Yellow fever is a serious disease transmitted by mosquitoes and in some areas the virus becomes endemic causing death of many people. It is a viral fever found largely in African countries and in some parts of South America. It is reported that about 50% of people affected with severe form of yellow fever die each year; however this can be prevented by vaccination.
Symptoms :
There will not be any signs and symptoms during the incubation period which may lasts for 3-5 days after you have contracted the virus. After 5 days the virus will assume an acute phase during which there can be mild-moderate symptoms. Some of the symptoms of acute phase of yellow fever are mild fever, headache, nausea, vomiting, body pain, drowsiness, muscle aches, acute pain in your back/knees, loss of appetite and redness in your eyes and face.
In the toxic phase, the symptoms will become worse. In some cases, toxic phase can be very dangerous causing life threatening symptoms. The skin color of the infected person becomes yellowish producing jaundice like symptoms. He may have severe abdominal pain followed by blood vomiting. Total urine output may reduce considerably indicating kidney failure. Some people may get bloody discharge from the nose and mouth. The heart function may collapse suddenly and for some there may be brain dysfunction. It can also cause grand mal seizures and coma in some people. Often, the toxic phase of the yellow fever will be fatal if not treated immediately. Due to prolonged infection the virus discharge plenty of toxins in the blood causing the above symptoms.
For many patients, the initial symptoms of acute phase will disappear for 5-7 days if proper treatment is taken. However for others the virus will enter into toxic phase followed by remission of initial symptoms. In the toxic phase, the patient will die within a week or two if the rate of toxicity is severe.