Assignment For Health Geography Research A Plague Epidemic

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Ebola Epidemic
The largest epidemic of Ebola virus disease (EVD) was experienced between December 2013 and April 2016 where it recorded more than 28,000 cases with more than 11,000 deaths in Guinea, Sierra Leone, and Liberia. Studying this epidemic in the West African countries has led to an understanding of the disease and generation of insights into its control. However, despite knowing the geographic distribution of this epidemic, the transmission or diffusion methods from animals and survivors over a wide area of West Africa is still unpredictable. Until this is established, any future outbreaks will have to be addressed the way this other outbreaks have been controlled. This includes, extensive surveillance, detection, contact tracing, isolation of the patients, proper and supportive clinical care, extensive efforts aimed at preventing and controlling the infection, safe burial and community involvement. Empirical studies that were conducted during the outbreaks have revealed that such epidemics can be prevented with a rapid response that will interrupt the transmission rate, but the big question is how health personnel and services are prepared for future outbreaks.
History and Geographic Distribution
There have been 23 Ebola outbreaks in West Africa since the 1970s. The 2013-2016 epidemic was the largest one to have been recorded in history where it is reported that the first human case involved a 2-year-old boy from Meliandou village in Gueckedou which is a forested area in southeastern Guinea (World Health Organization). An investigation carried on the death of the boy revealed that he fall sick on 26 December 2013 and died two days later. The cause of the infection is believed to be Zaire ebolavirus species whose origin is still unknown but scientists have said that it is likely to originate from an animal, possibly a bat.
Despite the first infection being from an animal, subsequent cases were as a result of human-to-human transmission. In all the outbreaks, the main transmission mode was direct personal contact with the blood or any body fluid from an infected person. By early March 2014, the infection had spread into neighboring regions of Gueckedou (Kissidougou and Macenta) and by 10th March 2014, cases of the infections were reported in the capital city of Guenea-Conakry. There occurred massive transmission rates in Guinea between 10th March and April that resulted in more than 150 new cases and due to lack of interventions, the infection became more entrenched in Guinea. This allowed to spread farther and faster within the country and beyond its boundaries to other countries. Towards the end of March, the infection was reported in the counties of Lofa and Margibi in Liberia and Kailahun district in eastern Sierra Leone in May 2014.
Although the first infection originated in Guinea, rapid infections occurred in Sierra Leone and Liberia followed by Nzerekore in Guinea. Despite having a large number of people crossing the western border between Guinea and Sierra Leone, incidences of Ebola infections were synchronized within Guinean prefectures but this was not done in the adjacent district of Kambia in Sierra Leone. This led to the transmission of the infection across national borders. A phylogenetic analysis that was done on this epidemic provided valuable insights into the origins of this virus and how the impact of migration by infected individuals. Genomic analysis on this epidemic has demonstrated that it arose after a single introduction from an animal reservoir. In addition, this analysis also revealed how infected people moved fast over long distances
Spread of the Epidemic
The rate at which the epidemic spread from one region to another varied among the three countries as well as the consequences were also different. The first epicenter to have been hit by this infection was Conakry, but the incidences remained relatively low throughout the period of the epidemic. The detection of the epidemic in Monrovia, Liberia was later after Conakry but three weeks after it was reported in the north central region of Liberia. Of the three epicenters, Freetown recorded the highest incidences of Ebola infections (both cases and per capita), but increases in case incidences in Western Sierra Leone was reported in full 12 weeks. The infection rate and impact in both countries has never been predicted so far.
The first attacks of the infections from Guinea to other countries as well as its spread to the epicenters indicated the epidemics growth periods in both countries. The periods were characterized by “prolonged, exponential increases in the numbers of cases and the numbers of infected districts”. The size of the epidemic was measured through the duration of the exponential growth and not the weekly growth of case incidences in both countries. Sierra Leone recorded the slowest geographic spread rate where the period lasted for 22 weeks with case incidences doubling after every five weeks. Liberia reported the fastest geographic spread rate where it lasted for 15 weeks with case incidences doubling in two and half weeks. Despite the origin being from Guinea, it recorded the shortest and fastest growth that lasted for nine weeks with case incidences doubling in every 2 weeks.
If the growth period could have continued in this rate in both countries, by 2nd November case incidences could have gone beyond 20,000, and if the growth rate could have continued into 2015, then more cases could have been reported. The number of case incidences peaked at 950 cases during the last week of September 2014. Guinea recorded a total number of 3358 confirmed cases, Liberia 3163 confirmed cases and Sierra Leone 8706 cases. Number of cases per 100,000 per capita were 32, 87, and 137 respectively (Cori et al.). This demonstrates that Sierra Leone suffered most based on the number of cases and in per capita cases. Although there were uncertainties in reporting accuracies, differences in epidemic magnitude as well as its effect among the countries were witnessed.
The rapid spread of Ebola does not only present a characteristic of number of cases but also that of geographic dispersal. An example is the outbreak in Aberdeen in the period of January and February 2015 where Ebola cases were confirmed in 24 people with the infection having originated from a single source. Later the infections developed into a disease during the incubation period. Aberdeen was quarantined and the second generation of the epidemic was expected to occur in this area but it happened in Bombali district which is...