Role of Agents
Medical sciences in the world are facing many kinds of challenges especially related to the emergence of new disease. New viruses are being found at different regions of the world and finding their cure can be helpful. Many of these diseases are communicable and hence tend to spread at very fast rate. Communicable diseases are the ones that spread from one person to another with the variety of sources and through different mediums (Baize, et. al. 2014). This may include transmission through bodily fluids, airborne diseases spreads through virus in the contaminated air or when bitten by insects. Ebola Virus is one of the five known virus in the species of genus Ebolavirus and family Filoviridae order Mononegavirales. This disease causes severe hemorrhagic fever in mammals especially in humans. The fatalness of the disease can be understood by the fact that it has caused the largest numbers of deaths in between 2013-2015 and is considered as an epidemic in West Africa (WHO Ebola Response Team, 2014).
The vastness is illustrated by the fact that there were 28,616 suspected cases and around 11,310 deaths. This virus is a single member of the species Zaire ebolavirus. EBOV genome is a single-stranded RNA approx. 19,000 nucleotide long (Gire, et. al. 2014). EBOV is also recorded as a select agent, WHO risk group 4 Pathogen. It is requiring Biosafety Level 4-equivalent containment. There are five types of Ebola Virus that has been detected having the name from where they have actually originated. They are Zaire, Sudan, Tai forest, Reston and Bundibugyo. This report analyses the role of different agents in spreading the Ebola Virus diseases. Host and environment factors that led to spread of diseases have also been elaborated. Along with this the potential policy responses have been elaborated.
Every communicable disease needs some or the agents to get it transfer from one body to another. This virus is transmitted in human from animals. It also gets transmitted in the human population by human to human fluid exchange. At the time when people gets in contact with the infected person and if there is any exchange of fluids then the uninfected person can also get affected by this. This might be with the help of broken skin or mucous membranes (Baylor College of Medicine, 2018). This might be transferred by the help of surface or material like clothing or bedding which when gets contaminated with these bodily fluids. This is the reason why health workers gets frequently affected by this disease while treating the patients that have either confirmed or suspected EVD (Carette, et. al. 2011). This generally gets occurred because of close contact with infected person or not following infection precaution strictly. It is interesting to note that the funeral rites that include direct touch with dead body may also lead to Ebola virus transmission.
Role of Host and Environment Factors
Since the infected human plays a very serious role in the spreading of Ebola as it also gets transmitted through sexual means. In this condition safe sex needs to be practiced. It is better that the person who have been found positive with the virus should not practice sex for some time. This will save their partners from getting infected (Mate, et. al. 2015).
One of the most specific agents in this regards that is known for spreading this disease is the fruit bat. They have been considered to be as one of those agents that are responsible for this disease. According to the scientists fruit bats of the Pteropodidae family are the natural Ebola Virus hosts. Other family bats have not been diagnosed with the virus of this disease till now. When these bats sits or eats the fruits, their saliva gets mixed with the fruit and when any person eats it, they eventually get infected by Ebola virus. They are known to fly up to distant locations and make the fruits infected. The roles of these bats are extremely critical for the people that are living in forests and are dependent on such fruits for their livelihood (Lyon, et. al. 2014). For a very long period of time, it has been seen that these bats are the only sources for transmission of diseases but later researches have showed different kind of results.
Ebola is also transferred into a person by having close interaction with the secretion, other bodily fluids of infected animals or blood organs. These animals include gorillas, monkey, chimpanzees, porcupine and forest antelope etc. These animals have also been found dead in the forests. This mode of transmission is common for the people that are having close contacts with the animals (Gatherer, 2014). In the West Africa where the case of Ebola Virus has been detected the most is the area where high numbers of animals resides. This area is highly rich in terms of the variety of animal species. Close contacts with such animals has resulted in getting infected by this disease. There are many people in this region who eat the flesh of these animals. These tribal people are at extreme threat to get infected with EVD (Chertow, et. al. 2014). Many of these developed viruses are found in the excreta or urine of the infected animals that too in high concentration.
Along with this another major role in the transmission of this disease is played by the insects. These insects when bite the person who has got infected from the virus gets affected and when they bite a healthy person, they transmit the disease to them (Varkey, et. al. 2015). However the role of such insects in the transfer of Ebola has been on the lower side. Some of the traditional agents of diseases like mosquitos and flies have not played a major role in the transmission of EVD but their role cannot be totally ignored. This is because the people stay infectious till the time their blood contains the Ebola virus.
In case of communicable diseases there are different hosts that carry the virus of this disease. Like the other viruses Ebola virus survival depends on the host organisms. Fruit bats of the Pteropodidae family are known to be as the natural hosts for this virus. Researchers found out that there are three species of bat that did not showed any symptoms when get infected by disease. These bats have Ebola specific genetic sequence in their bodies which gives the immune response towards Ebola and showed no sign of Ebola (Chan, 2014). Interestingly human body are not considered as the host for this disease. This virus only gets spread in the body of the human when they get contaminated by some or the other source. Human species are not even the natural reservoirs of this disease. Apart from the specified fruit bats, there are no such hosts that have been found and scientists are still in research of this virus. Another fact is that cooking kills the Ebola virus hence butchering while preparing the ape or bat meat could have been the most probable reason of the spread of this disease (Muyembe-Tamfum, Mulangu, Masumu, Kayembe, Kemp & Paweska, 2012). However the major reasons for the spread of this disease have been the bodily transfer of this disease.
This virus while attacking living cell hijacks the machinery of the host cell for its own objectives. This is an obstacle that safeguards one cell from its environment. This virus takes benefit of non-specific engulfing process also known to be as the macropinocytosis. This helps the virus to be eaten by the wave like motion of the cell membrane (Miller, et. al. 2012). They create copy of itself that lead to cell death or incapability to work appropriately. They take use of the host cell’s membrane like a capsule to enter into some neighbouring cells. Since natural host such as fruit bats have gained immunity towards this disease hence infection does not gets spread to this disease.
The environmental factors also play a very important role in the spread of Ebola Virus. The climatic conditions and the type of habitat that is present in any region plays a very essential role in the spreading of this disease. In the West African countries where the number of forest regions is high acts as a favourable climatic condition for the spread of EVD. This is very high in the case of animals but not so high human. In order to understand the environmental factors that leads to growth of this disease. The first thing that needs to be understood is that Viruses are organisms that need biological hosts to remain active. Once the virus gets in contact with the host cells, their viral receptors get attached to the specific receptor in the plasma membrane (Ansari, 2014). As soon as the attachment is made genome of the virus gets integrated in the host DNA. Once the genome gets favourable environment, it rapidly divides itself by mutation. These glycol-proteins are exposed to environment and bind to host specific receptors. They play an important role in making communication among other cells and the outside environment.
In the West and South African region where the condition of the sanitation is poor and there is no availability of the pure water, the chances of getting this disease becomes high. It is also seen that people usually get this disease because of the scarcity of food and lack of sanitation facilities. The malnutrition has widened the problem as their body becomes one of the easiest prays for the virus of this disease (Sakurai, et. al. 2015). Their body becomes unable to fight hence making it more vulnerable to the attack. It is the inaccessibility of the government of these nations to provide basic requirements of the citizens have resulted in increase in the numbers of people who had got affected by this disease.
Apart from this, it is also seen that such type of filoviruses are highly common in the tropical African region especially in the humid rainforest regions. This can be seen by the fact humid rainforest like Philippines also acted as a favourable climatic condition where these viruses can grow (Fidel, Pjey, Jaugar, Cedrine, Miguel & Reyjomar, 2014). Place having similar temperature and climate will have positive effect on the spreading of the diseases.
World Health Organisation has already declared it as a disease that is highly critical. All the governments in various parts of the world are very much concerned about the spread of this disease especially its outbreak in August 2014. In response to control the epidemic WHO has made the centres in the local areas of Africa where the medical staffs have been clearly instigated to stay safe against getting contaminated with the virus.
It is to be understood that the policy failure has also been in terms of the ways in which countries have handled the situation related to health index. The policy response in this regards is first to remove the anxiety, misperception, rumours and fear especially in the capital cities of Guinea and Liberia. WHO has issued an alert on the importance of safety measures that needs to be taken and it has extended its support to laboratories. Governments have taken measures to have a medical check-up of all the people that are coming to any country from this region.
The deployed team by WHO contains people having expertise in different fields like laboratory services, clinical case management, epidemiology, experts in logistics that includes social mobilisation, medical anthropology and risk communication (World Health Organisation, 2015). As World Health Organisation stated that their purpose is to bring strong strategic response towards this epidemic. In order to control the outbreak, World Health Organisation deployed two mobile laboratories that can go in the regions where medical support is extremely poor. A cross border monitoring has been done on the borders where three nations converged. A leadership approach was adopted where the public approach towards Ebola has to be changed. Then the advisory to every company was laid off which aimed to suggest them that their employees have to keep extra safety while working as a team (Dixon & Schafer, 2014). Cultural leaders have been briefed about risk that carries with traditional beliefs and cultural practices, extensive population movement across borders or within nations, inadequate and in effective measures taken by people. The problem related to resource management has been identified so as to find the probable solutions to the problems existing in the traditional areas.
The policy has also been established which gives a limited code status for the patients that are suspected or confirmed Ebola Virus Disease. This status means that a code blue will not be stated for such patients at any stage of the disease. Resuscitative efforts have been done at the clinical level so as to provide advantage to the patients. These efforts should not be for the patients having advanced Ebola Virus Disease as it would not be so beneficial for them. A proper training is given to the staffs that are working in the areas where advanced form of EVD has been found (Gov.UK, 2018). Trained medical staffs identify and treat the people in advance when they are likely to cause respiratory or cardiac arrest so as to reduce the need of emergency response. People or patient participation in the responding to this epidemic becomes more crucial and should be involved in care discussions. Along with this the medical team circulate the discretion guide so as to give proper care to the EVD patients.
Conclusion
From the above report, it can be concluded that communicable diseases can spread from one person to another with the help of different types of agents. Ebola Virus is one such disease that has caused thousands of death all across the globe and has become an epidemic in South and Western Africa. In the spread of this disease the role of agents has been very crucial especially the fruit bats of Pteropodidae family, different types of animals and human activities themselves. A fruit bat of Pteropodidae family is the natural host to this virus. The humid climate supports the growth of such kind of virus. There are many teams sent in the infected region along with objective to give strategic response to epidemic that is spread in the area.
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