Yellow Fever

Yellow Fever

This post is the continuation for the flavivirus which I am going to talk about another disease cause by the Flavi family that greatly affects the lives of humans.

Yellow fever is an acute viral disease. It is an important cause of hemorrhagic illness in many African and South American countries despite existence of an effective vaccine. Yellow fever virus is transmitted by mosquitoes to human beings. The virus is also preserved in mosquito eggs through their incubation period, thus ensuring existence of the virus each year. Yellow fever is located only in Africa and South America.

Symptoms and outcome: http://www.safely.travel/wiki/images/2/2e/Global_distribution_of_Yellow_Fever.gif

Although some people experience no symptoms, others enter an acute phase, characterized by fever, muscle pain (especially backache), shivers, loss of appetite, nausea and/or vomiting. An indication of yellow fever infection is that the high fever is associated with a relatively slow pulse. After 3 or 4 days, most patients improve, but an estimated 15% enter a toxic phase, marked by a reappearance of fever, jaundice, abdominal pain, vomiting, and bleeding from the eyes, nose, mouth, vomit, and feces. Half of these patients in the toxic phase die within 10-14 days.

Prevention and management

A yellow fever vaccine is available and should be taken by travelers to endemic areas. It is a safe, effective live virus vaccine that has been used for several decades and confers immunity for 10 years or more. Side effects occur in very few vaccines. Four groups of people should not receive the vaccine: infants under 6 months, pregnant women, persons hypersensitive to eggs (the vaccine is developed in embryonic eggs), and immunosuppressed persons.

http://www.cambridgenetwork.co.uk/object/news/43564/img/mosquito_color_index.jpg

Because the virus is transmitted by mosquito, effective protection against mosquitos results in effective protection against yellow fever. This includes the use of insect repellant, protective clothing, and mosquito netting.




This picture states the number of people infected with yellow fever from 1980 to 2007.

http://www.who.int/immunization_monitoring/diseases/YF_coverage.jpg

This video below tell us that yellow fever is no laughing matter hence when there was a outbreak of yellow fever in brazil in 13 January 2008, many people were not immune to this virus hence there was a long to queue of people who needed vaccination of the virus.