Yellow fever


Yellow fever is an acute viral haemorrhagic disease transmitted by infected mosquitoes. Most of the cases have mild illness and between 15% and 20% go into sever haemorrhagic phase.  Up to 50% of severely affected persons without proper case management will die from yellow fever. The annual estimated cases per year in at risk areas are 200 000, including 30 000 deaths. Over nine hundred million people are at the risk of being infected in the tropical areas of Africa and South America.  

Thirty three countries in Africa are at risk of yellow fever. Those countries located between 15 latitude North and 10 latitude South. The highly endemic areas in Africa belong to the western part of Africa. These areas reports almost annually to WHO. The eastern part of Africa that in the risk of yellow fever zone are not as endemic like west Africa but to the low immunity it has the largest epidemics in the continent. 

Sudan is the only country in Eastern Mediterranean Region in the yellow fever zone. Large epidemics has been reported in Sudan in 1940, 1959, 2003, 2005, 2012 and 2013. Sudan conducted yellow fever risk assessment exercise in early 2013 and confirmed that the  yellow fever virus is circulating in all parts of the country. The recommendation was including conduction of preventive  vaccination campaigns, in addition to introducing the vaccine in the routine child immunization programme. Furthermore, Saudi Arabia requires from those who travel from endemic countries to perform umrah and hajj a valid  yellow fever vaccination certificate. 

Currently, a single dose of yellow fever vaccine is sufficient for life and no need for booster doses. WHO recommended preventive campaigns as a strategy for yellow fever control in endemic countries with high risk of epidemics.