Yellow fever remains a serious mosquito-borne disease in parts of Africa and the Americas. Recent estimates put the annual burden at 67,000–173,000 severe infections and 31,000–82,000 deaths, while surveillance reports show substantial differences between regions and years.
Table of contents
- Global burden and clinical severity
- African Region in 2023
- African Region in 2024
- The Americas in 2023 and 2024
- Vaccination campaigns and supply
- Travel-associated risk
Global burden and clinical severity
The World Health Organization (WHO) estimates that yellow fever causes 67,000–173,000 severe infections each year in Africa and the Americas. The same estimate places annual yellow fever deaths at 31,000–82,000. These are annual estimates reported in 2026, not a count from a single surveillance year. WHO, “Yellow fever - Global”
Approximately 15% of yellow fever infections progress to severe disease, according to the WHO’s clinical estimate reported in 2026. Among people who develop severe yellow fever, the case fatality can reach about 50% within 7–10 days. The CDC gives a related estimate: severe yellow fever cases have a 30–60% case-fatality rate. The WHO and CDC figures describe clinical severity estimates, rather than the observed fatality rate in one particular outbreak. WHO, “Yellow fever - Global”; CDC Yellow Book, “Yellow Fever”
The typical incubation period is 3–6 days. That interval is clinically important for travelers because symptoms can appear several days after leaving an area where transmission occurs. During epidemics, actual infections are estimated to be 10–250 times higher than reported figures, so confirmed-case totals should not be treated as a complete count of infections. WHO, “Yellow fever - Global”
Perinatal transmission of wild-type yellow fever virus is rarely documented. Two cases have been recorded in reviews through 2024, and both infants died of fulminant disease. This historical total is distinct from the annual burden estimates above. CDC Yellow Book, “Yellow Fever”
African Region in 2023
The WHO African Region recorded 99 confirmed and probable yellow fever cases during epidemiological weeks 1–52 of 2023. Those cases included 8 deaths, producing a reported case-fatality rate of 9.3%. The cases were reported across 15 countries. WHO, “Global yellow fever update, 2023”
The 2023 regional picture included several different surveillance categories. Three African countries experienced yellow fever outbreaks, 3 reported cases with epidemic potential, and 8 reported sporadic cases. These categories should not be added together as separate cases; they describe the countries’ epidemiological situations. WHO, “Global yellow fever update, 2023”
Country-level counts illustrate how unevenly the reported cases were distributed:
| Country | Reported cases | Deaths | Period |
|---|---|---|---|
| Cameroon | 42 | 5 | 2023, weeks 1–52 |
| Côte d’Ivoire | 11 | 0 | 2023, weeks 1–52 |
| Nigeria | 14 | 0 | 2023, weeks 1–52 |
| Democratic Republic of the Congo | 8 | 0 | 2023, weeks 1–52 |
| Central African Republic | 5 | 1 | 2023, weeks 1–52 |
| Equatorial Guinea | 2 | 0 | 2023, weeks 1–52 |
| Chad | 1 | 1 | 2023, weeks 1–52 |
The table covers the country counts specified in the WHO update; it is not a replacement for the regional total of 99 cases across 15 countries. The source reported 42 cases and 5 deaths in Cameroon, 5 cases and 1 death in the Central African Republic, and 1 case and 1 death in Chad. It also reported 11 cases and no deaths in Côte d’Ivoire, 8 cases and no deaths in the Democratic Republic of the Congo, 2 cases and no deaths in Equatorial Guinea, and 14 cases and no deaths in Nigeria. WHO, “Global yellow fever update, 2023”
Demographic information was available for subsets of the reported cases. Males were affected about 3 times more often than females among the 95 entries with sex data. Among the 88 entries with age data, 69% of cases were older than 15 years. These percentages describe the available entries, not necessarily all 99 cases. WHO, “Global yellow fever update, 2023”
African Region in 2024
For 2024, the African Region recorded 248 confirmed and probable yellow fever cases from 17 countries. The data were available on 7 June 2025, so this is a 2024 regional total reported with that data cutoff. Six countries accounted for 75% of the 248 cases. WHO, “Epidemiology of Yellow Fever in the African Region, 2024”
The largest reported country totals were 47 cases in Ghana, 41 in Uganda, 37 in Nigeria, 24 in Burkina Faso, 21 in Cameroon, and 17 in Chad. Together, those six reported totals equal 187 cases, while the WHO’s regional summary expresses their share as 75% of the 248-case total. WHO, “Epidemiology of Yellow Fever in the African Region, 2024”
Five deaths were recorded among the 2024 confirmed and probable cases: 2 in Cameroon, 2 in Uganda, and 1 in The Gambia. The reported case-fatality rate for confirmed and probable cases was 3.0%. Because the 2024 total includes both confirmed and probable cases, it should not be compared as if it used exactly the same case definition as every other dataset. WHO, “Epidemiology of Yellow Fever in the African Region, 2024”
The Americas in 2023 and 2024
The Americas reported 40 confirmed yellow fever cases in 2023, including 24 deaths. The resulting case-fatality rate was 60%. The cases came from 4 countries: Bolivia, Brazil, Colombia, and Peru. WHO, “Global yellow fever update, 2023”
The 2024 total for the Americas was higher: 61 confirmed cases and 30 deaths. The country breakdown was 8 cases and 4 deaths in Bolivia, 8 cases and 4 deaths in Brazil, 23 cases and 13 deaths in Colombia, and 19 cases and 9 deaths in Peru. These four country totals account for all 61 confirmed cases and all 30 deaths reported for the region in 2024. WHO, “Yellow fever - Global”
| Region and year | Cases | Deaths | Reported case-fatality rate | Case definition or scope |
|---|---|---|---|---|
| African Region, 2023 | 99 | 8 | 9.3% | Confirmed and probable; weeks 1–52 |
| African Region, 2024 | 248 | 5 | 3.0% | Confirmed and probable; data available 7 June 2025 |
| Americas, 2023 | 40 | 24 | 60% | Confirmed |
| Americas, 2024 | 61 | 30 | Not stated in the supplied WHO global update | Confirmed |
The comparison shows why geography, year, case definition, and reporting cutoff matter. A regional surveillance count is not interchangeable with the global annual estimate, and a reported case-fatality rate is not a universal clinical fatality rate.
Vaccination campaigns and supply
Vaccination activity reached large populations in 2023. About 62 million people were protected through yellow fever vaccination campaigns in Africa, while more than 184,000 people were protected through campaigns in Latin America and the Caribbean. About 17.4 million children were protected through routine yellow fever immunization in Africa, and more than 704,000 people were protected by reactive yellow fever vaccination there. WHO, “EYE Strategy 2023 Highlights”
Several national campaigns made up a substantial share of the African activity. Nigeria protected 18.7 million people through preventive mass yellow fever vaccination campaigns in 2023. Uganda protected about 9.5 million people in a multi-year preventive mass campaign. The Democratic Republic of the Congo was protecting more than 29.6 million people through preventive mass yellow fever vaccination combined with measles vaccination. WHO, “EYE Strategy 2023 Highlights”
Supply figures provide another view of prevention capacity. UNICEF procured 97.2 million yellow fever vaccine doses through the Eliminate Yellow Fever Epidemics (EYE) strategy in 2023. About 1.2 million doses were shipped to outbreaks during that year. The number procured and the number shipped to outbreaks measure different parts of the vaccine supply response and should not be combined as a single coverage figure. WHO, “EYE Strategy 2023 Highlights”
Travel-associated risk
Travel-associated reports show the potential severity of infection in people without documented vaccination. From 1970–2015, 11 yellow fever cases were reported in travelers from the United States and Europe returning from West Africa or South America. Eight of those 11 cases were fatal. Only 1 traveler had documented yellow fever vaccination, and that traveler survived. CDC Yellow Book, “Yellow Fever”
More than 37 travel-associated yellow fever cases were reported in unvaccinated travelers during 2016–2018. At least 15 European travelers were included among those cases, as was 1 American traveler to Peru. These are historical reports of travel-associated cases, not a current probability for every traveler. CDC Yellow Book, “Yellow Fever”
For an unvaccinated traveler spending 2 weeks in West Africa, the CDC’s estimated risk is 50 cases of illness per 100,000 travelers and 10 deaths per 100,000 travelers. For an unvaccinated traveler spending 2 weeks in South America, the estimated illness risk is 5 per 100,000 and the estimated death risk is 1 per 100,000. These are travel-risk estimates reviewed in September 2024, and they describe the specified 2-week stays rather than all destinations or trip lengths. CDC Yellow Book, “Yellow Fever”
| Scenario | Estimated illness risk | Estimated death risk | Measurement scope |
|---|---|---|---|
| Unvaccinated traveler, 2 weeks in West Africa | 50 per 100,000 | 10 per 100,000 | CDC estimate reviewed September 2024 |
| Unvaccinated traveler, 2 weeks in South America | 5 per 100,000 | 1 per 100,000 | CDC estimate reviewed September 2024 |
The travel figures, regional surveillance totals, clinical estimates, and vaccination counts answer different questions. Together they show the range of yellow fever statistics: estimated global burden, reported disease and deaths, prevention reach, vaccine logistics, and risk estimates for defined travel scenarios.