficult because précoses symptoms such as red eyes and itchy eyes are nonspecific. If someone shows symptoms mentioned above and the Ebola virus infection is suspected, several laboratory tests are to be made (ELISA, virus isolation).

"Lhospitalisation of isolation with appropriate measures, including during transport, SimPose to viral haemorrhagic fever clinical suspicion: recent fever quickly create an accompanying rash (4-5 th day) and hemorrhagic signs superficial and visceral (6-7 th day) an epidemic quickly taking shape step by step in the population. "(therapeutic protocol support for victims, record No. 6" Agents of viral haemorrhagic fevers ").

The fatality rate is between 50 and 90%. Most often, death is caused by a cerebral embolism (stroke).

Processing

There is no specific treatment or vaccine. There is no serotherapy.

Severe cases are placed in the intensive care unit: these patients are dehydrated and need to be placed on a drip for rehydration.

Maintain kidney function Treatment aims and electrolyte balance and combat hemorrhage and shock. Replacement of coagulation factors and platelets can be useful.

For patients who survive, recovery is accompanied by intense fatigue and arthralgia migrants often affecting large joints.

Prevention and safety

Suspected cases should be isolated from other patients and caregivers should operate under conditions of high security. Hospital staff should wear gowns, gloves and masks individual. Gloves and masks should not be reused unless they have been disinfected. Very important for certain actions such as the installation of an infusion risk, handling of blood and secretions, catheters and suction devices, which must be carried out in conditions of high security. The dead must be buried or cremated quickly.

Conclusion

Viruses such as Ebola existed for millions of years, long before the appearance of man. They can not live in free society and they rarely come out of their tank because they do not have the ability to easily colonize new host species.

Meet other species is an accident that does not result in the long term sustainability of the virus into a new species.

Low risk to the human population except where the possibility of coexisting primary contamination, poor hygiene and social structures disrupted.

FOCUS - With its unprecedented scale and because of the dispersion of foci of infection, epidemic hemorrhagic fever worries the international community.

When the virus appear?

The discovery of the virus dates back to 1976, when the first recorded outbreak in Zaire, now the Democratic Republic of Congo in a near Ebola, the disease got its name River area. He then hit 318 people and killed 280. Its origin is debated to this day. A widely accepted hypothesis, some species of bats living in the tropical forests of Central Africa and West Africa, are the natural hosts of Ebola. Other animals also participate in the transmission cycle. Five viral species have been identified since then, but both are responsible for the vast majority of contamination: the Zaire strain - one mutation now raging - and the Sudan strain.

Which countries are involved?

Ebola comes sporadically and at irregular intervals. The latest resurgence starting date of the year. The outbreak was first reported in Forest Guinea before spreading in Liberia, Sierra Leone and Nigeria. Until recently, the virus raged mainly in central and eastern Africa. From 1976 to 2012, in addition to the Democratic Republic of Congo and Sudan, three other countries had been affected by serious epidemics: Gabon, Uganda and Congo. Together, they have killed more than 2,200 people in forty years, much less than the AIDS virus or malaria. The fatality rate is itself much higher: it varies from 25% to 90%, depending on the strain. According to WHO, it currently stands at 54%.

What are the symptoms?

Symptoms of infection with Ebola are impressive: internal and external bleeding, mucosal bleeding, vomiting and diarrhea, often accompanied by blood. Poorly perfused, organs eventually become necrotic, and the skin soften and tear. The current epidemic in West Africa nevertheless induces slightly different symptoms. "Vomiting and diarrhea are predominant in this epidemic, says Herve Raoul, director of the Inserm-P4 laboratory in Lyon. Observed less profuse bleeding, and it would be more correct to speak this time of infection with Ebola virus, not hemorrhagic fever. "

How is the virus spread?

Transmission between humans is the main driver of the epidemic. "Transmission occurs through contact with body fluids of an infected person, adds Herve Raoul. Just as blood, secretions or feces come into contact with mucous membranes or wounds so that the infection spreads to a new host. "The contamination is thus most often among relatives or caregivers. But the people who died are contagious and a physical contact with a corpse is dangerous. Funeral rites and play a very important role in the transmission of the disease.

How the epidemic is it treated?

Currently, no treatment exists. In hospitals and treatment camps, caregivers simply help the body fight infection. "We unfortunately can not do much to treat disease and the symptoms, says Geraldine Bégué. We often simply hydrate patients intravenously and isolate them from the rest of the population to avoid contagion. "Molecules and vaccines have already yielded some results on animals, but no results on humans n 'is still available. A serum called ZMapp, the American firm Mapp Biopharmaceutical, administered experimentally in two American patients. And the United States has partially lifted restrictions on another experimental treatment Tekmir of Canadian society, but placing it on the market could take several months.

Why this new epidemic she worried?

The actors of this health crisis are likely to worry about the latter resurgence of the virus. WHO estimates Ebola should continue to spread for several months. However, it is already the worst epidemic in the history of this disease since its discovery and the number of victims grows exponentially. Especially as its dispersion and multiplication of homes make it difficult to curb the phenomenon. Many experts also worry that for the first time the disease thrive in urban areas. The work of health personnel is also complicated by the suspicion of the local population vis-à-vis Western caregivers.