Ebola Virus is one of the deadliest viruses known to man, with no proven medication & no vaccines till date; the disease has a 25% to 90% mortality rate among humans. Largely native to Central Africa & Sahara, the latest outbreak of the EVD (Ebola Virus Disease) in The Republic of Congo since March 2014 has reportedly killed about 12,000 people out of about 29,000 infected. The Ebola Virus is part of the Filoviridae family consisting of three genera – Cuevavirus, Marburgvirus, and Ebolavirus. As on date, virologists have identified five species – Zaire, Bundibugyo, Sudan, Reston and Taï Forest. The Sudan & Zaire are mainly responsible for the large outbreaks with the latest one in March 2014 caused by the Zaire strain. African countries of Liberia, Guinea & Sierra Leone, are the ones most affected, with low-to-none health infrastructural presence.
Origins & Disease Transmission
The first cases were discovered in 1976 at Nzara (South Sudan) & Yambuku (Democratic Republic of Congo). The latter outbreak occurred near the river Ebola, from where the virus’ name derives. The Pteropodidae family of bats, commonly known as fruit bats, is known to be the natural host of the Ebola virus. The virus is then introduced into the human population through close contact with the body fluids, blood & other organs of the infected animals’ remains which generally remain unattended. Animals like gorillas, antelopes, bats, monkeys get infected primarily resulting in the ultimate spread of the disease in humans.
Once a human is affected, the virus then spreads rapidly through the population by proximity contact with the body fluids and secretions of the infected person or from the used bedding, clothes, and medical appliances. Often the health & medical workers are also infected because the necessary precautions while treatment was not observed strictly.
Even during burial process, where the patient’s body comes in contact with others’ of the populace, there is a high probability of infection. The gestation period of the virus is 2 to 21 days, and the people are infectious when they start to exhibit symptoms of EVD, & remain so until the virus remains in the bloodstream.
After the person is infected, the symptoms include sudden onset of fever, body fatigue, headache, muscular pain & sore throat. Followed by this occurs diarrhea, vomiting, skin rashes, impaired liver and kidney function & some extreme cases, internal & external bleeding of gums & blood in the stool. Laboratory tests have found low platelet & WBC counts, & heightened liver enzyme secretions.
Early diagnosis is sometimes difficult, as the symptoms are similar to Meningitis, Malaria and Typhoid fever. The following laboratory investigations are required to ascertain Ebola virus infection–
- Electron Microscopy
- (RT-PCR) Reverse Transcriptase Polymerase Chain Reaction Test
- Antigen-Capture & Detection tests
- Antibody-Capture Enzyme-Linked Immunosorbent Assay (ELISA) test
- Serum Neutralization test
- Isolation of Virus through Cell Culture
Great care must be taken with all such samples from infected patients; as they are an extreme Biohazard risk. Maximum protection is needed while handling these specimens & proper procedures need to be observed even during disposal.
Supportive care with intravenous & oral fluids is given to patients – as yet there is no specific proven treatment for EVD. Symptomatic treatment of specific bodily disorders improves survival rate. A range of immune, drug & blood therapies is currently undergoing trials, along with some human testing for vaccines.
Prevention & Control
Prevention largely relies on community education & engagement, safe burial grounds & tracing of the viral contact points along with a good laboratory service capable of handling highly infectious samples efficiently. Raising awareness in the community of preventive measures that an individual can take is a simple yet effective way to reduce human transmission. Some points to note are–
- Reduce Wildlife to Human Transmission – finding the infected animals’ & handling them with appropriate protection & proper disposal is required. Avoid eating fruits & raw animal products in the vicinity; & consume thoroughly cooked meals.
- Reduce Human-to-Human Transmission – Avoid direct or close contact with the infected patients, particularly with their body fluids, secretions & personal items like clothing, beds, etc. Sexual contact is also discouraged as the virus may gestate up to 3 months in the body fluids of the once-infected person & multiple testing is required before declaring a person’s infection-free.
In a nutshell, the Ebola family of viruses is some of the most contagious pathogens known to man. Since no effective direct countering medication or vaccine is available till date, the utmost focus should be on providing proper medical support to the infected while taking all the necessary precautions so that there is no further outbreak of the disease. Only by collective education, community cooperation & support can this dreaded viral disease be prevented & controlled.