EBOV proteins blunt the human immune systems response to viral infections by interfering with the cells ability to produce and respond to interferon proteins such as interferon-alpha, interferon-beta, and interferon gamma.The VP24 and VP35 structural proteins of EBOV play a key role in this interference. When a cell is infected with EBOV, receptors located in the cells cytosol (such as RIG-I and MDA5) or outside of the cytosol (such as Toll-like receptor 3 (TLR3), TLR7, TLR8 and TLR9) recognise infectious molecules associated with the virus. On TLR activation, proteins including interferon regulatory factor 3 and interferon regulatory factor 7 trigger a signalling cascade that leads to the expression of type 1 interferons. The type 1 interferons are then released and bind to the IFNAR1 and IFNAR2 receptors expressed on the surface of a neighbouring cell. Once interferon has bound to its receptors on the neighbouring cell, the signalling proteins STAT1 and STAT2 are activated and move to the cells nucleus. This triggers the expression of interferon-stimulated genes, which code for proteins with antiviral properties. EBOVs V24 protein blocks the production of these antiviral proteins by preventing the STAT1 signalling protein in the neighbouring cell from entering the nucleus. The VP35 protein directly inhibits the production of interferon-beta. By inhibiting these immune responses, EBOV may quickly spread throughout the body. Diagnosis
When EVD is suspected, travel, work history, and exposure to wildlife are important factors with respect to further diagnostic efforts.
In the United States, the CDC recommends that restrictions on public activity, including travel restrictions, are not required for the following defined risk levels:
having been in a country with widespread Ebola disease transmission and having no known exposure (low risk); or having been in that country more than 21 days ago (no risk)
encounter with a person showing symptoms; but not within three feet of the person with Ebola without wearing PPE; and no direct contact with body fluids
having had brief skin contact with a person showing symptoms of Ebola disease when the person was believed to be not very contagious (low risk)
in countries without widespread Ebola disease transmission: direct contact with a person showing symptoms of the disease while wearing PPE (low risk)
contact with a person with Ebola disease before the person was showing symptoms (no risk).The CDC recommends monitoring for the symptoms of Ebola disease for those both at "low risk" and at higher risk. Laboratory
In laboratories where diagnostic testing is carried out, biosafety level 4-equivalent containment is required. Laboratory researchers must be properly trained in BSL-4 practices and wear proper PPE. Isolation
Isolation refers to separating those who are sick from those who are not. Quarantine refers to separating those who may have been exposed to a disease until they either show signs of the disease or are no longer at risk. Quarantine, also known as enforced isolation, is usually effective in decreasing spread. Governments often quarantine areas where the disease is occurring or individuals who may transmit the disease outside of an initial area.