How to Prevent Yellow Fever

A vaccine is your best bet

Show Article Table of Contents

Yellow fever is a potentially deadly mosquito-borne illness. So far, we don't have any antiviral medications that are effective in treating yellow fever. That makes prevention crucial for avoiding infections, deaths, and outbreaks. Fortunately, we do have an effective vaccine for preventing it.

Not everyone can be vaccinated, though. Those people who can't, especially if they live in one of the 47 countries where the disease is common, travel to one of those countries, or live near the site of an outbreak, must rely on other prevention methods.

The World Health Organization (WHO) is always working to increase the vaccination rate for those at risk and to contain outbreaks when they occur, which protects us all.

Yellow Fever Vaccine

Why Vaccinate

Statistics show why prevention with vaccination is important.

According to the CDC, the risk of infection for unvaccinated travelers to West Africa is approximately 50 per 100,000 people. Of those who become infected, one in five die. The odds of infection get worse if you happen to go there during an outbreak.

Who Should Get Vaccinated

If you're planning to travel to an area of Africa, South America, or Central America where yellow fever is endemic you should talk to your doctor about being vaccinated before you go. Some of those countries will not even allow you to enter without proof of vaccination.

Getting the vaccine is also important if you live near, or are traveling to, an area that's currently experiencing an outbreak. Outbreaks can happen in regions where the disease isn't normally found if an infected traveler brings it there and infects local mosquitoes who are capable of carrying the virus and infecting the people and animals they bite. (Yellow fever isn't spread directly from person to person, and only mosquitoes, humans, and other primates are able to carry it.)

To help you learn what vaccines you need when traveling, the CDC maintains a Travelers' Health page as well as a page with Yellow Fever & Malaria Information by Country.

Timing

Plan to get your vaccination well ahead of getting on a plane—it takes 10 to 14 days after the shot for your body to develop immunity.

A single vaccine protects you for at least 10 years, and the immunity may last for life.

Risks and Complications

The vaccine is inexpensive and considered relatively safe for most people. However, there are risks to consider.

Between 10 percent and 30 percent of people who get the yellow fever vaccine report mild symptoms afterward that last for about a week, such as:

  • Low-grade fever
  • Headache
  • Body aches

Serious complications, which are much more rare, include:

  • A hypersensitivity (allergy) response, with a roughly estimated incident rate of about 1.3 per 100,000 doses.
  • Yellow fever vaccine-associated neurological disease, with a rate of about 0.8 per 100,000 doses in those under 60, and slightly higher in those over 60.
  • Yellow fever vaccine-associated viscerotropic disease, which is similar to yellow fever itself, with a rate of about 0.3 per 100,000 doses in those under 60, and about 1.2 per 100,000 in those over 60, and a still higher rate for those over 70.

Contraindications

People with severe allergies to vaccine ingredients should not be vaccinated. Potentially problematic vaccine ingredients include:

  • Eggs and egg products
  • Chicken proteins
  • Gelatin
  • Latex (in the vial's stopper)

Other people who shouldn't get the vaccine include:

  • Babies under 6 months old
  • Babies 6 to 9 months old, unless they're in a high-risk area
  • Pregnant women, unless they're in a high-risk area
  • People with immunodeficiency, such as HIV disease
  • People on immunosupressant or immunomodulant drugs or similar therapies

The vaccine carries a precaution about safety during pregnancy and breastfeeding because it hasn't been studied enough to fully understand any risks it may pose.

If you're included in that list and traveling to a region where proof of vaccination is required, you'll need medical documentation for the requirement to be waived.

Vaccine Alternatives

For those people who can't be vaccinated, it's important to do what you can to prevent mosquito bites any time you're in an infected area.

To keep from being bitten, the CDC recommends:

  • Using insect repellent containing DEET, picaridin, IR 3535, or oil of lemon eucalyptus on any exposed skin.
  • Wearing long-sleeved shirts, long pants, and socks when outdoors, weather permitting; and applying repellent over thin clothing.
  • Being aware of peak activity patterns for the mosquito species known to transmit the virus (Aedes Aegypti and other Aedes species).
  • Staying in accommodations with screened or air-conditioned rooms.

It's especially important for an infected person to prevent mosquito bites, as they can infect an uninfected mosquito and therefore spread the disease.

Large-Scale Prevention

Prevention will always be the main goal for stopping the spread of yellow fever. That's because experts believe it can't be eradicated.

Why? Because it's prevalent in monkey and other primate populations in the regions where the disease is endemic. The main goal is, therefore, to achieve high levels of vaccination in those regions in order to prevent outbreaks of the illness.

WHO works to control yellow fever with vaccination programs. The organization's goal is an 80 percent vaccination rate in those 47 countries. By 2027, it expects more than one billion people will have been given the shot.

Organizations combatting yellow fever maintain an emergency stockpile of six million doses of the vaccine that is continually replenished so that they can act immediately when an outbreak is detected anywhere in the world.

WHO also recommends eliminating potential mosquito breeding sites by putting larva-killing chemicals in standing water. At one point, the virus-carrying mosquitoes had been successfully eliminated from most of Central and South America. However, they have moved back in and increased the risk of the disease there again. WHO says it's not practical to try eliminating mosquitoes from jungles and forests.

Was this page helpful?
Article Sources