Ebola virus & its disease

Ebola virus is one, which causes fatal hemorrhagic diseases in human and other mammals (like gorilla, chimpanzee, and monkeys etc), that previously known as Ebola hemorrhagic diseases. It belongs to negative (-ve) sense, single stranded RNA enveloped virus, further classification is  Mononegavirales (order), Filoviridae (family), Ebola (genus). Ebola virus and its genus were both originally named for Zaire, the country where it was first described, and was at first suspected to be a new "strain" of the closely related Marburg virus, The virus was renamed "Ebola virus" in 2010.  There are five identified Ebola virus species, four of which are known to cause disease in humans: Ebola virus (Zaire ebolavirus); Sudan virus (Sudan ebolavirus); Taï Forest virus (Taï Forest ebolavirus, formerly Côte d’Ivoire ebolavirus); and Bundibugyo virus (Bundibugyo ebolavirus). The fifth, Reston virus (Reston ebolavirus), has caused disease in nonhuman primates, but not in humans. The natural reservoir of Ebola virus is believed to be bats, particularly fruit bats, and it is primarily transmitted between humans and from animals to humans through body fluids

Brief General History of Ebola

In 1976, Ebola (named after the Ebola River in Zaire) first emerged in Sudan and Zaire. The first outbreak of Ebola (Ebola-Sudan) infected over 284 people, with a mortality rate of 53%. A few months later, the second Ebola virus emerged from Yambuku, Zaire, Ebola-Zaire (EBOZ). EBOZ, with the highest mortality rate of any of the Ebola viruses (88%), infected 318 people. Despite the tremendous effort of experienced and dedicated researchers, Ebola's natural reservoir was never identified. The third strain of Ebola, Ebola Reston (EBOR), was first identified in 1989 when infected monkeys were imported into Reston, Virginia, from Mindanao in the Philippines. Fortunately, the few people who were infected with EBOR (seroconverted) never developed Ebola hemorrhagic fever (EHF). The last known strain of Ebola, Ebola Cote d'Ivoire (EBO-CI) was discovered in 1994 when a female ethologist performing a necropsy on a dead chimpanzee from the Tai Forest, Cote d'Ivoire, accidentally infected herself during the necropsy. 

Causes of Ebola disease & their transmission

From animal to animal

The Ebola virus likely originated in African fruit bats. The virus is known as a “zoonotic” virus because it’s transmitted to humans from animals. Humans can also transfer the virus to each other. Other animals known to transmit the virus include:

·         chimpanzees

·         forest antelopes

·         gorillas

·         monkeys

·         porcupines

From person to person

Since people may handle these infected animals, the virus can be transmitted via the animal’s blood and body fluids. Once people become infected with Ebola, they can transmit it to others if people come in contact with their:

·         breast milk

·         feces

·         saliva

·         semen

·         sweat

·         urine

·         vomit

These bodily fluids can all carry Ebola virus. People can get Ebola when they come in contact with these fluids via the eyes, nose, mouth, or broken skin & people, who are involved in sexual activities. Healthcare workers are especially at risk for experiencing Ebola because they often deal with blood and bodily fluids.

Ebola can also be spread through sticks from infected objects, such as needles, and interactions with infected animals. Insects like mosquitoes are not linked with carrying Ebola.

Symptoms

Signs and symptoms typically begin abruptly within five to 10 days of infection with Ebola or Marburg virus. Early signs and symptoms include:

·         Fever

·         Severe headache

·         Joint and muscle aches

·         Chills

·         Weakness

Over time, symptoms become increasingly severe and may include:

·         Nausea and vomiting

·         Diarrhea (may be bloody)

·         Red eyes

·         Raised rash

·         Chest pain and cough

·         Stomach pain

·         Severe weight loss

·         Bleeding, usually from the eyes, and bruising (people near death may bleed from other orifices, such as ears, nose and rectum)

·         Internal bleeding

Incubation period 

Patients with Ebola virus disease typically have an abrupt onset of symptoms 6 to 12 days after exposure (range 2 to 21 days). There is no evidence that asymptomatic persons still in the incubation period are infectious to others. All symptomatic individuals should be assumed to have virus in the blood and other body fluids, and appropriate safety precautions should be taken

Diagnosis

Ebola virus is detected in blood only after onset of symptoms, most notably fever, which accompany the rise in circulating virus within the patient's body. It may take up to three days after symptoms start for the virus to reach detectable levels. Laboratory tests used in diagnosis include:

·         Enzyme-linked immunosorbent assay (ELISA)

·         Reverse transcriptase polymerase chain reaction (RT-PCR)

·         IgM and IgG antibodies presence in blood.

·         Immunochemistry testing.

Laboratory findings — Patients with Ebola virus disease typically develop leukopenia, thrombocytopenia, and serum transaminase elevations, as well as renal and coagulation abnormalities. Other laboratory findings include a marked decrease in total plasma protein and elevated amylase levels.

Treatment

Currently, no specific therapy is available that has demonstrated efficacy in the treatment of Ebola hemorrhagic fever. Surgical intervention generally follows a mistaken diagnosis in which Ebola-associated abdominal signs are mistaken for a surgical abdominal emergency. Such a mistake may be fatal for the patient and for any surgical team members who become contaminated with the patient’s blood.

There are no commercially available Ebola vaccines. However, a recombinant human monoclonal antibody directed against the envelope GP of Ebola has been demonstrated to possess neutralizing activity. This Ebola neutralizing antibody may be useful in vaccine development or as a passive prophylactic agent. Work on a vaccine continues.

FAQ:

1.    Do you ever see a patient, who suffers from Ebola viral disease?

2.    What symptoms do you observed in him?

3.    Had you find something wrong in above information? If yes; then give me your feedback..