Exploring Factors Behind The Re-Emergence Of Communicable Outbreaks: The Case Of Ebola

Role of the Pathogenic Agent

Good health is one of the key concepts of wellbeing and each and every individual of the society has a right to obtain and retain good health. A community can ever attain optimal productivity and progress until each and every individual of the society has good health. However, having optimal healthy for each and every individual belonging to a particular community is an extremely difficult pursuit to achieve. There are a multitude of different external and internal factors that define the health status of a community. Diseases are the most influential factor out of the abundance of different factors that govern the health and well being status of a community (Biek & Real, 2010).

Now there are different kinds of diseases and each if the kind affects the health and well being of the community differently, hence there is a significant impact of each kind of disease on the collective health and wellbeing of the community. Now broadly categorizing the different kinds of diseases in two categories, disease can be either communicable or non communicable. Elaborating more on this concept, a non-communicable disease can be defined as the disease which has a slow progression and is not caused by an infectious agent. Although there are a vast majority of non-communicable diseases that are included in the list of public health priorities, the major threat of the collective health and wellbeing of the community is due to the vast majority of communicable diseases that overshadow the progress made by health care onto the overall health and welfare of the individuals any day (Coker et al., 2011). A communicable disease can be described by the diseases which are caused by an infectious agent, now the huge threat that communicable diseases impart on the community is due to the contagiousness of the disease which can easily turn into epidemics and pandemics, leading to a massive loss of lives. One of the extremely dangerous aspects associated with communicable disease is the fact that these can re-emerge after one successful event of controlling the outbreak. There are multiple factors that drive the re-emergence of a particular communicable outbreak, and each of the confounding factors imparts a significant effect (Dhama et al., 2015). This assignment will attempt to explore a few key factors associated with the re-emergence of a communicable outbreak taking the data from the authentic and reliable literature taking the example of one of the most deadly outbreaks, EBOLA.

EBOLA disease, as mentioned above has been one of the most deadly communicable disease outbreaks that the human society has seen in the last decade and this disease has been the cause behind the magnanimous number of deaths in the world. This disease is also known as the Ebola hemorrhagic fever that is caused by any of the EBOLA virus species. This contagious disease affects humans, nonhumans and primates like monkeys, gorillas and chimpanzees. The pathogen that causes this deadly disease is called the Ebolavirus that belongs to the family Filoviridae. Now, on a more elaborative note, this communicable disease causes acute and infectious hemorrhagic fevers which leads to fatalities or co-morbidities easily if adequate medical attention is not invested after immediate diagnosis (Feldmann, 2010). Elaborating more on the characteristics of the pathogen, the basic biological features of the pathogen includes an enveloped single stranded structure of the virus which also consists of unsegmented negative sense RNA. The viral species of this particular family have a characteristic filamentous feature of the thread viruses. The shape of the virus can appear as U, 6 or a standard snake like coiled feature. This virus can also sometimes appear as branch structure due to the presence of long non coding regions at its 3’ and/or 5’ ends . One of the primary factors behind the Ria merchants of this particular deadly virus is the presence of non coding regions in the 3’ and 5’ ends. According to the author is non coding regions contribute to the stability of the viral transcripts made inside the host system, due to the exceptional stability of the viral transcript it helps the viral strains overcome the preventative measures taken and re-emerge again and again. drift According to the most of the authors the stability that the non coding regions provide to the viral transcripts are the main contributing factor along with the various range of differences between the glycoproteins that's different viral strains produced due to very low genetic drift in the family is the main cause of different outbreaks again and again and has developed a niche for itself in the wild (Feldmann & Geisbert, 2011). There are seven key structural proteins which are essentially the membrane proteins that are present in the different strains of the Ebolavirus, out of which only one kind of the proteins have been identified, the lack of any structural knowledge regarding the proteomic of the virus and its infection mechanism is another reason why the outbreak of the disease cannot be completely prevented and continues to re-emerge from time to time.

Host analysis

The most virulent strains among the different types of the Ebola viruses is considered ti be the Ebola Zaire. The infection caused by the Ebola Zaire usually leads to death and this is th viral strain responsible for the most of the re-emergences. The first instance of outbreak caused by this particular viral strain was recorded in the year of 1972, after which the virus have been not reported until 1976. However, after the second appearance of this virus, it has been re-emerging from time to time and has been the cause behind the most massive of outbreaks. According to the most of the authors the Zaire strain has had the most of the reported fatalities, and close to 50% of the case fatality reports have been associated with the Zaire viral infections (Ftika & Maltezou, 2013).

According to Tok et al. (2015), different responses are found in the body due to multiple aspects of the virus–host interaction in the infected cells. This causes the initiation of different extracellular signalling events. It is difficult to answer how the virus influences the innate responses. It is challenging to answer this due to limited genes of interest. The most important approach used for host analysis of the Ebola infection is the transcriptomics. It has been found that the virus alters the host transcriptome at the organisation and cellular level. Various infected animals are competent in transmitting the infection to the humans including chimpanzees, gorillas, and fruit bats. Thus, there is effective transmission due to the high viral loads in the body fluids

In the host analysis studies by Team (2014), it was found that in 13 of the patients, Ebola virus antigen and/or antibody to this virus was confirmed. In 12 of the patients, the Ebola virus RNA was detected using the reverse transcriptase-polymerase chain reaction (RT-PCR) assays. These assays only targeted conserved regions that are glycoprotein genes. Further sequence DNA analysis showed that these strains of the Ebola Virus were hardly different from the strain found in 1976. A difference of 1.6% was found and yet caused severe outbreaks. Due to this unusual stability of the viral genome, the virus is occupying several niches in the wild type. Therefore, it is difficult for the public health professionals to diagnose and characterise the infections. Consequently, it is challenging to limit the event of emergence of the virus.  

These findings were supported by the findings of Osmond (2016). Initially it was found that there was no strong innate immune response by the EBOV infection after infecting the HepG2 cells. There was little induction found by the transcriptional profiles of cells. It may be due to through active suppression of the antiviral signalling in these cells. Further, experiments were conducted by destroying this inhibiting ability of the virus using mutation to the VP35 protein. Due to this mutation the virus could no more inhibit the IRF3 signalling in the host cells. The Ebola virus was no longer transcriptionally silent. In comparison to the wild type cells the infected cells containing the mutant version of the virus, both the ISGs and cytokines were unregulated. On the other hand the wild type cells showed robust innate response. Resistance to this mutation can be one of the reasons for the re-emergence of virus.  The study executed by Rasmussen et al. (2014) showed transcriptional differences observed in the patents who survived the patient when compared to the fatalities. It means that the patient susceptible to infection is accumulating the different pathogen response pathways. These pathways were accumulated irrespective of the number of viral genome copies.

There is a need of more such studies to indentify the mechanisms by which the host functioning are modified. There is a need of more insights into detailed pathogenesis in the host during the viral infection because the ongoing Ebola viruses are not susceptible to the existing antiviral strategies. 

According to the Gummow, 2010, a massive outbreak like the one caused by the Ebolaviruses cannot be only due to the pathogenecity of the viral strains, there are several environmental factors associated with the outbreak of EBOLA or its re-emergence. First and foremost, it has to be considered that this communicable disease was first reported in considerable severity in western Africa, and this disease is by no means a recent addition to the list of communicable diseases. This has been an old disease which has re-emerged, triggered by few key environmental factors. It has to be considered that the past outbreaks and its epidemic nature had been due to the lack of infection control activities in the health care facilities. The contagiousness of the viral transcripts is extreme as the structural membrane proteins found in the viruses are able to dissolve the membrane cells of the host. Hence, it has been a significant environmental factor that contributed and continues to contribute to escalating spread of the communicable disease.

Leach, Scoones & Stirling, 2010, have opined another very important factor associated with the personal hygiene and health status of the susceptible population. Considering the African population, the most of the Ebola outbreaks have been noticed in the remote and rural areas, where the socio-economic standards of the individuals are mostly below the poverty level; hence, as a result, the personal health status and hygiene of the susceptible population also suffers. The lack of proper hygiene and prevalent malnutrition contributes heavily to the susceptibility of the population of a given community which in turn increases the chances of re-emergence.

Another key external factor associated with the re-emergence of the Ebola virus is associated with the severe shortage of the health care staff. The infection control activities need to be extremely critical and extensive in order to stop the outbreak or prevent it for the future purposes. Lack of health care staff attending the patients in a health care facility performing proper patient isolation and other such related activities will eventually lead to extreme risk of  re-emergence (Leroy, Gonzalez & Baize, 2011).

It should be mentioned that Ebola virus first made its emergence in the year 1976, but the recent outbreak of the Ebola virus in the years 2014-2016 in West Africa has been considered as the largest. According to reports, the prevalence of Ebola had spread in the adjacent countries (Team, W. E. R. 2014).

After the outbreak of Ebola virus in West Africa, The World health organization had taken up certain strategic objectives in the year 2016. The strategic objectives are- ceasing the transmission of the Ebola virus in the countries affected, preventing the new outbreaks of the virus, essential health services and increasing resilience, fast track researches and development on Ebola.

WHO has essentially led the International population to develop the health care strategies for controlling the endemic disease. According to the study by (Baize et al., 2014) WHO has currently deployed more than 700 hundred staffs in about 63 districts in three of the most affected countries. According to ( Leroy et al., 2004), this is one of the largest operation that has been undertaken to in order to mitigate the spreading of Ebola. It is has been reported that WHO had collaborated with UN Mission for Ebola emergency Response (UNMEER).  WHO has reported have been collaborated with other UN agency partners such as WFP, UNICEF, OCHA, UNDP for setting up effective care programs for the Ebola affected countries. As per the report by ( Leroy et al., 2004) WHO have also partnered with the African Union, US centers for disease and control (CDC), The International federation for Red Cross (IFRC), Response Network and other partner of the Global outbreak alert. the collaborative approach had been taken to extend the key surveillance on the countries, such that the disease does not spread anymore. It has been reported by (Leroy et al., 2004) the in 2014, the WHO drafted a roadmap for the Ebola response. The response plan was made for helping the government and the associated partners for revising the operational plan regarding the prevention of Ebola in the countries.  It has been reported that the UN followed the ‘overview of needs and Requirements (ONR) and STEPP strategy’ for scaling up the Ebola response roadmap.

It has been found that the WHO STEPP strategy applied a phased operation in the worst affected areas and was found to be successful in tackling the largest Ebola outbreak, the world had ever witnessed. According to the report by (Kickbusch & Gleicher, 2012), the strategies helped in decreasing the cases in the densely populated areas and the affected rural areas. The current strategies have resorted to detailed micro planning which have shown that it is possible to eradicate the virus from remote lands like Liberia or the forests of New Guinea. Reports say the WHO has been working constantly along with its partners to turn the number of Ebola cases to Zero.

Going back to 2000-2001, where the Ebola hemorrhagic fever took a toll of about 50 lives in Uganda. At that time the CDC, in collaboration with WHO, The Uganda ministry of health and Medecins Sans Frontiers (MSF) participated in an International response against the Ebola virus.

According to report by (Busheh et al., 2015) another International response was also generated by the International centre for medical research in Franceville against the Ebola hemorrhagic fever that occurred in the Republic of Congo.

As per the information provided by the WHO, 20 cases of death were found to be because of Ebola in the Yambio County of the Southern Sudan.

Thus it can be seen clearly that the outbreak of Ebola had been increasing day by day till the largest outbreak took place in Africa.

It should be noted that Ebola virus might have spread several years before the actual outbreak of the disease. The Ebola outbreak in the Western Africa indicates that there should be alarming bells for these kinds of global threats. It should be mentioned that early detection of the virus, controlling the outbreak of the disease is managed by specialized centers for the disease control, present in almost every nation. The different disease control interventions have been taken up by organizations such as the Chinese centre for disease control and Prevention, European centers for disease prevention and control. As per the author ( Leroy et al., 2004), Australia have invested for the scope of the researches related to the prevention of Ebola. The re- emergence of the Ebola virus had rang the bell of concern in different countries, as the deadly virus can take a toll of thousands of lives. As per the Author (Bausch et al., 2007), the Ebola outbreak in Western Africa was just the beginning and if proper measures are not  taken this war can bring down the human species to the borderline .

The outbreak of Ebola hemorrhagic fever can be considered as the largest outbreak till date. The disease can be rare, but it can spread from person to person and may take the form of a pandemic. Therefore it is necessary to initiate the war cry against the deadly virus. The virus may spread mainly through the clinical staffs taking care of the virus infected patients (Karamouzian & Hategekimana, 2015). Early detection and proper interventions should be taken such that an uninfected person does not come in contact with body fluids of an infected person. According to (Baush et al., 2014) the virus can be transmitted while in febrile condition and also during the later stages of the disease. The virus can also spread from the dead bodies during the postmortem or the funeral preparations. The health care professionals and the care givers should be careful and should be able to identify the indication of the infection. Infection control and prevention policies should be strictly followed. It can be recommended for the presence of certain tools, like the severe respiratory tools for the detection of Ebola in work places (Karamouzian & Hategekimana, 2015). It is necessary to follow bio-safety precautions for the assessment of the infected samples in the laboratory (Karamouzian & Hategekimana, 2015). Proper disinfection, maintaining hygiene, disposal of hospital waste and measured burial practices can prevent the spreading of the viruses. A lot more researches are still required in the field of Vaccine preparation against the virus.

Conclusion:

On a concluding note, it can be stated that there are various risks associated with re-emergences of the communicable diseases of such magnitude. And any instances of the re-emergence can lead to situations where many lives can be lost. However, there are a myriad of external and internal factors associated with the re-emergences or general outbreak invasions. The viral strains responsible for these deadly diseases are not yet completely characterized, and there still are many structural features of the viral strains that are responsible for the extreme stability of the viral transcripts and increased pathogenecity. The identification of these key features of the Ebolavirus strains will open new horizons for preventative strategies for controlling the rate of re- emergences of the deadly diseases. Hence, there are many factors identified in this discussion and addressing each of the contributing factors identified in this situation can develop a preventative strategy that will effectively overcome the increasing arte of re-emergences.

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