yellow fever
noun
: an acute infectious disease that is endemic in sub-Saharan Africa and tropical South America, is marked by symptoms (such as fever, muscle pain, and headache) of sudden onset which typically resolve within a few days but are sometimes followed by more serious symptoms (such as jaundice, high fever, and hemorrhage), and is caused by a flavivirus (Orthoflavivirus flavi) transmitted especially by the yellow-fever mosquito
Examples of yellow fever in a Sentence
Recent Examples on the Web
The species, which originated in Africa and continues to spread throughout Sacramento and Yolo counties, can carry dengue, Zika, yellow fever and chikungunya, diseases that can be life-threatening to humans.
—
Reeti Malhotra,
Sacbee.com,
1 July 2026
Conditions are ripe for waterborne infections like dengue, yellow fever and malaria to spread.
—
ABC News,
30 June 2026
Some mosquitoes can spread dengue, Zika, yellow fever, chikungunya, West Nile virus and other illnesses.
—
Kurt Knutsson,
FOXNews.com,
12 June 2026
Debug’s request to use Wolbachia against a particular species of mosquito called Aedes aegypti — responsible for spreading diseases like dengue, yellow fever, and the Zika virus — is currently pending approval from the EPA, and is open to public comment until June 5.
—
Joe Wilkins,
Futurism,
4 June 2026
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Reeti Malhotra,
Sacbee.com,
1 July 2026
Conditions are ripe for waterborne infections like dengue, yellow fever and malaria to spread.
—
ABC News,
30 June 2026
Some mosquitoes can spread dengue, Zika, yellow fever, chikungunya, West Nile virus and other illnesses.
—
Kurt Knutsson,
FOXNews.com,
12 June 2026
Debug’s request to use Wolbachia against a particular species of mosquito called Aedes aegypti — responsible for spreading diseases like dengue, yellow fever, and the Zika virus — is currently pending approval from the EPA, and is open to public comment until June 5.
—
Joe Wilkins,
Futurism,
4 June 2026
See All Example Sentences for yellow fever
Cite this Entry
“Yellow fever.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/yellow%20fever. Accessed 5 Jul. 2026.
Copy CitationMedical Definition
yellow fever
noun
: an infectious disease of sudden onset that is endemic in sub-Saharan Africa and tropical South America, is caused by a flavivirus (Orthoflavivirus flavi) transmitted especially by the yellow-fever mosquito, and is marked by acute symptoms (such as fever, muscle pain, headache, and nausea) which typically resolve within a few days but are sometimes followed by more serious symptoms (such as jaundice, abdominal pain, high fever, hemorrhage, and kidney impairment) which may lead to death
Few Americans realize that yellow fever was not always a disease of the faraway tropics. In 1878, an outbreak of yellow fever—the virus carried to the United States in mosquitoes from Africa—killed 20,000 people in the Mississippi Valley.—Mary Roach, The New York Times Book Review
Mary Roach, The New York Times Book ReviewAlthough mass vaccination campaigns in Africa between the 1940s and 1960s led to the near disappearance of yellow fever, inadequately immunized populations and urbanization set the stage for the disease to reemerge. By the 1990s, there were an estimated 200 000 annual cases, with 30 000 deaths.—Clem Spalding, The Journal of the American Medical Association
Clem Spalding, The Journal of the American Medical Associationcalled also yellow jack
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