Ebola Virus Disease - Essay Example

Ebola Virus Disease (EVD) Introduction Ebola Virus Disease (EVD) is a sophisticated, deadly and rare viral illness that causes fearsome clinical symptoms and manifestations that are worth understanding. The disease is transmitted from animals to human beings and spread through human-to-human transmission to persons. How, the average case fatality rate for the EVD is 50% though their rates has been shifting from 25% to around 90% for the past outbreaks as evidenced in the West Africa according to CDC (2014). EVD epidemics as reported by the National Notifiable Disease Surveillance System (NNDSS) and other agencies such as the Red Cross had been significant been occurring in a remote area near tropical rainforests in Central Africa. Nevertheless, the recent outbreaks have involved major towns and rural areas mostly in various parts of West Africa according to CDC (2014). Conversely, the EVD background can be traced back in the 1976 simultaneously in Sudan and Democratic Republic of Congo (DRC) as an acute and fatal illness if untreated. However, the countries that have been severely affected are those with weak health systems and inadequate human and infrastructural resources according to Feldmann & Feldmann (2013). However, since the Ebola Virus Disease transmission, symptoms and prevention and control is of international public health emergency concern according to the World Health Organization (WHO) community engagement and early supportive care are the most central points of controlling the Ebola outbreaks. It is worth understanding that, no licensed Ebola vaccines have been recently been registered, but potential clinical candidates are undergoing examination and evaluation (Filippone, 2013). Analysis presented in this paper is helpful in understanding the background, the causative agent of classification, structure, replication, as well as transmission. The paper uncovers the epidemiological statistics of Ebola virus diseases in relation to the clinical manifestation, preference and the laboratory strategies used in the disease identification according to Roddy et al. (2012). Similarly, the paper demonstrate realistically the preventive and treatment measures are exploiting the past, current and the future outlook of the Ebola Virus Disease. Lastly a conclusion and recommendation is given illustrating various adaptive mechanisms that can be done to in the epidemic-prone area to be successful prepared in handling the EVD and communication before it can widely spread (Lister, 2014). Ebola Virus classification and structure Ebola virus as the causative agent for the Ebola Virus Disease belongs to the filovirus family based on its genetic structure. The virus is classified into five species based on the origin namely Zaire ebolavirus (ZEBOV), Sudan ebolavirus (SEBOV), Bundibugyo ebolavirus (BEBOV) and Tai Forest ebolavirus (REBOV). ZEBOV is the most virulent strain with the highest lethality rate. Ebola virus is filamentous and elongated virus with uniform diameter (20-30nm) ranging between 800-1000nm in length and 14000nm long (Greger, 2007). The viral pleomorphic fragments take multiple distinct shapes such as 6-shaped, u-shape and circle-shaped contained in a lipid membrane. The Ebola virus genome is a non-segment and single-stranded about 19kb long (Filippone, 2013). The Ebola virus genome contains seven open reading fragments of encoding structural proteins which constitute virion envelope glycoprotein (GP), viral polymerase, matrix proteins VP40 and VP24, nonstructural proteins VP30 and VP35 and well as nucleoproteins (NP). Ebola Virus Replication The Ebola causative agent enters the host target cells through endocytosis process, and replication occurs in the host cells cytoplasm. Upon replication, the Ebola virus form soluble 60kDa proteins that are bind on the viral membrane through transcriptional editing with both biochemical and biological properties. The replicated viral genome form positive-strand antigenomes as well as full-length genome that in turn is transcribed into negative-stranded virus progeny that accumulate near the cell membrane. Upon infection, the causative agent affects the hosts immune and blood coagulative defense systems resulting in severe immune suppression according to CDC (2014). Ebola Virus Disease Transmission A clear natural Ebola Virus host is unknown; however, fruit bats of Pteropodidae family are thought to be the Ebola Virus natural hosts. Ebola virus is introduced through close contact with the infected animal body fluids, secretions and blood found in the rainforests into the human population. In human population, the Ebola Virus disease is spread through human-to-human contact mechanism via direct contact with the surfaces and materials contaminated with infected fluids (Greger, 2007). Health workers in close contact with the infected patients can spread the Ebola virus disease where strict infection control precautions are not practiced as well as infect themselves. Burial ceremonies in close touch with the body of the deceased can also play a part in transmitting the Ebola virus disease. However, infected individuals remain infectious as long as their body fluids and blood contains the Ebola virus (Gatherer, 2014). For instance, men or women who have recovered from the Ebola Virus Diseases can still transmit the disease through their semen or virginal fluids up to an average of 7 weeks of their recovery from the illness. Ebola virus epidemiology and statistical findings The Ebola virus (filoviruses) were first identified in 1967 among the Marburg Germany vaccine workers in Uganda who came into direct contact with animals during preparation of primary cell cultures for polio vaccines designing the virus to be Marburg virus. In 1976, other genus of Ebola virus was recognized in Sudan and Zaire causing several cases in the Sub-Sahara Africa. In 1995 cases, were reported in Kikwit, DRC and Sudan infecting more than 400 cases (Majumder, 2014). However, recent outbreaks have been reported from 2014-2015 in West Africa urban and rural cases as well as infecting the health workers exposed to infected patients in West African and the United States. The case fatality ratio range from 41%-90% in the epidemic area, latent and infectious period based on Bayesian model-based estimates is 9.4 and 5.7 days respectively. Incubation period is 2-21 days while the minimum and maximum serial interval is 7 and 17 days respectively (Organization, 2014). Clinical symptoms EVD incubation period is 2 to 21 days with an infectious dose of 1-10 organisms in nonhuman primates by aerosol transmission. However, human beings are not contagious of the Ebola virus until they develop clinical symptoms. Sudden onset of fever, headache, muscle pain, and fatigue are the first’s symptoms of the Ebola virus disease followed by diarrhea, vomiting, rashes and symptoms of impair liver and kidney function. In addition, internal and external bleeding can be seen among others. Laboratory findings for Ebola Virus clinical symptoms include low platelets and white blood cell count as well as elevated liver enzymes (Bornholdt za & Saphire’2013). Laboratory strategies used in Ebola virus identification and diagnosis Virus isolation and identification method are a sensitive, simple and fundamental method for the diagnosis of MHF and EHF. However, MARV and EBOV are known to exhibit a well growth in a variety of cell lines in conjunction with the Vero E6 cells and the Vero cells. Nevertheless, the virus isolation method alone does not yield an etiological diagnosis. Therefore, monoclonal antibodies for the serological identification of the EBOV and the NPs for MARV isolate (Gatherer, 2014). Molecular diagnostic method (RT-PCR) method for EHT and MHF is used in epidemic areas in conjunction with the DNA-intercalating dye SYBR green I and Filo-B for amplification of the L genes of the Ebola virus. In relation to the MHF and the EHF Molecular diagnosis, molecular diagnostic methods have been proven to possess specific, sensitive and efficacious properties in the diagnosis of Ebola virus infections. Therefore, molecular techniques are useful in determining the sensitivity as well as the specificity of the virology diagnosis in terms of false-positive or false-negative results (Funk & Kumar, 2015). Immunofluorescence techniques serve as an alternative method for identifying and detecting specific Ebola virus antibodies. The method applies the EBOV rNP-expressing HeLa cells as a highly sensitive and concrete antigen that reacts with the human monoclonal Fab fragment antibodies determining the presence of the EBOV virus. Cell culture techniques in Ebola diagnosis detect the viral RNA and genome proteins by the PCR and ELISA methods in the earlier stages of the disease progress in the human being and human remains. However, cell culture techniques are feasible during the periods of outbreaks in epidemic areas (Lister, 2014). Electron microscopy is helpful in identification of distinctive shapes of the Ebola virus (unique filamentous forms) which helps in the study of the internal structure, although the method cannot be used in differential diagnosis of various Ebola virus strains (Roddy, 2012). Conversely, other emerging technologies in diagnostic virology for Ebola virus such as nonspecific laboratory testing (ALT, AST and DIC) has been applied alongside specific laboratory tests to aid in differential diagnosis and identification of Ebola virus. Ebola Virus Disease Prevention Strategies Application of multiple concurrent transmission preventing strategies should be put in place to avoid the spread of the Ebola virus. Therefore, employment of strict infection control measures in conjunction with the implementation of personal protective equipment is the essential components of preventing the virus transmission in healthcare setting (Lister, 2014). The virus prevention strategies that should be used in eradication, control and prevention of Ebola virus transmission includes; infection control precaution procedures, environmental infection control strategies, monitoring and travel restriction policies and precautions during convalescent period. Infection control strategies provide a detailed review of the Ebola virus infection control measures in handling infected and suspected patients with the Ebola virus. The infection control strategies provide recommendation of isolating hospitalized patients suspected or known infected with the Ebola virus, appropriate use of correct personal protective devices, proper hand hygiene and correct use of contact and droplet precaution standards. However, Infection control strategy can be achieved through training health care workers and engaging the community in the infection control (Muyembe-Tamfum & Paweska, 2012). Monitoring and traveling restrictions can be applied through close monitoring of the movement of individuals suspected or treated with the Ebola virus as well as conducting a travel and transport risk assessment in order to prevent the spread of the disease. In addition, breastfeeding and infant care strategy by monitoring infected mothers not to spread the virus into their infants through breastfeeding. Precautions during the convalescent period approach can be applied in protecting secondary transmission of the patients recovering from the Ebola even if the Ebola virus may not be detectable in their blood (Organization, 2014). However, although there are no approved vaccines, ‘’single-shot’’ vaccines (adenovirus vaccination be used to provoke rapid immune response that in turn aid in spread control of the Ebola virus. Public health response strategies can be initiated in providing effective communication with the government authorities, health professions, and the community. In addition, the public health sector can provide health education and supportive care that provides long-standing practices that control the spread of the Ebola virus (CDC, 2014). Ebola Virus Treatment strategies Treatment strategies Prevention Strategies Strict infection control measures Supportive care Proper hand hygiene antibacterial and antiviral therapies Contact and droplet precaution standards respiratory support Ebola treatment strategies include; approach to therapy, supportive care, fluid, and electrolyte replacement, respiratory support, and antibacterial or antiviral therapies. In a broad point of view, the approach to therapy Ebola virus treatment strategy involves how the health workers maintain uncontaminated treatment activities for the care of infected patients (Goeijenbier & Van Gorp, 2014). Supportive care to an Ebola infected patient are designed to prevented the infected patient from further complication such as treating severe hypovolemia, correcting electrolyte imbalance caused by diarrhea and vomiting as well as preventing intravascular depletion of the Ebola infected patient. Addition supportive treatment measure for the Ebola infected patients includes respiratory support, symptomatic management of Ebola Virus Disease symptoms such as the use of anti-diarrhea and renal replacement therapy. Antimicrobial therapy can be applied in the treatment of the Ebola Virus Disease for severely ill patients for treatment of other possible or concomitant infections such as bacterial sepsis. Antiviral therapy can be initiated for the treatment of Ebola Virus by the use of repurposed drugs such as favipiravir and brincidofovir antiviral agents even though there is no approved medication for the disease treatment (Funk & Kumar, 2015). In this regard, favipiravir and brincidofovir antiviral analogs inhibits the replication of the Ebola virus preventing the disease progression as tested in Japan and found to be safe in Phase II and III clinical trials. Ebola virus disease future outlook The future Ebola outlook is learning from the past large-scale outbreaks in order to prevent the future outbreaks. Though the battle is currently in West Africa, health organization, and other support groups can work with those affected regions to create means and opportunities of controlling the disease outbreak in those regions (Gatherer, 2014). Massive campaigns through Ebola eradication, control and treatment can be done to create community awareness of the Ebola virus transmission, causative agents and management through heath education and advocacy. In addition, countries should be working together in building Ebola Virus Disease surveillance and monitoring system that will help in determining the best treatment and vaccination for the Ebola virus. However, WHO should support risks countries in developing Ebola preparedness plans and crisis communication according to CDC (2014). Conclusion Ebola Virus disease is complicated and fatal disease that can only be understood through collective bargains. Understanding the background of the Ebola virus infection from the causative agent characteristics, transmission, laboratory identification and diagnosis of treatment and prevention serves as a turning point in the disease management and control. However, community engagement, contact tracing, logistical support for the susceptible and infected patients in risk areas and assistant training add value in the past, present and the future outlook of the disease prevention and control. 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