Source Lancet Infect Dis. 2011;11:622-32 via CDC
# 6681
For three weeks the newshounds on FluTrackers (among others) have been keeping track of a disease outbreak in Sudan that has claimed several dozen lives.
Today, the World Health Organization’s regional office for the Eastern Mediterranean has posted the following notice (h/t Ronan Kelley on FluTrackers), indicating they’ve been notified of a yellow fever outbreak in that country.
Yellow fever hits Central and South Darfur
29 October 2012 – Sudan’s Federal Ministry of Health has notified the World Health Organization (WHO) of a yellow fever outbreak in seven localities in Central and South Darfur. Since the first week of October, a total of 84 suspected cases, including 32 deaths, have been reported from the districts of Azoom, Kass, Mershing, Nertiti, Nyala, Wadi Salih and Zalingei.
The Federal Ministry of Health has said that the immediate priority is to control the vector, reinforce the disease surveillance system and raise public awareness of prevention and control of this disease. Preparations for a mass vaccination campaign are underway to vaccinate the at-risk population in Darfur.
Yellow fever is spread by mosquitoes. There is no specific treatment for yellow fever, only supportive care to treat dehydration and fever, and blood transfusion, if and when needed. It is a preventable disease with symptoms and severity varying from case to case. Protective measures such as the use of bednets, insect repellent and long clothing are considered the best methods to contain an outbreak.
Vaccination is the single most important measure for preventing yellow fever.
The Federal Ministry of Health, WHO and other health partners are working on the ground to ensure timely containment of the outbreak.
Yellow fever (aka Yellow Jack) is a viral disease transmitted by the Aedes mosquito (and others). There is a relatively safe, and effective, vaccine available and travelers to parts of equatorial Africa and South America are often advised to get it.
The CDC’s 2012 Yellow Book describes the clinical presentation this way:
Asymptomatic or clinically inapparent infection is believed to occur in most people infected with YFV. For people who develop symptomatic illness, the incubation period is typically 3–6 days.
The initial illness presents as a nonspecific influenzalike syndrome with sudden onset of fever, chills, headache, backache, myalgias, prostration, nausea, and vomiting. Most patients improve after the initial presentation.
After a brief remission of hours to a day, approximately 15% of patients progress to a more serious or toxic form of the disease characterized by jaundice, hemorrhagic symptoms, and eventually shock and multisystem organ failure. The case-fatality ratio for severe cases with hepatorenal dysfunction is 20%–50%.
In the 18th and 19th century Yellow fever caused major epidemics in Europe and in the United States, up the Atlantic seaboard and as far north as New England (Boston was hard hit in 1780, and Philadelphia saw several thousand deaths in 1793).
Yellow Fever has been cited as one of the primary reasons why the French abandoned their attempt to build a Panama canal in the late 1800’s, as the combined burden of Yellow Fever and Malaria reportedly claimed the lives of more than 20,000 construction workers.
For more on the fascinating history of `Yellow Jack’, I would point you to Ian York’s excellent Mystery Rays blog, where he gives us some terrific background in:
Yellow fever, stasis, and diversification
The deadliest, most awe-inspiring of the plagues
The good old days
While currently not a threat in Europe and the United States, yellow fever is on the radar screens of some epidemiologists as climate change, and the spread of suitable vectors, continue.
This from Eurosurveillance in 2010, and it is an excellent overview of the issue.
Eurosurveillance, Volume 15, Issue 10, 11 March 2010
Yellow fever and dengue: a threat to Europe?
P Reiter
The introduction and rapidly expanding range of Aedes albopictus in Europe is an iconic example of the growing risk of the globalisation of vectors and vector-borne diseases.
The history of yellow fever and dengue in temperate regions confirms that transmission of both diseases could recur, particularly if Ae. aegypti, a more effective vector, were to be re-introduced. The article is a broad overview of the natural history and epidemiology of both diseases in the context of these risks.
You can find more information on yellow fever at these websites:
http://www.cdc.gov/yellowfever/
