December 4, 2013
Sudan Reports Widespread Yellow Fever Outbreak, 14 Dead
Lawrence LeBlond for redOrbit.com - Your Universe Online
Field investigations carried out by the FMOH revealed that the initial suspected cases were reported among seasonal workers coming from the eastern states of Sudan who had traveled to West Kordofan for work in October. Subsequent cases were reported among locals in both West and South Kordofan states, following the arrival of the workers.
Blood samples that were collected during the field investigation tested positive for Yellow Fever by IgM ELISA Assay at the National Public Health Laboratory of the FMOH in Khartoum. The samples were retested at the Institute of Pasteur in Senegal and were confirmed to be that of Yellow Fever. Subsequent seroneutralizing (PRNT) testing by WHO researchers also confirmed presence of yellow fever.
The field investigation also found evidence of Aedes aegepty mosquitoes in the areas where the infected persons were found. A. aegepty is one vector that can sustain transmission of yellow fever.
WHO is assisting the FMOH to strengthen surveillance efforts and to conduct active case searches in and around the region. So far no suspected cases have been reported from any of the areas outside of where the initial outbreak occurred. The FMOH is now organizing a massive vaccination program against yellow fever in the affected areas to prevent further infection.
According to a WHO report, it is estimated that yellow fever infects between 840,000 and 1.7 million people in Africa each year, resulting in about 29,000 to 60,000 deaths.
An outbreak last year in the Darfur region of Sudan resulted in 849 suspected cases and 171 deaths. Around five million people were vaccinated against yellow fever in the five states of Darfur following the outbreak. In 2005, a yellow fever outbreak was also reported from the South Kordofan state, resulting in 615 suspected cases and 183 deaths. A vaccination campaign followed targeting about 1.6 million people in the region.
Yellow fever, also known as Yellow Jack, is an acute viral hemorrhagic virus that affects 20 percent of an area’s population where it is commonly found. Most cases only cause a mild infection with fever, headache, chills, back pain, loss of appetite, nausea and vomiting. In these cases, the infection generally lasts three or four days.
In about 15 percent of cases, sufferers can enter a toxic phase of the disease with recurring fever accompanied by jaundice due to liver damage and abdominal pain. Bleeding in the mouth, eyes and gastrointestinal tract is also common at this stage and vomit may contain blood. This toxic phase is lethal in about 20 percent of cases, making the overall mortality rate for the disease about three percent. In severe epidemic outbreaks, mortality may rise to 50 percent or more.
For those who survive their infection, they usually do so without any organ damage and they are provided with a lifelong immunity to the virus.