Ebola: Causes, Symptoms & Treatment

Abstract 

Ebola also called hemorrhagic fever has always been a global menace since its discovery in the Democratic Republic of Congo in 1976. The disease has a very high mortality rate of up to 90%. Since the discovery of the disease, five species have been identified which include Tai Forest ebolavirus, Bundibugyo ebolavirus, Reston ebolavirus, Sudan ebolavirus, and Zaire ebolavirus. The mortality rate changes depending on the species, but ranges between 40-90%. The Public Health Emergency of the International Concern declared that Ebola Virus requires collaboration between nations to control the global menace since the outbreak in West Africa in 2014. Ebola virus is a high-risk disease that requires high containment measures to minimize the cases of infections in the populations. 

Additionally, high-quality training is necessary among the healthcare workers to protect them from the virus, in which they also understand the importance of personal protective equipment in the fight against the disease. There have been many outbreaks of the Ebola Virus since its discovery in 1976, with countries located on the West African Coast such as Liberia, Sierra Leone, and Guinea recording the most severe and largest outbreak of the disease. The hemorrhagic fever has an incubation period that ranging between 2 to 21 days, in which the patient manifests flu-like signs, which later progress to shock, bleeding, and various organ failures. Currently, Ebola disease lacks specific treatment, hence the need to avoid contact with contaminated body fluids, and increased hand hygiene especially when near people that have the condition. High-risk individuals such as the health professionals that are in direct contact with the infected parties need to wear protective equipment and adopt measures that ensure their safety. 

Background Information about the Pathogen and the Disease 

In the past decade, Ebola disease cases have been continuously reported. According to Rajak et al. (2015), Ebola is a zoonotic disease that is transmitted through direct contact with an infected dead or live animal. Ebola disease remains a global challenge since its discovery in 1976. Ebola disease is an acute viral condition that is characterized by high fever that is followed by intense bleeding among non-human and human primates (Sukul et al., 2016). Ebola virus causing the Ebola disease belongs to the genus. Ebola virus is classified into the following classes, Bundibugyo Ebolavirus, Tai Forest Ebolavirus, Sudan Ebolavirus, Zaire Ebolavirus, and Reston Ebola Virus (Pacheco et al., 2015). The amino acid sequence in the ebolavirus species is responsible for the noted differences. 

Ebolavirus species originating from Africa include Tai Forest, Sudan, Zaire, and Bundibugyo. However, Reston Ebola Virus was discovered in Asia in monkeys in which it was moved to a quarantine unit in 1989, in the US (Pacheco et al., 2015). Most cases of Ebola virus diseases are caused by Sudan and Zaire Ebolavirus. According to Pacheco et al. (2015), Bundibugyo, Sudan, and Zaire Ebolavirus are associated with the major outbreaks of the Ebola disease, with mortality rates ranging between 40 t0 90%. Bundibugyo Ebola virus has the lowest recorded mortality rates among humans of 40%, while the Zaire Ebola Virus has the highest mortality rate of 80 to 90% (Pacheco et al., 2015). Currently, there is only a single case of infection associated with the Tai Forest Ebola Virus, among humans and it is not fatal. 

Signs and Symptoms of the Ebola Disease 

Ebola is a zoonotic disease that is transmitted to people through direct contact with an infected animal's body fluids or flesh. Pacheco et al. (2015) indicate that a fruit bat is an Ebola Virus's natural reservoir. Unlike other animals, the bat can be infected and spread the ebola disease without being affected by it. Generally, the natural hosts for the Ebola virus are wild animals such as baboons, chimpanzees, African green monkeys, which spread it to humans. Zaire Ebolavirus has been discovered to cause the Ebola disease in domestic animals such as pigs and dogs but incapable of causing any serious effects, thus it can be easily transmitted to humans. Ebola virus is transmitted to humans through direct contact with infected people’s bodily fluids such as mucus, saliva, sweat, tears, urine, semen breast milk (Burd, 2015). Arthropods, birds, and plants, are also highlighted as potential reservoirs of the Ebola virus (Singh et al., 2017). There is a high chance of contracting the Ebola virus if one comes into contact with the body fluids of an individual at the later stages of the disease. Additionally, people contract the Ebola virus indirectly by coming into contact with the environment that has been infected with the body fluids of an individual with the disease. 

There is a difference in harshness between the various Ebola virus species. According to Rajak et al. (2015), the Zaire Ebolavirus is the most severe of all the viruses, with a mortality rate of almost 90% (Kimura et al., 2015). Zaire Ebolavirus has an incubation period of 2-21 days, in which an individual exhibits symptoms such as fever which is accompanied by fatigue, headache, sore throat, abdominal pain, myalgia, vomiting, nausea, cough, diarrhea, and dysphagia (Beeching, 2014). Early clinical signs associated with Ebola virus disease include a conjunctival infection, in which patients also portray tachypnea, hiccoughs, shock, and bleeding in some patients. In white patients, a dermatological indicator is a maculopapular rash on their trunk. Goeijenbier et al. (2014) indicate that people with the Ebola virus have a variety of neurological signs such as delirium, convulsions, and coma. In normal cases, people die six to nine weeks after portraying the signs and symptoms of an Ebola Virus. However, there exist differences in the death rates during and in between an epidemic. For the patients that survive the disease, there is a possibility of gradual improvement in their body functions, which is characterized by arthralgia and fatigue (Munoz-Fontela & McElroy, 2017 ) . Therefore, by analyzing the signs and symptoms of the Ebola virus disease there is a possibility of the condition mimicking other tropical diseases such as yellow fever, and malaria. 

Description of the Ebola Virus 

Zaire Ebolavirus is responsible for most of the outbreaks in different parts of the world. Zaire Ebolavirus is in the family Filoviridae and order mononegavirale , meaning it is non-segmented, single-stranded, and has a negative-sense RNA virus. Zaire Ebolavirus is in the genus Ebolavirus. Ebolaviruses are RNA viruses that are negatively stranded and linear, which have a genome of about 19 kilobases in length. It also has seven genes. The seven open frames envelopes glycoproteins. After one is infected by the Ebola Virus the development of the disease depends on the environment, host, and the virus. The Ebola Virus disease affects both the human and non-human primates. According to Rajak et al. (2015), the different species of the Ebola virus invade the human body through injuries, abrasions, and mucosal surfaces in an individual's skin. In other cases, the Ebola virus can be directly transmitted from the mother to the child. 

The Ebola Virus lifecycle starts when the virus enters the cell of the host through binding to the co-receptors or receptors in the pathway of the micropinocytosis. According to Yu et al. (2017), a variety of mechanisms in the Ebola Virus lifecycle remains unclarified and unclear. For instance, in the uncoating and fusion stage, the proteolytic cleavage together with other unidentified factors is responsible for triggering the nucleocapsids uncoating in the endosome (Hoenen et al., 2019). Additionally, in the uncoating and fusion stage, there is a fusion of the cellular membranes and the Ebola Virus. Transcription and replication involve functions such as transcribing of mRNA and translation of the viral proteins. Additionally, the transcription and replication stage involves also the replication of the viral genome. In the assembly and budding stage, the nucleocapsids initiate the assembly, in which they gather at the perinuclear region, in which they are then moved to the plasma membrane where budding takes place. Additionally, budding also occurs at the late endosomes and in intracellular membranes. 

Pathogenesis of the Infection 

By entering through the skin, the Ebola virus access, monocytes, macrophages, and dendritic cells which move the disease further to the host's liver, spleen, and lymph nodes. The monocytes and macrophages that are stimulated by the Ebola virus release a cytokine storm that destroys blood vessels and ones' tissues. In most cases, death from the Ebola virus results from coagulation or loss of blood. According to Wambani et al. (2015), coagulopathy results from the damage on the clotting factors, thrombocytopenia, and unavailability of the anticoagulant protein C. The blood vessel damage to an individual leads to renal failure and intravascular coagulation. In the fight against the Ebola virus, the body produces antibodies, which then bind with C1q, and move to the macrophages and dendritic cells binding sites, whereby they destroy the cells. 

Recent Research Study on Ebola Virus Disease 

The qualitative study by Kodish et al. (2016) sought to bring an understanding of how the Ebola disease outbreak in 2014-2016 impacted nutrition in Sierra Leone. The research sought to apply the findings as a framework for informing response strategies in future epidemics. The dependent variable in the study is nutrition, while the Ebola virus disease is the independent variable. One of the control factors in the study is movement restriction, such as 21-day quarantine, similar to those implemented in large-scale disasters to ascertain whether there are any effects on trade, retailing, and distribution of the foods. The control group is FOCUS 1000 team members who experienced the Ebola outbreak and are meant to confirm the changes explained by people are an outcome of the Ebola virus impact. 

The data gathering process involved interviewing participants, which were carried out in two phases. Information gathered in either of the phases sought to reach a point of data saturation, in which people would no longer introduce key themes. 

Figure 1: A summary of the Two Phases in the Process of Gathering information in the Ebola Research Study 

Phase 1 of the Interview process  Questions used in this phase were chosen from reviewed literature, an agreement between FOCUS 1000 team members and UNICEF. Groups involved in the interview are key informants, government policymakers, hospital management, non-governmental organizations, and program staff agency, who gave information about their own experiences as well as the organizations they represent.  Phase 2 of the interview process  This phase involved community informants, including front-line health workers, and community leaders, who were allowed to speak of their individual lived experience during the Ebola virus spread.

Courtesy: (Kodish et al., 2019) 

Figure 2 : A Table Summarizing the Nutrition-related Impacts of Ebola Virus Spread 

Sectors	Nutrition-Related Impact
Food Production	Reduced workforce mobility, movement restriction, and the migration of people to safe areas affected the domestic agriculture
Storage and Food Processing	Less food production led to little storage of foods
Retailing of foods	Few markets were in operation due to market closures and restricted movements
Trade and Food distribution	Closed roads and few agricultural activities led to reduced food distribution

Courtesy: (Kodish et al., 2019) 

Information gathered led to the conclusion that the Ebola virus impacted the whole process of the food value chain, which negatively affected households, individuals, and the whole population's nutrition status. The negative effects in the value food chain were a result of the disease containment measures, outbreak consequences, and the clinical manifestation of the epidemic itself. Therefore, government acts of imposing quarantines, and blocking roads in Sierra Leone negatively impacted nutrition and food security in the country. For instance, by restricting movement, food production was reduced which negatively affected the amount of food stored, distributed, and sold. Therefore, based on this finding, it is evident that strategies employed in containing the Ebola virus spread have negative nutrition-related impacts. 

The information gathered in the research is important as it is applicable in informing the coping strategies when there are nutrition challenges in cases of epidemics and with restricted movements. One of the limitations that faced the study is that the key informants who were working in Sierra Leone during the Ebola virus epidemic were no longer working in those positions, thus they could not take part in the interview process, requiring the researchers to involve their key successors to the positions (Kodish et al., 2019). The interesting part of the study is that it has employed simple language and approaches in the process of study, thus making it easily understandable. 

Factors Contributing to Ebola Virus 

There are a high case fatality and infectivity rate associated with the Ebola disease. For instance, in the 2014 epidemic, the fatality rate was established to be 70%, in which the state continued declining when treatment centers were established (Adongo et al., 2016). Despite, the Ebola virus being highly infectious, adoption of measures such as the application of hand sanitizers, washing hands with water and soap as well as avoiding any contact with the infected individuals' body fluids the condition can be contained (Singh et al., 2017). According to Adongo et al. (2016), family members, as well as healthcare workers, are at the highest risk of contracting the disease directly during the process of taking care of the patients. Some cultural practices act as a hindrance in the prevention efforts of the spread of the Ebola virus (Wendelboe et al., 2018). For instance, sociocultural practices act as potential hindrances in the timely identification of the Ebola cases and adoption of approaches to contain the situation. 

Some sociocultural practices that risk most of the communities include washing and handling of a corpse as well as mass attendance of burials during the Ebola outbreaks. Additionally, overemphasis on family ties leads people to physically handling contaminated clothes that increase their risk of infection. Mass funeral attendance and burial ceremonies increase other people’s risk of contracting the disease, hence the need to communicate risks associated with certain cultural practices as a way of containing the disease. 

Annotated Bibliography 

Adongo, P. et al. (2016). Preparing towards Preventing and Containing an Ebola Virus Disease Outbreak: What Socio-cultural Practices May Affect Containment Effort in Ghana. Neglected Tropical Diseases, 10(7). 

The source describes how the Ebola Virus disease has a high fatality rate. The authors emphasize on precautionary measures to minimize the spread of the disease. The authors also highlight factors that are responsible for the high rates of infections in certain areas. As a source of information for the current study, the authors discuss socio-cultural practices that put family members at a high risk of the infection including performing certain burial rituals. 

Beeching, N. et al. (2014). Ebola Virus Disease. The BMJ Journal, 349(7348). 

The work looks at how transmission of Ebola virus occurs between humans. The author explain the incubation period following an infection as 5-9 days, while in 95% of the patients, the range is 1-21. The source also indicates that symptoms of the Ebola virus are nonspecific in the early days, which makes the diagnosis process hard. The source is significant in the current research as it provides significant information about the incubation period of the disease, while providing facts on the reasons why diagnosing the virus is hard in the initial stages of the condition. 

Burd, E. (2015). Ebola Virus: A Clear and Present Danger. Journal of Clinical Microbiology, 53(1), 4-8. 

The author describes Ebola virus epidemic that occurred in Western Africa, in countries such as Sierra Leone, Liberia and Guinea. The author indicates that the immense spread of Ebola virus is associated with poor sanitation, insufficient medical facilities, and unsafe burial practices. The source is significant in the current research as it highlights the important cultural factors that are responsible for the continued spread of Ebola virus in different parts of the world. 

Goeijenbier, M. et al. (2014). Ebola Virus Disease: A Review on Epidemiology, Symptoms, Treatment, and Pathogenesis. The Netherlands Journal of Medicine, 72(9), 442-448. 

Goeijenbier et al. explains about the largest outbreak that occurred in West Africa. The authors describe Zaire Ebola Virus in detail which is responsible for the outbreak ascertaining that the disease had a case fatality rate of more than 40%. This study is important in the current research as it provides detailed information concerning Zaire Ebola Virus, its genus and family, thus helping to understand detailed information concerning the clinical manifestations of the disease. 

Hoenen, T. et al. (2019). Therapeutic Strategies to Target The Ebola Virus Life Cycle. Nature Reviews Microbiology. 17(1), 593-606. 

The source discusses Ebola virus life cycle. It explains about the importance of high level screening technologies in identifying the host, viral factors and all the other factors that come into play during an infection to act as the target during the intervention processes. Hoenen et al. study is crucial in this current study as it provides detailed information about the Ebola virus life cycle, thus providing significant information about the processes that occur at every stage that can act as an intervention target. 

Kimura, H. et al. (2015). Ebola Virus Disease: a Literature Review. Journal of Coastal Life Medicine, 3(2), 85-90. 

The source presents Ebola virus’s different disease symptoms that range from vomiting, headache, muscle aches and diarrhea. The authors indicate that in the advanced cases of the disease, a patient may have unexplained bleeding in the gums, nose and eyes. The source also explain that in most cases of the Ebola virus disease, it starts by portraying symptoms similar to those shown by an individual with influenza. Thus, the study is necessary in understanding about the complexity of diagnosing the disease at the initial stages of treatment. 

Kodish, S. et al. (2019). A Qualitative Study to Understand how Ebola Virus Disease Affected Nutrition in Sierra Leone-A Food Value Chain Framework for Improving Future Response Strategies. Neglected Tropical Diseases Journal, 13(9). 

Kodish et al. sought to investigate how the 2014-2016 Ebola virus outbreak, affected the nutrition sector in Sierra Leone. The authors identify that the virus in itself is capable of minimizing the commitment of people in food production. Additionally, they explain that strategies to minimize the spread of the disease limit movement and direct production of foods that negatively affect the food value chain. Kodish et al. research is important in the current study as it identifies various strategies employed in the containment process of Ebola virus and their negative effects on nutrition and other aspects of life. 

Muñoz-Fontela, C. & McElroy, A. (2017). Ebola Virus Disease in Humans: Pathophysiology and Immunity. In: Mühlberger E., Hensley L., Towner J. (eds) Marburg- and Ebolaviruses. Current Topics in Microbiology and Immunology , Springer, Cham. https://doi.org/10.1007/82_2017_11 

The source discusses the historical progress of Ebola virus since its discovery in1976. The authors indicate that the virus has been causing human disease outbreaks of varying magnitude, in which their adverse effects include collapsing the healthcare systems of certain countries. In the current research, the source will help identify the factors that are associated with the differences in magnitude of disease outbreak in a country, such as economic factors. 

Pacheco, D. et al. (2015). Ebola Virus- From Neglected Threat to Global Emergency State. Article Review, 62(5), 458-467. 

The source identifies that bats are the natural reservoirs of the Ebola virus. The authors also explain that diagnosing Ebola virus is difficult because of the initial symptoms of the condition, which try to mimic other conditions. The authors also explain that limitations in the treatment of Ebola virus are associated with the disinterest of government authorities in solving the issue. This source is important in the current research as it identifies symptoms that people with Ebola virus portray. It also provides important information about how the Ebola virus remains in a state of emergency due to the lack of coordination between international communities. 

Rajak, H. et al. (2015). Ebola Virus Disease: Past, Present, and Future. Asian Pacific Journal of Tropical Biomedicine, 3(3), 337-343. 

The source identifies Ebola virus disease as a deadly ailment, due to the high mortality rate associated with the condition. The authors also include the history of Ebola virus in which they indicate that the condition was first discovered in 1976 in Zaire. Therefore, the study is crucial in the current study as it provides the history of the Ebola disease, and the development and discoveries that have been made concerning the disease since then. 

Singh, R. et al. (2017). Ebola Virus-Epidemiology, Diagnosis, and Control: Threat to Humans, Lessons Learnt and Preparedness Plans- an Update on Its 40 Year’s Journey. Review Article, 37(1), 98-135. 

The source discusses the characteristics of Ebola virus, in which it also ascertains the disease to be highly harmful to man. The authors also indicate that currently, Ebola virus is an international health problem, especially because of the easy transmission of the disease between individuals. The source is crucial in the current research as it identifies the reservoir host of the Ebola virus as bats, and the ease of transmitting the disease. It also provides significant information about the importance of timely diagnosis for effective results from the disease. 

Sukul, A. et al. (2016). Ebola Virus Pathogenesis: Implications for Diagnosis and Prevention. International Journal of Pharmacology and Toxicology, 6(2), 74-81. 

The authors analyze Ebola virus and the way it spreads between living organisms. The authors ascertain that Ebola virus is transmitted between humans through contaminated body fluids. The study also includes the common symptoms that are exhibited by an individual with the Ebola virus disease, which include nausea, cramping and abdominal pain. Sukul et al. study is important in the current research as it notes the signs and symptoms of an individual with Ebola virus. Additionally, it provides significant information about complications that originate from Ebola virus disease. 

Wambani, R. et al. (2015). Ebola Virus Disease: A Biological and Epidemiological Perspective of a Virulent Virus. Journal of Infectious Diseases and Diagnosis, 1(1), 1-6. 

The source discusses the various factors that are responsible for the frequent epidemics in Sub-Saharan Africa due to Ebola virus. The authors indicate that there is a knowledge gap in the mitigation strategies because of the easy transmission of the virus between humans. The study is important in the current research as it explains why Ebola virus remains a high risk disease in Sub-Saharan African and the need for collaboration between departments to mitigate the current risky situation. 

Wendelboe, A. et al. (2018). Managing Emerging Transnational Public Health Security Threats: Lessons Learned from the 2014 West African Ebola Outbreak. Globalization and Health, 14(75). 

The work evaluated the 2014 West African Ebola outbreak to identify the characteristics that greatly risked the nation. The authors also indicate the lessons learnt from the research, which would inform public health security in developing techniques to curb all the threats from the disease. The article is appropriate for the current research study as it provides information of the positive correlation between poor infrastructure and high risk of the infection. Therefore, the research informs approaches that the public should look out for to minimize the spread of the Ebola virus disease. 

Yu, D. et al. (2017). The Lifecycle of the Ebola Virus in Host Cells. Oncotarget, 8(33), 1-10. 

The authors describe the Ebola virus lifecycle in a human or non-human’s primates cells. The source explain that the mechanisms involved in the lifecycle remain unclear, hence emphasizing the need for urgent study into the matter. The study is vital in the current research as it describes the Ebola virus’ lifecycle pinpointing the various processes occurring at the entry, uncoating and fusion, transcription and replication as well as the assembly and budding stage of the virus’ lifecycle. 

References 

Adongo, P. et al. (2016). Preparing towards Preventing and Containing an Ebola Virus Disease Outbreak: What Socio-cultural Practices May Affect Containment Effort in Ghana. Neglected Tropical Diseases, 10(7). 

Beeching, N. (2014). Ebola Virus Disease. The BMJ Journal, 349(7348). 

Burd, E. (2015). Ebola Virus: A Clear and Present Danger. Journal of Clinical Microbiology, 53(1), 4-8. 

Goeijenbier, M. et al. (2014). Ebola Virus Disease: A Review on Epidemiology, Symptoms, Treatment, and Pathogenesis. The Netherlands Journal of Medicine, 72(9), 442-448. 

Hoenen, T. et al. (2019). Therapeutic Strategies to Target The Ebola Virus Life Cycle. Nature Reviews Microbiology. 17(1), 593-606. 

Kimura, H. et al. (2015). Ebola Virus Disease: a Literature Review. Journal of Coastal Life Medicine, 3(2), 85-90. 

Kodish, S. et al. (2019). A Qualitative Study to Understand how Ebola Virus Disease Affected Nutrition in Sierra Leone-A Food Value Chain Framework for Improving Future Response Strategies. Neglected Tropical Diseases Journal, 13(9). 

Muñoz-Fontela, C. & McElroy, A. (2017). Ebola Virus Disease in Humans: Pathophysiology and Immunity. In: Mühlberger E., Hensley L., Towner J. (eds) Marburg- and Ebolaviruses. Current Topics in Microbiology and Immunology , Springer, Cham. https://doi.org/10.1007/82_2017_11 

Pacheco, D. et al. (2015). Ebola Virus- From Neglected Threat to Global Emergency State. Article Review, 62(5), 458-467. 

Rajak, H. et al. (2015). Ebola Virus Disease: Past, Present, and Future. Asian Pacific Journal of Tropical Biomedicine, 3(3), 337-343. 

Singh, R. et al. (2017). Ebola Virus-Epidemiology, Diagnosis, and Control: Threat to Humans, Lessons Learnt and Preparedness Plans- an Update on Its 40 Year’s Journey. Review Article, 37(1), 98-135. 

Sukul, A. et al. (2016). Ebola Virus Pathogenesis: Implications for Diagnosis and Prevention. International Journal of Pharmacology and Toxicology, 6(2), 74-81. 

Wambani, R. et al. (2015). Ebola Virus Disease: A Biological and Epidemiological Perspective of a Virulent Virus. Journal of Infectious Diseases and Diagnosis, 1(1), 1-6. 

Wendelboe, A. et al. (2018). Managing Emerging Transnational Public Health Security Threats: Lessons Learned from the 2014 West African Ebola Outbreak. Globalization and Health, 14(75). 

Yu, D. et al. (2017). The Lifecycle of the Ebola Virus in Host Cells. Oncotarget, 8(33), 1-10. 

Glossary 

Coagulation- It is the process by which one stops excessive bleeding through formation of blood clots. 

Coagulopathy- Refers to a condition in which the blood’s ability to form clots is affected thus resulting to excessive bleeding. 

Dysphagia- Is a term that refers to swallowing difficulties. 

Myalgia- It is a medical term that refers to muscle pain and aches.