Can Yellow Fever Vaccination End Outbreaks

In the Region of the Americas, the risk of yellow fever outbreaks remains high in 2023, while vaccination coverage for this preventable disease has stagnated over the past decade. 

According to the Pan American Health Organization (PAHO) epidemiological update, confirmed cases of yellow fever were reported last year in several countries led by Bolivia (5 confirmed cases), Brazil (5 cases, including four deaths), and Peru (7 confirmed cases, including five deaths.

As of April 25, 2023, additional yellow fever cases have been recorded this year in Bolivia (two cases) and Brazil (three cases).

The PAHO says yellow fever is an acute viral hemorrhagic disease that can quickly become fatal.

Once contracted, the yellow fever virus incubates in the body for 3 to 6 days. Many people do not experience symptoms, but when these occur, the most common are fever, muscle pain with prominent backache, headache, loss of appetite, and nausea or vomiting.

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

However, a small percentage of patients enter a second, more toxic phase within 24 hours of recovering from initial symptoms.

About half of the patients who enter the toxic phase die within 7 - 10 days.

In addition to the Americas, various African countries have reported outbreaks in 2023.

The good news is effective and safe yellow fever vaccines have been available for over 80 years, and over 850 million doses have been distributed worldwide.

A single dose is enough to confer immunity and protection for life without needing a booster dose, says the PAHO.

In addition to immunizing the at-risk population, countries should vaccinate visitors entering at-risk areas.

And the Eliminate Yellow Fever Epidemics program, driven by PAHO, seeks to vaccinate nearly one billion people against yellow fever by 2026.

In the U.S., Sanofi Pasteur's YF-VAX® vaccine has been available since April 5, 2021.

The International Certificate of Vaccination or Prophylaxis, known as the yellow card, is issued after vaccination.

This vaccine is only available at authorized locations like Houston, Texas.