Ebola: Causes, Symptoms and Treatment

Table of Contents

1.1 Introduction on Ebola virus.

1.2 History of Ebola.

1.3 Characteristics of Ebola virus.

1.4 Symptoms of Ebola.

1.5 Diagnosing Ebola.

1.6 Treatment methods for Ebola.

1.7 Conclusion.

1.1 Introduction on Ebola virus.

Ebola is an emerging virus even though it is not new-as it has been emerged before and can be classified as one of the most ancient viruses found and it is once again appearing (Draper, 2002). Ebola was first identified in the Democratic republic of Congo or which was previously known as Zaire, since it appeared in the town of Yambuku-central Africa in the year 1976 (Draper, 2002).The largest and the most complex Ebola outbreak since the first outbreak was in 1976, which was experienced by the people of west Africa in march 2014 (World Health Organization, 2014). This particular outbreak has gone through many cases which have lead to death more than all the previous outbreaks combined (WHO, 2014). Ebola can be classified according to its genetic antigenic characterization (Porrut, 2005).

1.2 History of Ebola.

Ebola virus was first discovered and experienced in the form of two simultaneous outbreaks, first due to the E.Sudan and the other due to E.Zaire, both these outbreaks happened in places close by, in Sudan near the border with the Democratic republic of Congo (Smith, 2005).This virus further affected the towns of Nzara and Maridi between June and November 1976 which gave mortality rate as 53%: 150 of 284 victims which is the characteristic of the Sudan subtype (Smith, 2005).

The second outbreak was due to the E.Zaire which occurred in the border of the democratic republic of Congo which is close to Sudan and the Central African Republic between August and November in the same year 1976 (Johnson, 2005). The virus is named after the Ebola River where the virus was first discovered in 1976 (CNN, 2014). The third outbreak occurred between July and October 1979 in the same place attacked by the Sudan virus, but didn’t cause great extensive outbreaks like the first two, this virus affected 34 people and killing 22- mortality 65% (Porrut, 2005).

1.3 Characteristics of Ebola virus.

Among the Filoviridae virus, the two commonly found deadly viruses are the Ebola and the Marburg viruses- This viral family contains viruses with non segmented negative-sense RNA genomes (Geisbert and Jahrling, 2005,). Ebola virus is not harmful unless it fuses its glycoprotein viral with the host cell membrane (Wood-Lewis et al., 2005). There are mainly five types of Ebola viruses identified, which are: Ebola Zaire, Ebola Ivory Coast, Ebola Sudan, Ebola Bundibugyo, Ebola Reston and the one which is producing the outbreaks in 2014 was due to the Zaire species (WHO, 2014) Filovirus cell entry is supported by its class I fusion protein or the spike protein GP_{1, 2} (Volchkov, et al., 2011). There are seven genes in the order 3’ leader, nucleoprotein, virion-protein 35, VP40, glycoprotein, VP30, VP24, RNA-dependent RNA polymerase (L)-5’ trailer found in the genome (Sanchez et al., 2011).

Ebola virus is transmitted to a human via having direct contact with another Ebola victim-here the direct contact includes: blood, secretions, organs or other body fluids of the victim and also the surfaces and materials which are contaminated with these fluids (WHO, 2011). Usually the victims of Ebola are infectious as long as their blood and body fluid-which includes semen and breast milk is contaminated with the virus (WHO, 2011). Ebola releases number of countless chemicals like cytokines, chemokines and histamines when it infects different types of cells (Smith, 2009).this causes the number of symptoms we can observe to conclude whether the person is a victim of Ebola or not( Smith, 2009).this virus’s genome is particularly small and appears as a long worm l where it resembles a length of thread but it can also be in a U-shaped or in a shape of “6” or even at times circular.( Smith, 2009).

1.4 Symptoms of Ebola.

Ebola viruses are pathogenic for humans, as they cause specific febrile hemorrhagic disease and these symptoms will be directly shown after nearly a week (Baron, 2005) usually the symptom of Ebola includes fever, headache, and abdominal pain. Nausea, fatigue and mostly an ill feeling, but this is what makes diagnosing Ebola difficult, as these symptoms are common for many diseases (Smith, 2009). But to elaborate more, first symptoms of Ebola are sudden fever, muscle pain followed by headache and sore throat along with this the rest of the symptoms are shown which are: vomiting, diarrhea, rash and even at times internal and external bleeding is shown (WHO, 2014).

1.5 Diagnosing Ebola.

It is usually difficult to categorize the Ebola virus and Marburg virus as they both have got similar clinical symptoms; here the most common symptoms are severe, febrile and acute fever (Feldman et al, 2005). Recently there have been many outbreaks on Ebola in several countries of central Africa and due to these outbreaks there have been different types of field diagnostics as medical sophisticated support was required. (Feldman et al., 2003,). For an instance, the two outbreaks of Ebola hemorrhagic fever which took place in Gabon, 1996 resulted in mortality of 66% and 75% respectively in laboratory confirmed patients. (Courbet et al., 1999). Several diagnostic assays for Ebola infection are currently used and have been recently evaluated in patients in the field. (Ksiazek et al., 1999).

The different species of Ebola virus seem to cause somewhat different clinical syndromes, but it’s slightly difficult to observe them under perfect conditions, and it’s very rare that observations like this are done. (Feldman, Geisbert and kawaoka, 2007, p.129)

Using the symptoms Ebola can be identified, but before doing so it is investigated using so many procedures like: Antigen-capture detection tests, Serum neutralization tests, Reverse transcriptase polymerase chain reaction (RT-PCR) assay, Electron microscopy, Virus isolation by cell culture and Antibody-capture enzyme-linked immunosorbent assay (ELISA). Handling these can be highly dangerous and can be risky as these can be transmitted through direct contact (WHO, 2014).

1.6 Treatment methods for Ebola.

Due to its specific morphology, still the drugs and the therapies are not fully evaluated, however it is currently evaluating (WHO, 2014).At the same time Ebola can be prevented to its maximum if we follow necessary preventive techniques like raising the awareness of Ebola infection, safe burials and social mobilization (WHO, 2014).Different species of Ebola virus causes different symptoms but the opportunities for a good observation of the virus under good condition is very rare (Feldman et al., 2011).

The virulence of Ebola virus differs according to the species or strain which attacked the humans as well as non-human primates (Sanchez et al., 2011).among the Ebola’s genus infection rate of the Zaire Ebola virus and the Sudan Ebola virus rate differs, among these the Zaire Ebola virus has the highest case-fatality rates which is 60-90% (Guenno et al., 2011).lately due to some investigations done which included the observation of some attenuated vesicular stomatitis virus expressing the Ebola virus surface glycoprotein which previously has demonstrated efficiency as a vaccine against Ebola infections in rodents and monkeys (Feldman et al., 2007). It should be highly realized that workers such as doctors, nurses, scientists’ who work with direct contact with the victim too should be under consecutive care as Ebola is a directly spreading virus (Casillas, 2003).

1.7 Conclusion.

Moreover to summarize all what is said above we can say that Ebola is not a virus to be put down as it is highly dangerous and very harmful as it can easily spread which causes it to be deadly and also as it can keep rising leading to tragedy deaths. And to recall the past, it is said that Ebola was found in Africa and the name itself implies on the first outbreak which happened near the Ebola River and also there are five main types of Ebola viruses but among them the E.Zaire and the E.Sudan are the commonly found ones. Ebola is a class 4 pathogen belonging to the family Filoviridae as it causes severe hemorrhagic fever and various symptoms and this is currently incurable as there are no specific treatments or drugs available. Isolating the infected person, handling the preventive techniques carefully might reduce the spreading of Ebola, and finally to conclude it is in the future’s hand to find proper vaccine and drugs to stop Ebola.

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