ELISA for Ebola Virus Disease (EVD)


ELISA for diagnosis of Ebola

The 2014 Ebola Outbreak is caused by Ebola virus (EBOV) and is currently ongoing in West Africa, including Guinea (the country of origin) and the east, the capital, Conakry, and the neighboring countries of Sierra Leone and Liberia. Four cases have occurred in Nigeria, in travelers from infected areas, and subsequently in health care workers. This outbreak is the most severe in recorded history in regards to both the number of human cases and fatalities. For research use, Ebola virus cDNA clones are now available.

What is Eblola Virus?

Ebola virus (Zaire ebolavirus or EBOV or ZEBOV) belongs to genus Ebolavirus which has other four species including Sudan eoblavirus (Sudan ebolavirus, abbreviation:SUDV); Taï Forest ebolavirus (Taï Forest ebolavirus, formerly Côte d'Ivoire ebolavirus, abbreviation:TAFV,) and Bundibugyo ebolavirus (Bundibugyo ebolavirus, abbreviation:BDBV). The Ebola virus (Zaire ebolavirus or EBOV) is the most dangerous of the five Ebolavirus species which are the causative agents of Ebola virus disease. And Ebola virus (EBOV) is the type species of Ebolavirus. The virus causes an extremely severe hemorrhagic fever in humans and other primates. Ebola virus (EBOV) is a select agent, World Health Organization Risk Group 4 Pathogen.

The Ebola virus (EBOV) contains a linear, single-stranded, negative-sense RNA genome which is approximately 19 kb in length. It encodes seven structural proteins and a non-structural protein. Structural proteins are nucleoprotein (NP), polymerase cofactor (VP35), (VP40), GP, transcription activator (VP30), VP24, and RNA polymerase (L). The characteristic of Ebola virus genome is that the 3'terminus is not polyadenylated and the 5'end is not capped.

The EBOV virion is filamentous, pleomorphic with extensive branching or U-shaped or 6-shaped with a diameter around 80 nm and a variable length up to 1400 nm. It is enveloped by lipid bilayer, with anchored glycoprotein GP forming the viral spikes on the surface. It contain a single linear RNA molecule, nucleoprotein (NP), nucleocapsid viral protein 30 (VP30), VP35, and polymerase (L) in the core. Matrix proteins VP24 and VP40 are present in the space between the core and envelope.

Eblola Virus Disease (EVD) Symptoms

Ebola virus symptoms may appear anywhere from 2 to 21 days after exposure to ebolavirus though 8-10 days is most common. Ebola virus symptoms If infected by Ebola virus, people will have a sudden onset of fever after incubation period. If untreated, the fatality rate can reach 90%. Even be treated, people have to accept the fact that the fatality rate is as high as 60%. Typical Ebola virus symptoms are similar to flu or dengue fever, including fever, headache, joint and muscle aches, weakness, diarrhea, vomiting, stomach pain and lack of appetite. This is followed by vomiting, diarrhoea, rash, impaired kidney and liver function. Some patients may also experience red eyes, hiccups, cough, sore throat, chest pain, difficulty breathing and difficulty swallowing. And finally, it turns into both internal and external bleeding.

Bleeding is the worst Ebola virus symptom. It involves internal and external bleeding, such as skin bleeding and visceral hemorrhage. Internal bleeding results to red eye and bloody vomit, coughing blood up or blood in the stool. Bleeding into the skin may cause petechiae, hematomas and so on. In general, the development of bleeding symptoms often indicates a worse prognosis and this blood loss can result in death.

Eblola Virus Disease (EVD) Symptoms

Diagnosis of Eblola Virus Disease (EVD)

Ebola virus disease (EVD) or Ebola hemorrhagic fever (EHF) is the human disease caused by the Ebola virus. Symptoms typically start two days to three weeks after contracting the virus, with a fever, sore throat, muscle pains, and headaches. Typically nausea, vomiting, and diarrhea follow, along with decreased functioning of the liver and kidneys. At this point, some people begin to have bleeding problems.

If having some Ebola virus symptoms of Ebola virus disease, the patient should be isolated first. Samples should be sent to a laboratory to confirm infection. Because samples from patients are a source of infection risk for others, testing is conducted under maximum biological containment conditions. Within a few days after EVD symptoms begin, an antigen-capture enzyme-linked immunosorbent assay (Sandwich ELISA) is necessary for EVD diagnosis.

Diagnosis of Eblola Virus Disease (EVD)