4 Things Pharmacists Should Know About Yellow Fever

Yellow fever virus is found in tropical and subtropical areas in South America and Africa. Additionally, yellow fever is related to the West Nile, St. Louis encephalitis, and Japanese encephalitis viruses.¹ The virus is transmitted to humans through the bite of an infected mosquito. Pharmacists can play an important role in educating patients traveling to areas with yellow fever about prevention strategies.

Here are 4 things pharmacists should know about yellow fever:

1. Yellow fever symptoms can range from mild to severe.

Most individuals who become infected with yellow fever virus develop a mild illness, and the incubation period is usually 3 to 6 days.¹ The initial symptoms include sudden onset of fever, chills, severe headache, back pain, general body aches, nausea, vomiting, fatigue, and weakness. About 15% of the cases can develop into a severe illness with symptoms, including high fever, jaundice, bleeding, shock, and multiple organ failure.¹

2. No specific treatments have been found to be beneficial.

Yellow fever patients should be hospitalized for supportive care and close observation. Treatment is symptomatic and includes rest, fluids, pain relievers, and antipyretics. Patients with yellow fever should not be treated with aspirin or other nonsteroidal anti-inflammatory medications, as these may increase the risk of bleeding. Yellow fever patients should be protected from further mosquito exposure by staying indoors and/or under a mosquito net for up to 5 days after the onset of fever to reduce the risk of further transmission.¹

3. Yellow fever vaccine is recommended for individuals traveling to certain areas.

Yellow fever vaccine is recommended for individuals younger than 9 months and older who are traveling to or living in areas at risk for yellow fever virus transmission in South America and Africa.¹ Yellow fever vaccination may be required for entry into certain countries.

It is important to note that Sanofi Pasteur, the manufacturer of the only yellow fever vaccine (YF-Vax) licensed in the United States, said that YF-Vax for civilian use is now unavailable until mid-2018 because of delays in the production process.² The vaccine may be available at some clinics for several months until the remaining supplies at the sites are depleted.

Sanofi Pasteur received approval from the FDA to make another yellow fever vaccine available in the United States under an investigational new drug program so that patients can continue to have access. The yellow fever vaccine Stamaril is manufactured by Sanofi Pasteur in France and has been distributed in more than 70 countries.² Additionally, it has comparable safety and efficacy to YF-Vax. Stamaril can only be provided to a limited number of clinics to meet the requirements of the IND program.² Pharmacists can assist patients with locating yellow fever vaccination clinics with YF-Vax and Stamaril through this site: wwwnc.cdc.gov/travel/yellow-fever-vaccination-clinics/search.³

4. Mosquito prevention strategies are important to prevent yellow fever.

Counsel patients to use mosquito bite prevention strategies when traveling to areas that have yellow fever. Recommend that they use an EPA-registered insect repellent containing DEET, picaridin, IR3535, or oil of lemon eucalyptus on exposed skin.¹ Patients should wear proper clothing (eg, long sleeves, long pants, and socks) outdoors to reduce the number of mosquito bites if the weather is appropriate.

References

1. CDC. Yellow fever. cdc.gov/yellowfever/index.html. Updated July 12, 2016. September 22, 2017.

2. CDC. Clinical update announcement: temporary total depletion of US licensed yellow fever vaccine addressed by availability of Stamaril vaccine at selected clinics. wwwnc.cdc.gov/travel/news-announcements/yellow-fever-vaccine-access. Updated July 24, 2017. Accessed September 24, 2017.

3. CDC. Search for yellow fever vaccination clinics. wwwnc.cdc.gov/travel/yellow-fever-vaccination-clinics/search. Accessed September 24, 2017.