History of Ebola Virus Disease and Its Treatment

Viruses are living microorganisms bounded by a cellular protein membrane containing genetic material. The genetic material can be either DNA (deoxyribonucleic acid) or RNA (ribonucleic acid), which helps with the transmission of new generations. Viruses are parasitic and therefore, need a healthy host body to sustain themselves. 

The Ebola virus is a deadly viral disease that has been reported in African countries and is marked by symptoms such as haemorrhage, fever, weakness, etc. The outbreak occurred in western Africa between 2013 to 2016. New Ebola virus strains have been identified in the Democratic Republic of Congo in April 2022. 

History of Ebola 

Ebola virus is an RNA virus, belonging to the filovirus family and mostly affects humans and primates (monkeys, etc.). Ebola was first reported in the year 1976 on the shores of the Ebola River (currently the Democratic Republic of Congo) and in Sudan with subsequent periodic reappearances. 

No new occurrences of Ebola virus strains were observed between 1970 to 1994. Nonetheless, since then, there has been an increase in the number of cases. By far, the largest transmission of Ebola virus occurred between 2014 to 2016, affecting Liberia, Guinea, and Sierra Leone. During this period, over 29,000 cases were reported. To date, 6 strains of Ebola viruses have been identified by the scientists, out of which 4 have been known to affect humans. These 4 strains are as follows:

• Zaïre ebolavirus (EBOV)
• Tai Forest (TAFV) (also known as Ebola Ivory Coast)
• Sudan ebolavirus (SUDV)
• Bundibugyo ebolavirus (BDBV)

Natural reservoir

The studies have revealed Ebola virus is a zoonotic virus. A zoonotic virus refers to those viruses that can spread illness from non-human sources (animals) to humans. However, the prime natural reservoir had not been detected. However, a recent publication from WHO mentions fruit bats as the natural hosts. 

Transmission of Ebola

The transmission of Ebola virus happens due to contact with body fluids. The first human infection was reported to be through blood contamination. Ebola infection also spreads from an infected person to a healthy one through other body fluids such as secretory fluids. Therefore, Ebola is only contagious if there is direct contact with an infected person. It doesn’t spread through air, food, or water. 

There have been instances of the Ebola virus in breastmilk. As a result of which, pregnant women recovering from Ebola need their breast milk tested to check for further transmission into the newborn. 

Symptoms

The early strains of Ebola showcased milk flu-like symptoms; however, the scenarios have changed. As the virus adapts to external environmental factors, the infected symptoms are also changing. The incubation period, i.e., the period between virus infection and onset of symptoms, roughly ranges from 2 to 21 days. Following are the symptoms of Ebola virus. 

• Fever
• Headache
• Sore throat
• Muscle cramps and pain
• Fatigue and weakness
• Vomiting
• Diarrhoea
• Skin rash
• Organ failures 
• In extreme cases it leads to haemorrhage. 
• Low platelet and WBC counts
• Impaired liver enzyme functions, and so on. 

Diagnosis

The following diagnosis methods are followed.

• ELISA test
• Antigen-capture detection test
• Serum neutralisation test
• Reverse transcriptase-polymerase chain reaction (RT-PCR) assay

The WHO recommended tests are:

• Nucleic acid tests (NAT)
• Rapid antigen test.

Treatment

There is no specific treatment process for the Ebola virus. During the outbreak in the Democratic Republic of Congo, the multi-drug randomised control trial was initiated to evaluate the effectiveness of a large number of drugs. Two dug treatments have been extensively used in recent times. Inmazeb and Ebanga, are two monoclonal antibody injections given to Ebola patients that helps to block the cell receptors and thereby prevents their entry into the system.

Other symptom management adopted by doctors include:

• Oral rehydration
• Oxygen supply
• Blood transfusion, and so on.

Vaccine

The Ervebo vaccine has shown a certain degree of effectiveness in controlling the spread of Zaire ebola virus strain transmission in humans. However, a vaccine particularly designed to cure this disease is yet to be discovered. 

Conclusion

Ebola, being an epidemic poses a great threat of becoming a pandemic infection. The best way to stop the transmission of Ebola is by restricting travel to Ebola-infected regions. Moreover, limiting contact with bats, chimpanzees, monkeys, etc. checks the further spread of this disease. Frontline workers need to get vaccinated along with taking proper measures such as wearing gloves, masks, face shields, etc.