What is yellow fever?
Yellow fever is a viral disease caused by the bite of a mosquito. Many countries still require visitors to be vaccinated for it before entering.
Yellow fever is found mainly in certain areas of Africa, Central America, and South America. In South America, infections happen only every now and then. They occur usually among forestry and agricultural workers or in travelers to jungle areas. But recent outbreaks have been reported in and around major cities in Brazil. In Africa, infections happen mostly in the tropical areas of western and central Africa. But they also happen in cities and jungle areas.
What causes yellow fever?
Yellow fever is caused by a virus (flavivirus). The virus is passed on to people through the bite of a daytime-biting mosquito (Aedes aegypti).
What are the symptoms of yellow fever?
Each person may have slightly different symptoms. The following are the most common symptoms:
Flu-like symptoms, such as headache, vomiting, and backache
Bleeding of the gums
Yellowing of the skin or eyes (jaundice)
Symptoms usually happen within 3 to 6 days after you are exposed to the virus. Symptoms may look like other health problems. Always see your healthcare provider for a diagnosis.
How is yellow fever diagnosed?
Your healthcare provider will ask about your past health and travel history for dates and exact locations. You will also need an exam. Blood tests can also help with a diagnosis.
How is yellow fever treated?
Treatment will depend on your symptoms, age, and general health. It will also depend on how severe the condition is.
Treatment is aimed at controlling your symptoms. This includes rest and plenty of fluids. You may also need to take medicine to help relieve fever and aching. You should not take aspirin or nonsteroidal anti-inflammatory medicines such as ibuprofen or naproxen. These may raise the risk of bleeding.
You should protect yourself from mosquitoes during the illness. This may mean staying indoors or under a mosquito net. This will help keep you from passing the disease on to other people.
What are possible complications of yellow fever?
Most people who get yellow fever do not have complications. They may not even know they have had the disease. Some people who get it may have some weakness and fatigue for a few months after symptoms go away. If severe disease happens, death is possible.
What can I do to prevent yellow fever?
A vaccine is available for yellow fever. The disease no longer happens in the U.S. But talk with your healthcare provider to see if you need the shot before visiting areas where yellow fever still exists. People who have had yellow fever develop lifelong immunity. The World Health Organization recommends a one-time yellow fever vaccine, instead of a vaccine every 10 years.
Not being bitten by mosquitoes is another important part of preventing yellow fever. Use mosquito repellant and cover exposed skin when traveling in areas where yellow fever occurs.
When should I call my healthcare provider?
Call your healthcare provider right way if your symptoms get worse or you have new ones.
Key points about yellow fever
Yellow fever is a disease caused by a virus passed on through the bite of a daytime-biting mosquito.
Yellow fever happens only in certain areas of Africa, Central America, and South America.
The disease causes flu-like symptoms, slow and weak pulse, bleeding of the gums, bloody urine, and yellow skin (jaundice).
Treatment is aimed at controlling the symptoms. It includes rest and plenty of fluids. You may also need to take medicine to help relieve fever and aching.
A vaccine is available to prevent yellow fever. You may need it before traveling to some tropical countries in Africa, Central America, or South America.
Tips to help you get the most from a visit to your healthcare provider:
Know the reason for your visit and what you want to happen.
Before your visit, write down questions you want answered.
Bring someone with you to help you ask questions and remember what your provider tells you.
At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
Ask if your condition can be treated in other ways.
Know why a test or procedure is recommended and what the results could mean.
Know what to expect if you do not take the medicine or have the test or procedure.
If you have a follow-up appointment, write down the date, time, and purpose for that visit.
Know how you can contact your provider if you have questions.
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