Ebola Epidemiology

Epidemiology

United States: Only a handful of documented cases in the United States, currently there are none. On September 30, 2014, the first travel-associated case of Ebola was reported in the United States from an asymptomatic man going from Liberia to Dallas, Texas. He began being symptomatic about 5 days later and soon passed away.

Worldwide Epidemiology: "Ebola virus was first recognized when two outbreaks occurred in Zaire and in Sudan in 1976. Outbreaks of Ebola virus disease have been confined to Sub-Saharan Africa. An epidemic caused by the Zaire species caused several hundred cases in 1995 in Kikwit, Democratic Republic of the Congo, and the Sudan virus infected more than 400 people in Gulu, Uganda in 2000. The 2014-2015 Ebola epidemic, caused by the Zaire species of virus, is not only the first to occur in West Africa, but is far larger than all previous outbreaks combined" (UpToDate). 

2014-2015 outbreak in West Africa, "Although all previous Ebola outbreaks occurred in Central Africa, an epidemic began in the West African nation of Guinea in late 2013 and was confirmed by the World Health Organization (WHO) in March 2014. The initial case was a two-year-old child who developed fever, vomiting, and black stools, without other evidence of hemorrhage. The outbreak subsequently spread to Liberia, Sierra Leone, Nigeria, Senegal, and Mali. Sequence analysis of viruses isolated from patients in Sierra Leone indicated that the epidemic resulted from sustained person-to-person transmission, without additional introductions from animal reservoirs (UpToDate). 

As of May 10, 2015, the cumulative number of probable, suspected, and laboratory-confirmed cases attributed to Ebola virus is 26,759, including 11,080 deaths. These cases include over 860 infected healthcare workers, of whom approximately 60 percent have died. The magnitude of the outbreak, especially in Liberia and Sierra Leone, has probably been underestimated, due in part to individuals with Ebola virus disease being cared for outside the hospital setting.

In some previously infected areas ebola has been eliminated such as Liberia on May 9, 2015 but it is still a serious problem. Mortality rate is about 50% for this disease.

References: 

1.) Ebola Virus Disease (2014, October 27). UpToDate. Retrieved April 3, 2015, from http://jama.jamanetwork.com/article.aspx?articleid=1915432

2.) Ebola Virus Disease. WHO (2015, April) Retrieved April 10, 2015 from http://www.uptodate.com/contents/epidemiology-and-pathogenesis-of-ebola-virus-disease

3.) MedShare. (2014, July 1). Retrieved April 3, 2015, from http://www.medshare.org/donate/urgent-relief/ebola-basics