Abstract
The 2014-2015 Ebola virus disease (EVD) epidemic in West Africa was very momentous for the public health, healthcare systems, and economic equilibrium. Ebola is transmitted through contact with animals and their body fluids, which leads to immune dysfunction, organ failure, and bleeding manifestations. Diagnostic means such as serological assays and molecular tests will speed up the early diagnosis and treatment beginning. Despite the fact that supportive care remains the basis of treatment, the development of experimental therapies and vaccination programs provide important areas in which to intervene. Notwithstanding, the problems are still present, especially in the resource-poor areas. The pandemic exposed the shortcomings in healthcare systems, which were aggravated by cultural factors and unstable politics, leading to general distrust and healthcare avoidance. Disruption of the healthcare services exacerbated the situation and contributed to increased deaths from other illnesses. Combating these issues necessitates encompassing plans that include better infrastructure, community communication, and international partnerships for preventing future epidemics and mitigating their impact.
Etiology and Mechanisms of Disease
The source of Ebola virus disease (EVD) involves the passing of the Ebola virus to human beings via contact with infected animals, most notably bats or non-human primates, and through direct contact with the body fluids of the infected individuals (Baseler et al., 2017). Although the initial transmission has its target cells to dendritic cells and monocyte/macrophage lineage cells, it leads to systematic spread to lymphatic vessels and the bloodstream via the pathway. The exact wild reservoirs of the virus and the immunological mechanisms of initial jumps are among epidemiologists’ currently interesting points to research (Baseler et al., 2017).
The EVD pathogenesis mechanisms are complex and diverse. The virus adopts several tactics in order to evade the immune response of the host through processes like inhibition of interferon one and variation of dendritic cell maturation. It facilitates viral dissemination and invasion into virtually every cell by replicating unabatedly, consequently causing tissue impairment and organ function impairment. Immunologic dysregulation leads to both hypofunction and hyperproliferation, which results in disease progression. Also, the virus itself disrupts normal functions of cells like these infected hepatocytes and endothelial cells by lysing them, which in turn leads to tissue death, vascular leakage, and coagulopathy (Baseler et al., 2017). These three mechanisms are the basics of the classical tales about Ebola, including hemorrhage, multiorgan failure, and very high mortality.
Signs and Symptoms
The signs and symptoms of Ebola virus disease (EVD) include fever (>38°C), weakness, fatigue, muscle weakness, myalgia, and gastrointestinal symptoms such as profuse watery frequency of diarrhea and vomiting. Patients may also experience abdominal pains, difficulty in swallowing, and oral ulcers. As the disease progresses, the patients might develop problems with the central nervous system like meningoencephalitis, peripheral neuropathy, seizures, and even coma. In addition to hypoxia and respiratory failure, there can be cardiac anomalies like myocarditis. Optical disturbances, rash, pancreatitis, and thyroid abnormalities are other symptoms. The photo indicates the importance of knowing the signs and symptoms for early detection, diagnosis, and treatment of EVD, which prevents further transmission and guarantees improved patient outcomes.
Diagnostic Methods
Ebola diagnostic methods have gone through a continuous evolution, with different techniques being used for the detection of the virus. Serological assays have played a central role in the past by identifying host antibodies against the virus; however, during the acute phase, they may lack utility due to their variability in the onset and lower sensitivity. On the other hand, antigen tests, such as ELISA, find viral proteins in patient samples directly, so they are very good for acute cases while detecting (Broadhurst et al., 2016). Such diagnostic tests take advantage of the early accumulation of the viral proteins in the blood, allowing for rapid diagnosis and treatment measures to be implemented accordingly.
Molecular tests, in particular real-time RT PCR, feature as another crucial diagnostic technique for Ebola viral infection. Through identifying viral RNA in patient samples, these assays provide high sensitivity and specificity, which enables early and accurate diagnosis of the disease even before viral antigens can be detected. While facing transportation and logistical difficulties in resource-limited areas, these diagnostic methods in temporary laboratories play a key role in outbreak response, which leads to quicker diagnosis and patient management, as well as contact tracing (Broadhurst et al., 2016).
Another diagnostic tool used for Ebola virus detection is the random primers amplified isothermal amplification (LAMP), which delivers a fast and precise detection of RNA viral thousands at constant temperatures without requiring extra expertise in equipment. LAMP platforms showed potential applications for use in resource-limited settings because of their simplicity and suitability for “on-the-go” analysis. Furthermore, the technological advance marked by nanoscope sequencing has contributed much to the in-site real-time genomic analysis of the Ebola virus using samples directly in the field. Therefore, sequencing genomes leads to the comprehension of viral genetic adaptations, virus transmission manners, and drug resistance more quickly than traditional methods do (Broadhurst et al., 2016). These advanced diagnostic techniques, as a supplement to the existing methodologies, bring timely and efficient detection and reaction to the Ebola outbreaks. Not only is continuous research and development in this area salient, but it is also crucial for being one step ahead of the virus, thus enhancing the effectiveness of outbreak control measures.
Pathology of the disease
The Ebola virus infection is characterized by pathologic changes in the body on multiple organ systems. Upon infection, the virus attacks immune cells such as macrophages and dendritic cells, which leads to immune dysregulation and cytokine storm. Consequently, widespread inflammation, vascular damage, and coagulation defects arise, resulting in hemorrhagic manifestations (Menicucci & Ilhem Messaoudi, 2015). The virus is also capable of damaging endothelial cells, which in turn results in vascular leakage and multiorgan failure. In severe cases, the patients may develop disseminated intravascular coagulation, shock, and organ failure, mostly affecting the liver, kidneys, and central nervous systems. Moreover, the virus can cause gastrointestinal symptoms like diarrhea and vomiting, which can make dehydration and electrolyte imbalance situations worse (Baseler et al., 2017).
Prognosis and Treatments of the Disease
The prognosis for Ebola virus disease (EVD) will depend on the health of the patient, age, and the specific strain of the virus. The mortality rate usually ranges from 25% to 90%, demonstrating how some outbreaks had higher death rates. Those patients who overcome the acute phase of the disease may suffer health effects in the longer term, such as joint pain, swollen joints, blurred vision, and neurological problems (Fedson & Rordam, 2015). While EVD is a life-threatening condition, it is supportive care that remains the main focus of the treatment. Among them are fluid and electrolyte balance preservation, adequate oxygenation, hemostasis, and hypovolemic shock management (Menicucci & Ilhem Messaoudi, 2015). Experimental methods with various outcomes, like antiviral drugs and monoclonal antibodies, show some positive results in early clinical trials. However, their efficacy still needs more research. Vaccination programs have been developed and used in outbreak settings as well to stop transmission, though limited vaccine availability in resource-poor areas still remains a problem (Baseler et al., 2017). Early detection, case identification, and follow-up of contacts are vital for containing and preventing the spread of the virus among the population.
The majority of Ebola virus disease (EVD) cases recover within weeks. However, a proportion of people go into a chronic phase with symptoms that persist for several months to years beyond acute infection. Common problems often include joint pain, muscle weakness, exhaustion, eye problems, and neurological complications such as memory loss. The exact mechanisms of the chronic stage remain unclear. It could be the result of continuous viral replication coupled with immune dysregulation and tissue damage. Ebola virus can remain in bodily fluids even after recovery, which could cause the symptoms and the level of risk of transmission (Fedson & Rordam, 2015). The inflammatory reactions in acute infection may also result in damage to the organs; therefore, long-term health is also impacted. Research is going on to understand the logistics of this phase and the formation of management strategies.
Public Health Impact
The effect of the 2014-2015 Ebola outbreak in West Africa on public health was extensive, coupled with the individual, family, and country scales. Being the front liners in the fight, the healthcare workers were at intense risk of catching the virus or dying due to inadequate gear and health facilities (Delamou et al., 2017). The mistrust of the communities with health systems makes them unused to certain medical services and end up avoiding the health facilities. The quick spread and prolonged persistence of this outbreak were assisted by poor health systems, cultural factors, poverty, and instability in the political sphere in Guinea, Liberia, and Sierra Leone (Delamou et al., 2017). Poorly executed control strategies and lack of interaction contributed to the destabilization of faith, which hampered the successful implementation of response efforts. Interruption of regularly planned healthcare services led to increased mortality rates from other diseases, and hence, the situation of the patients continued to worsen.
References
Baseler, L., Chertow, D. S., Johnson, K. M., Feldmann, H., & Morens, D. M. (2017). The Pathogenesis of Ebola Virus Disease. Annual Review of Pathology: Mechanisms of Disease, 12(1), 387–418. https://doi.org/10.1146/annurev-pathol-052016-100506
Broadhurst, M. J., Brooks, T. J. G., & Pollock, N. R. (2016). Diagnosis of Ebola Virus Disease: Past, Present, and Future. Clinical Microbiology Reviews, 29(4), 773–793. https://doi.org/10.1128/cmr.00003-16
Delamou, A., Delvaux, T., El Ayadi, A. M., Beavogui, A. H., Okumura, J., Van Damme, W., & De Brouwere, V. (2017). Public health impact of the 2014–2015 Ebola outbreak in West Africa: seizing opportunities for the future. BMJ Global Health, 2(2), e000202. https://doi.org/10.1136/bmjgh-2016-000202
Fedson, D. S., & Rordam, O. M. (2015). Treating Ebola patients: a “bottom up” approach using generic statins and angiotensin receptor blockers. International Journal of Infectious Diseases, 36, 80–84. https://doi.org/10.1016/j.ijid.2015.04.019
Menicucci, A. R., & Ilhem Messaoudi. (2015, May 8). Pathophysiology of Ebola Virus Infection: Current Challenges and Future Hopes. ResearchGate; American Chemical Society. https://www.researchgate.net/publication/276531953_Pathophysiology_of_Ebola_Virus_Infection_Current_Challenges_and_Future_Hopes
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