**4. Geographical distribution**

YF is present in both the rural and urban tropical areas of 45 endemic countries in Africa and Latin America, with a potential combined population of over 900 million individuals [20]. The vast majority of cases and deaths take place in sub-Saharan Africa, where yellow fever is a major public health problem occurring in epidemic patterns. Africa also experien‐ ces periodic yet unpredictable outbreaks of urban yellow fever. Thirty-two African countries are now considered at risk of yellow fever, with a total population of 610 million people, among which more than 219 million live in urban settings [21]. The countries in Africa and the Americas to be at the risk of yellow fever is given in text box 2 [22].

**Africa**

**America**

Central America Panama

time in the past 50 years [21].

Leone, Togo

Gabon, Rwanda

East Africa Ethiopia, Kenya, Somalia, Sudan, Tanzania, Uganda

Trinidad and Tobago, Venezuela

**Text Box 2.** Countries in Africa and the Americas at the risk of yellow fever

**Figure 1.** Yellow fever endemic countries in the tropical regions of Africa and America

West Africa Benin, Burkina Faso, Cape Verde, Coˆ te d'Ivoire, Equatorial Guinea, Gambia, Ghana, Guinea,

Central Africa Angola, Burundi, Cameroon, Central African Republic, Chad, Democratic Republic of the Congo,

South America Argentina, Bolivia, Brazil, Colombia, Ecuador, Guyana, French Guyana, Paraguay, Peru, Suriname,

The yellow fever endemic countries in the tropical region of Africa and America are shown in the map (Figure 1) [23]. YF is endemic in ten South and Central American countries and in several Caribbean islands. Bolivia, Brazil, Colombia, Ecuador, and Peru and Venezuela are considered to be at greatest risk. Although the disease usually causes only sporadic cases and small outbreaks, nearly all the major urban centers in the American tropics have been reinfested with *Ae. aegypti* and most urban dwellers are vulnerable because of the low im‐ munization coverage. Latin America is now at greater risk of urban epidemics than at any

Guinea-Bissau, Liberia, Mali, Mauritania, Niger, Nigeria, Sao Tome and Principe, Senegal, Sierra

Yellow Fever Encephalitis: An Emerging and Resurging Global Public Health Threat in a Changing Environment

http://dx.doi.org/10.5772/46041

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**Text Box 1.** Key Milestones in the History of Yellow Fever (Bryan et al., 2004) [18]


**Text Box 2.** Countries in Africa and the Americas at the risk of yellow fever

[20]. The vast majority of cases and deaths take place in sub-Saharan Africa, where yellow fever is a major public health problem occurring in epidemic patterns. Africa also experien‐ ces periodic yet unpredictable outbreaks of urban yellow fever. Thirty-two African countries are now considered at risk of yellow fever, with a total population of 610 million people, among which more than 219 million live in urban settings [21]. The countries in Africa and

the Americas to be at the risk of yellow fever is given in text box 2 [22].

**1648** An epidemic of probable yellow fever erupts in the Yucatan Peninsula (Mexico)

**1916** The Rockefeller Foundation begins its commitment to eradicate yellow fever.

*aegypti* was not present, suggesting other vectors.

**1937** Large-scale immunizations with the 17-D yellow fever vaccine are begun.

**Text Box 1.** Key Milestones in the History of Yellow Fever (Bryan et al., 2004) [18]

**1750** Griffin Hughes was the first to use the term " yellow fever " to describe the disease in his book

**1854** Luis Daniel Beauperthuy of Venezuela suggests that a mosquito might transmit yellow fever.

**1793** An epidemic in Philadelphia kills about 10% of the population and sparks debate between ''contagionists''

**1802** StubbinsFfirth, a Philadelphia medical student, begins self-experiments to disprove the theory of contagion.

**1880s** Yellow fever in Panama kills tens of thousands of French workers, causing Ferdinand DeLesseps to abandon

**1901** The Reed Commission publishes its definitive proof of the mosquito hypothesis based on the data obtained

**1902** William Crawford Gorgas supervises on the eradication of yellow fever from Havana by controlling *Ae.*

**1925** The Rockefeller Foundation opens a laboratory in Yaba, Nigeria, to investigate the etiology of yellow fever.

**1930** Max Theiler demonstrates that white mice are susceptible to yellow fever by intracerebral inoculation, which leads to a ''mouse protection test'' for seroepidemiologic studies and to an effective vaccine.

**1933** Fred L. Soper and colleagues report an outbreak of yellow fever in a rural area of Brazil in which *Ae.*

**1940s** Due to mass vaccination campaigns and efforts to remove *Ae. aegypti* breeding sites, urban YF was dramatically controlled in Africa, particularly in French speaking West African countries

**2002** The World Health Organization estimates that yellow fever affects each year up to 200,000 persons with

**1951** Theiler receives the Nobel Prize for his work that led to the discovery of the 17D vaccine.

**1927** The causative agent of YF disease, YFV, was first isolated from a Ghanaian patient named Asibi

**1881** Carlos J. Finlay of Havana publishes his hypothesis that a specific mosquito (*Cubex cubensis* now *Aedes*

**Year Description of events**

210 Encephalitis

and ''anti-contagionists.''

at Camp Lazear.

*aegypti*.

up to 30,000 deaths.

*aegypti*) might transmit yellow fever.

his attempt to build a canal across the isthmus.

The yellow fever endemic countries in the tropical region of Africa and America are shown in the map (Figure 1) [23]. YF is endemic in ten South and Central American countries and in several Caribbean islands. Bolivia, Brazil, Colombia, Ecuador, and Peru and Venezuela are considered to be at greatest risk. Although the disease usually causes only sporadic cases and small outbreaks, nearly all the major urban centers in the American tropics have been reinfested with *Ae. aegypti* and most urban dwellers are vulnerable because of the low im‐ munization coverage. Latin America is now at greater risk of urban epidemics than at any time in the past 50 years [21].

**Figure 1.** Yellow fever endemic countries in the tropical regions of Africa and America
