Yellow Fever Vaccination

Yellow fever vaccine

Yellow fever can be an issue for travelers headed to certain parts of the world, particularly South America or Africa. If you think you might need a yellow fever vaccine for your destination, you should plan ahead of time to get vaccinated before your trip.

Thankfully, a safe and effective yellow fever vaccine has been available for more than 80 years, and once vaccinated, you’re protected for life.

For more information about vaccination requirements and recommendations for specific countries, the CDC Travelers’ Health page can help guide you through the process.

Where to get yellow fever vaccine      

Risk for acquiring yellow fever is dependent on your travel destination and season of travel; for example, according to the CDC, yellow fever has an elevated risk of transmission in West Africa during the end of rainy season, usually July to October. The risk for yellow fever infection in South America, on the other hand, tends to increase between January and March. (Learn more about the CDC’s recommendations for vaccination by country and season.)

Anyone traveling to the listed areas where there’s an increased risk of contracting yellow fever should be aware there’s only a select few locations to get the yellow vaccine in the United States. In fact, yellow fever vaccinations are only available in California, New Mexico, Oregon and Washington.

If you’re thinking of getting a yellow fever vaccination, contact a Pharmaca in one of these states. We provide the best medical immunizations for plenty of communicable and preventable diseases, such as yellow fever.

What is yellow fever?

The yellow fever virus is found in tropical and subtropical areas of Africa and South America, and is transmitted to humans by infected mosquitoes. Getting yellow fever is rare for US travelers, but it can still be a risk. Effects of the illness itself range from fever to aches and pains to severe liver disease with bleeding to yellowing skin (jaundice). The infection is diagnosed from lab testing, a person’s symptoms and travel history.

There is no medicine to treat or cure infection once a person contracts yellow fever.

What causes yellow fever?

Simply put, a virus carried by infected mosquitoes causes yellow fever. The virus is a single-stranded RNA virus that belongs to the Flavivirus genus. After the virus is transmitted, it replicates in regional lymph nodes and spreads via the bloodstream. Such widespread distribution can affect many areas of the body, including the bone marrow, spleen, lymph nodes, kidneys and liver, as well as other organs.

How is yellow fever spread?    

Infected mosquitoes are responsible for the transmission of yellow fever to humans. Certain species of mosquitoes are vectors for the disease and are responsible for it spreading to humans and primates, which serve as reservoirs for the disease.

Importantly, direct contact with other infected individuals does not transmit yellow fever. However, people with yellow fever are infectious and can transmit the virus to uninfected mosquitoes right before the onset of fever and for 3–5 days after the initial onset of symptoms.

Yellow fever symptoms

After a person contracts the virus, yellow fever incubates in the body for 3–6 days. During this time, many people do not experience symptoms. The first phase is when a person develops a milder set of symptoms.

Acute Phase

When symptoms of yellow fever do occur, the most common include:

  • Headaches
  • Muscle aches
  • Joint aches
  • Chills
  • Fever

In most cases, symptoms disappear after 3–4 days.

Toxic Phase

There’s a small percentage of people who then enter a second, more dangerous phase within 24 hours after the initial symptoms. The high fever returns and several other body systems are affected, usually the liver and the kidneys.

Symptoms of this this stage of yellow fever include:

  • Decreased urination
  • Abdominal pain
  • Vomiting (sometimes with blood)
  • Heart rhythm problems
  • Seizures
  • Delirium
  • Bleeding from the nose, mouth and eyes

This phase of the disease is often fatal, but only 15 percent of people with yellow fever enter this phase.

Yellow fever treatment

Unfortunately, there are no antiviral medications that treat yellow fever, so yellow fever treatment consists primarily of hospitalized supportive care.

If you have yellow fever, a doctor will recommend that you stay inside—away from potential interaction with mosquitoes that could transmit the disease to others. Once someone has had yellow fever, they’ll be immune to the disease for the rest of their life.

Yellow fever vaccination

The yellow fever vaccine is used to prevent infection. It causes the body to produce its own protection (antibodies) against the yellow fever virus.

The yellow fever vaccine is very safe, and the CDC recommends vaccination for all adults and children who will be traveling to high-risk areas. In fact, some countries require proof of immunization before entry.

Yellow fever vaccine side effects         

Any side effects people experience after getting the yellow fever vaccine are usually mild and go away in a few days. They may include:

  • Pain, swelling or redness at the injection site
  • Low fever

Serious yellow fever vaccine reactions are very rare.

Who should get the yellow fever vaccine

  • Children 9 months and older traveling to countries that require proof of yellow fever vaccination, or traveling to areas of South America and Africa where yellow fever is known to exist
  • Lab or medical personnel who may have been exposed to the yellow fever virus or vaccine virus

Who should not get the yellow fever vaccine

  • People with moderate or severe illness (e.g. severe cold, flu, or infection of the sinuses or lungs)
  • People with allergies or hypersensitivity to eggs, chicken and gelatin
  • Pregnant women, those who plan on becoming pregnant and nursing mothers
  • Those with weakened immune system (e.g. those with HIV/AIDS or another disease that affects the immune system)
  • People undergoing treatment with steroids (such as prednisone)
  • People with cancer or undergoing cancer treatment
  • People with a history of thymus disease, including myasthenia gravis, thymoma or prior removal of thymus gland

People should also be aware if they might have a severe, life-threatening allergic reaction to the yellow fever vaccine or any ingredient in the vaccine.