Ebola Virus: A Bug out of Control?
Ebola virus outbreak has now become a major topic in West African Countries. Some of the countries in Africa that had reported Ebola infection include Guinea, Liberia, Sierra Leone, DR Congo, Gabon, South Africa and Uganda. Several reports have surfaced regarding the incidence of the infection. A major concern is those of fruit bats that are loose in those regions that are carriers of the virus but are resistant to the impact of the organisms. Why is this outbreak not under control? Are those fruit bats captured and killed for meat? Are they kept as pet? Are they transported from one country to another within West African Countries? Yes, these are necessary questions beside human to human transmissions.
Ebola virus was discovered by a Belgian Scientist Professor Peter Piot. He helped identify Ebola virus in Belgium when he was sent a blood sample from a Catholic nun who had died in a country now known as DR Congo. As mentioned above, bats are considered the most commonly identified reservoirs for Ebola virus. These bats have been reported to have been smoked, grilled or made into spicy food.
Viral Structure and Infection Process
Ebola virus particles are filamentous particles that may appear in the shape of a shepherd's crook or a "U" or a "6", and may be branched or coiled or tocoid . They vary in length but normally 80nM in length. Overall, the median particle length of Ebola viruses ranges from 974 to 1,086 nm, but may reach 14,000 nm in a tissue culture.
The method of transmission of Ebola virus involves consumption of partially infected fruits dropped by infected bats, Human to Human transmission through bodily fluids, reuse of needles from infected persons etc. Prior to attaching on human cell membrane, Ebola virus first binds to a protein known as cholesterol transporter protein NPC1.
NPC1 is an essential protein for Ebola virus infection. By binding on this protein, the virus is able to gain entry in human cells and is also able to replicate. NPC1 was shown to be important for cellular entry of Ebola virus because it mediates infection by binding directly to the viral glycoprotein.
The process of replication is a concern that can complicate the infection. Generally, replication involves the duplication of an existing viral organism. When Ebola virus makes copies, the copies of viruses are able to infect other cells. The infection can then cause damages that affect organs such as liver. Ebola virus replication exceeds protein synthesis of infected cells and host immune defenses. The presence of viral particles and cell damage resulting from budding causes the release of cytokines which are the signaling molecules for fever and inflammation.
Signs and Symptoms of Ebola Virus Infection
There are a number of signs and symptoms associated with Ebola virus infection. These are as follows: Fever, headache, joint and muscle aches, diarrhea, lack of appetite, weakness, diarrhea, vomiting etc. On the other hand, some patients may present with cough, rash, hiccups, chest pain, and difficulty breathing. The time frame in terms of symptom presentation may vary from 2 to 21 days. Generally, about 7 to 10 days is regular. People who are affected often bleed and vomit. They may also face kidney failure as well as death if the infection got worse.
Ebola Virus Survivor
It has been clearly stated that there is no definite cure or vaccine for Ebola virus infection. However, a number of remedies have been used, waiting to be tried or experimented on. Most of the standard treatment requires supportive care like fluid replacements. Bleeding problem is addressed with giving fresh blood or platelets. Treatment can also involve administration of anticoagulants early in infection to prevent or control disseminated intravascular coagulation, maintaining oxygen levels, pain control, and administration of antibiotics to treat secondary infections. Some other treatments that have been tried experimentally in mice involved the use of clomiphene, a fertility drug and a cancer drug, toremifene. It showed some promising results. Experimental serums from the blood of Ebola infection survivors have been tried. An important area of discovery or research I would like to mention is the use of antibodies directed against NPC1, a cholesterol transporter protein. Ebola virus require this protein for cellular binding, cellular entry and replication. By restructuring or inactivating this protein, I would think it should reduce chances of Ebola virus attachment in the human body. A number of companies including Thermo Fisher, and Novus Biologicals currently produce NPC1 antibodies. The implication of this in the human body is yet to be investigated.