World Health Organization

WorldHealth Organization

WorldHealth Organization

The provides information about differentdiseases that affect people in various parts of the world. This paperwill focus on the analysis of Ebola, Leishmaniasis, and Hepatitis B.The paper will focus on organisms that cause the three diseases,distribution, prevalence, environmental, social factors, andtreatment of the illnesses.

OrganismsCausing the Diseases

Ebolais a type of fever that is caused by virus. The fever is caused byEbola virus species that belong to the family Filoviridae and thegenus Ebolavirus(WHO, 2016). Leishmaniasis, on the other hand, is caused byLeishmania parasites. The occurrence of the illness can be attributedto protozoan parasites that belong to the genus Leishmania(WHO, 2016). Hepatitis B refers to a viral infection that is spreadin the infected blood. This infection is caused by hepatitis B virus.

Distributionand Prevalence

Ebolainfection is widely spread in the African countries, including SierraLeone, Liberia, Gabon, Uganda, and the Democratic Republic of Congo(Michaud &amp Kates, 2014). However, Liberia and Sierra Leone havethe highest prevalence rates of about 0.07 % and 0.049 %,respectively (Michaud &amp Kates, 2014). Unlike Ebola that is highlyprevalent in the African countries, Leishmaniasis affects people indifferent continents. It is estimated that over 350 million peoplehave been infected with Leishmaniasis (Michaud &amp Kates, 2014).These cases of infection are distributed in over 88 countries. Thedisease affects all people, irrespective of their age or gender.Hepatitis B is mainly distributed in East Asia and Sub-SaharanAfrica, where about 5-10 % of the adults in these areas suffer fromchronic infection (WHO, 2016). Other areas that have been found tohave high prevalence rates include central as well as Eastern Europe.About 2-5 % of the general populations in the Middle East also sufferfrom Hepatitis B. Although the disease is also quite common in theU.S., the prevalence rates are less than those reported in otherparts of the world.

Environmentaland Social Factors

Thenatural environment contributes to the spreading of Ebola since theclimate in the affected African countries favors the growth andmultiplication of the virus. In addition, the affected countries arecharacterized by frequent floods that take raw sewage and the virusto residential areas (Alexander, 2015). Some of the key socialfactors that have contributed towards the spread of Ebola includewar, uncontrolled growth in population, and poverty. These socialconditions result in a rapid spread of disease due to the lack ofresources and the knowledge on how to control its prevalence(Alexander, 2015).

Areasthat are affected by Leishmaniasis are characterized by environmentaland climatic conditions that facilitate the multiplication ofLeishmania.For example, the growth of the pathogen is favored by conditions inthe Mediterranean basis, heavy rains, 600 meters above the sea level,and 15-38 °C range (WHO, 2016). Poverty is a social factor thatlimits the capacity of people in the affected areas to control thespread of the virus.

Thespread of hepatitis B is not significantly affected by the naturalenvironment. However, regions with high levels of humidity experiencea high prevalence rate. This phenomenon has been attributed to theincrease in aflatoxin in cereals (WHO, 2016). Social factors thatcontribute to its spread include poverty and poor sanitaryconditions.


Thereis no treatment for Ebola, but it is a manageable disease. Successfulrecovery can be achieved through the provision of intravenous fluid,balancing of electrolytes, maintenance of oxygen status, andeffective treatment of opportunistic infections (WHO, 2016).Leishmaniasis is mainly treated through medication. Some of the keydrugs that have been shown to cure the illness include sodiumstibogluconate, heat therapy, and cryotherapy (WHO, 2016). Thetreatment of hepatitis B varies depending on its severity. Commonmethods of treatment include antiviral drugs (such as entecavir andadefovir), interferon alfa-2b, and liver transplant (WHO, 2016).


Mostof the infectious diseases affect all people, irrespective of theirage and gender. However, their prevalence in different parts of theworld is highly influenced by environmental as well as socialfactors. Most of the viral diseases (such as Ebola) have notreatment, but patients can recover successfully with propermanagement.


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Michaud,J. &amp Kates, J. (2014). Measuring the impact of Ebola: Will itreach 1.4 million? KFFOrganization.Retrieved September 16, 2016, from

WHO(2016). Health topics. WHO.Retrieved September 16, 2016, from

WHO(2016, July). Media Center: Hepatitis B. WHO.Retrieved September 16, 2016, from