Yellow fever is a viral infection spread by a particular type of mosquito. The infection is most common in areas of Africa and South America, affecting travelers to and residents of those areas. Symptoms of yellow fever include fever, headache, jaundice, muscle pain, nausea, vomiting, and fatigue. It is difficult to diagnose, especially during the early stages. Polymerase chain reaction (PCR) testing in blood and urine can sometimes detect the virus in the early stages of the disease. In later stages, testing to identify antibodies is needed (ELISA and PRNT). Yellow fever is prevented by an extremely effective vaccine, which is safe and affordable. A single dose of the vaccine is sufficient to grant sustained immunity and life-long protection against the disease. A booster dose of the vaccine is not needed. If you would like to find out more and receive a second opinion regarding your diagnosis and treatment, please contact us at secondopinions.com for your peace of mind.