Ebola Outbreak: Causes, Characteristics, Methods Of Detection, And Findings In Africa

Background

The Ebola outbreak disease is a deadly disease that has affected a wide population all over the world, mainly from the Democratic Republic of the Congo and Sudan in Africa. The source of contamination of virus is through the close contacts of the wild animals, mostly from primates that have already been infected from the viral disease.

 The transmission/ exposure of Ebola virus spreads from the blood and other bodily fluids of the primates such as bats, as these primates are utilized as the food source in many counties. Although Ebola virus was not able to infect humans, the several times person-to-bat transmission led to the spill over events that started causing diseases in humans too. The route of transmission of Ebola virus from person to person occurs through blood, body fluids, direct contact with clothes or body of infected person and through injected objects such as needles. WHO has recorded a total of 11323 west African people have died to date from the Ebola outbreak (Leligdowicz et al., 2016).

Among five known species of Ebola virus, four species can infect humans. The first outbreak of Ebola virus (as EBOV) occurred in south-eastern Guinea. However, later outbreak of (Zaire Ebolavirus species occurred with higher transmission rate in other regions of West Africa. The transmission of Zaire Ebolavirus species was much faster than the previous outbreak and 50-80% more challenging than the previous outbreak (Feldmann & Geisbert, 2011). The Zaire Ebolavirus species is known as the largest outbreak in west Africa history that occurred in year 2014. However, the epicentre of the transmission of EVD is known to be Sudan, where transmission occurred in year 2004 and caused infection in 17 people.

Characteristics of virus: Ebolavirus belongs to the family of Filovieidae and order Mononegavirales. Ebola virus is of filamentous shape with some strains of circles and of U shaped. The known viral particle of virus consists of filovirus virions that compose an envelope of 80 nm and contain negative-strand RNA. The high fatality rate of the infection caused viral haemorrhagic fever with plasma leakage. The common symptoms of Ebola virus disease are severe headache, joint pain, developing skin rashes, diarrhoea, vomiting, and impaired functions of kidney & liver, weakness & fatigue and sore throat. However, the insufficient facility of treatment in hospitals also led to a significant increase in the disease cases as the hospital workers had to be in close contact with the patients.

Transmission of Ebola Virus

the two consecutive fatal haemorrhagic illness causing fever were first recorded in the year 1976 in central Africa. Approximately 30,000 people were supposed to be affected by the serious illness of the Ebolavirus outbreak, out of which 12,000 patients died because of no cure and applicable treatment. Hence, WHO declared the outbreak as an emergency international concern to initiate the assessments to reduce the outbreak symptoms.  The retrospective study of Liberia and Sierra Leone represents the collected data of 5 Ebola treatment units (ETUs) of the epidemic. The symptoms take 2 to 21 days to appear. The epidemiological data is collected from the patient care centres, which are categories based upon the low or high-risk zone. Sampling is done to make the confirmation input the data quality of the outbreak; The investigated outbreak clinical trial is taken for patient triage procedure.

The 5 strains of Ebolavirus of Liberia and Sierra were managed to be treated by international medical corps (IMC). The patients that were cared under IMC were counted as 2,500 over 1 year of operation. Overall case fatality ratio of the patients was 57 percent for EVD positive patients while 8.1 % for the EVD negative patients possessing the significant symptoms of diarrhoea, red eyes, and funeral attendee. Multiple transporting agencies including government and private were received at ETU. The tests were confirmed through the laboratory screening. The research team collected and analyse the clinical results to inform the responses of the studies and maintain the quality for the future epidemics. The diagnosis of the virus can be made only after the arrival of the symptoms, as in absence of symptoms, if someone gets the test done, the pseudo positive results can also get because of the occurrence of other infectious agents in body. The Viral RNA or antibodies of the viral particle can be detected through the tissue culture. However, to detect the specific disease-causing agent can be done through enzyme linked immunosorbent assay (or ELISA). The diagnostic methods of detecting virus are ELISA that detects specific antibodies (IgG and IgM) immunoglobins (Rewar and Mirdha 2014). The purpose of the formation of different tests in laboratories is to identify the

In Port Loko and Bombali districts of Sierra Leone, EVD testings were performed under public health England (PHE) laboratory. The tests were performed through the RT-PCR, where a gene target (EBOV locus) was analysed for the confirmation of the test. The instrument utilized for the detection of viral presence was done through the in-house Trombley assay (Weller et al., 2016).

Characteristics of virus

The other laboratory, which also performed several tests to diagnose the availability of Ebolavirus in patients’ sample, was the Naval Medical Research Centre (NMRC) laboratory of America. NMRC laboratory utilized the Applied Biosystems Step OnePlus instrument to perform the tests by searching two gene targets of the virus (EBOV locus and minor groove binding locus). However, some of the other patients that left from NMRC and PHE laboratory were tested through the government-managed holding centres (Weller et al. 2016).

There is no record of the new outcomes of the outbreak in year from 1979 to 1994. On the contrary, in year 2014 and 2016, the largest outcomes with over 28000 cases have recorded in West Africa. The most affected species were Sierra Leone, Guinea, and Liberia. In the Guinea pig, the affected viral strain was Reston virus (or RESTV). Most cases were recorded in tropical rainforests and the nearly associated remote villages of West Africa such as Sudan, Uganda, and the Democratic Republic of the Congo. However, the understanding of the view of disease and the previous disease’s recommendation has enabled the rapid health responses of the people (Shears and O’Dempsey 2015).

Year	Country	Ebola virus species	Cases	Deaths	Case fatality rate
1976	Zaire (Democratic Republic of Congo)	Zaire	318	280	88%
1976	Sudan	Sudan	284	151	53%
1977	Zaire (DRC)	Zaire	1	1	100%
1979	Sudan	Sudan	34	22	65%
1996	Gabon	Zaire	31	21	57%
1996	Gabon	Zaire	60	45	75%
2001-2	Gabon and Republic of Congo	Zaire	124	97	78%
2002-3	Republic of Congo	Zaire	143	128	89%
2008-9	Democratic Republic of Congo	Zaire	32	14	47%
2011	Uganda	Sudan	1	1	100%

https://www.gov.uk/government/publications/Ebola-origins-reservoirs-transmission-and-guidelines/Ebola-overview-history-origins-and-transmission#:~:text=The%20first%20human%20case%20in,Republic%20of%20Congo%20and%20Gabon

In year 2019, the portable and confirmed cases of Ebolavirus have demographically distributed in three main zones of Africa, which are the Democratic Republic of the Congo (DRC), Ituri Provinces, and North & South Kivu. In the year 2019 June, three infected people of the same family who travelled from Uganda to DRC showed significant contamination from infections. The infected people died after some time when they returned to Uganda. The first case of Ebola reported in year 2019 after traveling of 3 infected people was reported in Goma in July. However, the second case was also reported in Goma at the end of July. Then, the medical centre of Ebola treatment initiated the treatment and care for the suspected patients.

After the laboratory diagnosis, Ebola WHO developed the standard treatment protocol for the care and treatment of the positive patients. The treatments were performed by the nurses, hygienists, physicians, psychologists, health officials and other healthcare facilities. The nursing staff visited 1-2 times a day to the patients with lower illness to the infections. However, for severe illness or major symptoms, staff used to round 4-5 times a day (World Health Organization 2014). 

Declaration of public health emergency: In year 2019, the Ebolavirus outbreak was declared as an emergency case by the director of WHO, Dr. Tedros Adhanom. Dr. Tedros Adhanom was concerned for the health system of DRC and suggested taking the noticeable and redoubling efforts. In order to reduce the outbreak, hard and extraordinary works are required to be done, which can be helped not only by government but also need the assistance of communities, public and political members. For the purpose of reducing the outbreak, a meeting was also held in DRC, named the International Health Regulations Emergency Committee. The committee focused on the recommendations and development of the outbreak prevention methods, in which Goma (a district of DRC) with two million people taken into consideration. Moreover, the funding issues to avoid the trade and travel restrictions, as the punitive economic consequences were discussed in of the recommendations was to help the people by minimizing the illness and not the panelise or stigmas people related to the outbreak interruptions (World Health Organization 2019).

Methods being implemented to collect information about the Ebola virus in West Africa

Providing clinical care has proven the counter stone in managing the patient’s illness and spread of the disease. The clinical care consists of providing nutritional support, maintaining the electrolyte balance, blood pressure, oxygen status of the patient and hydration. Additionally, patients were supported with antidiarrheal agents, antiemetics and other medications, which are effective in managing the fever fatigue, and stopping the occurrence of secondary bacterial infections. Such clinical trials have proven effective and successful in controlling the worsening condition of the outbreak in Congo (Martínez et al., 2015).

Moreover, clinical trials conducted to manage the EVD resulted in developing the drugs; REGN-EB3 and mAb114. The drugs provided effective survival rates to infectious diseases. mAb114 was developed by the National Institute of Allergy and Infectious Diseases, whereas REGN-EB3 was developed by Regeneron Pharmaceuticals. Both the drugs are considered to be the hope for the future. Although eh evidence is not clear ad confirmed because of the large biodiversity in the African forests ecosystems that form the puzzle in maintaining the potential hosts (Caron et al. 2018).

The interpretation of the data of the Ebola outbreak is based on the severity of the pathophysiology, which can be measured through the collected data. After the collection of the data, treatment of the patients is planned based upon their condition. Moreover, interpretation involves the treatment, cure and prevention methodologies of the outbreak to minimize the effects of the illness and reduce the chances of encountering in the future.

Pathophysiology of EVD is associated with end-organ dysfunction Ing and bacterial sepsis, affecting the host immune response. The strain EBOV binds with the immune cells, including macrophages and dendritic cells that spread in liver, spleen and the lymphatic system to spread the infection all over the body. Moreover, abortion can result in the pregnancy, if a woman is affected by the Ebolavirus illness (Fletcher et al. 2014).

The clinical laboratory data collection is used as the patient’s disease investigation, which is further determined for the [process of treatment.  The technologies other than ELISA, and RT-PCR, such as blood sampling through haematological and biochemistry parameters are also used in the international laboratories to characterize the course of the illness. Piccolo Xpress® is one of the famous Ebola treatment facilities recognised to treat the severity level of Ebolavirus. Piccolo blood chemistry analyser analysed the blood sample, whereas other instrument, Abasis (Comprehensive Metabolic Reagent Discs) trends to determine the metabolic measurements of body nutrients of the body to know the level of severity of patient’s condition. The nutrients include CO2, N, alkaline Phosphatase, alanine aminotransferase, bilirubin, albumin, and blood urea nitrogen (Schieffelin et al. 2014).

Findings of outbreak in different regions of Africa

Prevention and control measures of infection: Infection prevention and control (IPC) also established various clinical adjustments for the prevention and cure of the outbreak. The private rooms provided to the patients with the availability of adjustable beds, intravenous drips, medical staff, haemodialysis, mechanical ventilation, urinalysis, blood gas measurements and monitors. The illness can cause the reduction in clotting factors concentrating the products that lead in fibrin degradation, which eventually result in bleeding and inflammation (Leligdowicz et al. 2016).

The clinical centre of infection prevention and control has shown the concern about the EBOV illness and transmission and established some of the safe and preventive measures, such as using gloves, washing hands, protecting mucous membrane and donning of personal protective equipment (PPE), and the use of face shield or medical masks. The professional and public attention towards the experimental interventions were captured by the effective human clinical trials that utilise the efforts, designs, safety and efficacy of the dosing data. The clinical trial was intended to treat the spread of the infection and minimize the effects of the illness. Nurses or healthcare providers which are required to enter into the contaminated zone need the use of full personal protective equipment. Furthermore, the strategies also include education. Education is the way of making people aware of the signs, symptom and concern of the disease. For the successful intervention of education to the public, involvement of health education and local leaders is necessary to emphasize the education (World Health Organization 2019).

The data collection and the sampling procedure need to take the consent from the committees including Sierra Leone Ethics and Scientific Review Committee and Tulane University. The committees have approved the review of the biosafety protocols. The biosafety protocols include patients’ medical tests, reports, metabolic findings, and descriptive analysis of the patient’s condition. For example, metabolic diagnosis is a result of elevated measurement of the body nutrients, urea, creatinine, and co2 level in the Ebola-infected patients. Moreover, in the Ebola-positive patients, vital changes can be seen in approximately 6 hours, which include the elevated temperature. The higher the temperature, make the more chances of a patient’s condition to go worsen (Schieffelin et al. 2014).

References

Caron, A., Bourgarel, M., Cappelle, J., Liégeois, F., De Nys, H.M. and Roger, F., 2018. Ebola virus maintenance: if not (only) bats, what else?. Viruses, 10(10), p.549.

Feldmann, H., and Geisbert, T. W. 2011. Ebola haemorrhagic fever. The Lancet, 377(9768), 849-862.

Fletcher, T.E., Fowler, R.A. and Beeching, N.J., 2014. Understanding organ dysfunction in Ebola virus disease. Intensive Care Medicine, 40(12), pp.1936-1939.

Formenty, P. (2014). Ebola virus disease. In Emerging Infectious Diseases (pp. 121-134). Academic Press.

Gebretadik, F. A., Seifu, M. F., and Gelaw, B. K. 2015. Review on Ebola virus disease: its outbreak and current status. Epidemiology (sunnyvale), 5, 1-8.

Leligdowicz, A., Fischer, W. A., Uyeki, T. M., Fletcher, T. E., Adhikari, N. K., Portella, G., and Fowler, R. A. 2016. Ebola virus disease and critical illness. Critical Care, 20(1), 1-14.

Martínez, M.J., Salim, A.M., Hurtado, J.C. and Kilgore, P.E., 2015. Ebola virus infection: overview and update on prevention and treatment. Infectious diseases and therapy, 4(4), pp.365-390.

Rewar, S., and Mirdha, D. 2014. Transmission of Ebola virus disease: an overview. Annals of Global Health, 80(6), 444-451.

Schieffelin, J.S., Shaffer, J.G., Goba, A., Gbakie, M., Gire, S.K., Colubri, A., Sealfon, R.S., Kanneh, L., Moigboi, A., Momoh, M. and Fullah, M., 2014. Clinical illness and outcomes in patients with Ebola in Sierra Leone. New England journal of medicine, 371(22), pp.2092-2100.

Shears, P., and O’Dempsey, T. J. D. 2015). Ebola virus disease in Africa: epidemiology and nosocomial transmission. Journal of Hospital Infection, 90(1), 1-9.

Weller, S.A., Bailey, D., Matthews, S., Lumley, S., Sweed, A., Ready, D., Eltringham, G., Richards, J., Vipond, R., Lukaszewski, R. and Payne, P.M., 2016. Evaluation of the Biofire FilmArray BioThreat-E Test (v2. 5) for rapid identification of Ebola virus disease in heat-treated blood samples obtained in Sierra Leone and the United Kingdom. Journal of Clinical Microbiology, 54(1), pp.114-119.

World Health Organization, 2014. Clinical management of patients with viral haemorrhagic fever: a pocket guide for the front-line health worker: interim emergency guidance-generic draft for West African adaptation 30 March 2014 (No. WHO/HSE/PED/AIP/14.05). World Health Organization.

World Health Organization, 2019. Ebola outbreak in the Democratic Republic of the Congo declared a public health emergency of international concern. Press Release, 17.