Yellow Fever Outbreaks 2023

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Last reviewed
June 2, 2023
Content Overview
Yellow fever outbreaks in June 2023 transmitted by infected mosquitoes in the Americas.

Yellow Fever Outbreaks June 2023

The yellow fever (YF) virus has been endemic in tropical areas of Africa and Central and South America for many years. The YF virus is an arbovirus of the flavivirus genus and is transmitted to humans by mosquitoes belonging to the Aedes and Haemogogus species. As of June 2, 2023, the World Health Organization (WHO) says forty-seven countries in Africa (34) and Central and South America (13) are either endemic to or have regions endemic to yellow fever, and various countries require arriving travelers to show proof of yellow fever vaccination.

Yellow Fever in The Americas

Yellow fever outbreaks in 2023 have been reported by the Pan American Health Organization (PAHO). As of April 25, 2023, human cases of yellow fever have been recorded in Bolivia (two cases) and Brazil (three cases) this year. In 2022, confirmed cases of yellow fever were reported in three countries in the Region: Bolivia (5 confirmed cases), Brazil ( 5 cases, including four deaths), and Peru (7 confirmed cases, including five deathsTherefore, the PAHO recommends that Member States maintain a yellow fever vaccine stockpile and consider fractional doses to respond to potential outbreaks. 

Africa Yellow Fever

In 2022, 12 WHO African Region countries reported confirmed yellow fever cases - Cameroon, the Central African Republic, Chad, Côte d'Ivoire, the Democratic Republic of the Congo, Ghana, Kenya, Niger, Nigeria, the Republic of the Congo, Sierra Leone and Uganda. Since 2021, a total of 203 confirmed and 252 probable cases, with 40 deaths and a CFR of 9%, have been reported. In addition, the Africa CDC reports recent yellow fever outbreaks at this link. For example, a. A yellow fever case was reported in Côte d'Ivoire on May 8, 2023, in a man from Cocody-Bengerville in Abidjan. His yellow fever vaccination status is unknown. And the U.S. CDC has issued various travel alerts for Africa, such as Nigeria, in 2022. In addition, the Africa CDC publishes yellow fever vaccination requirements as of May 30, 2023.

Brazil Yellow Fever

Brazil is experienced its largest-recorded yellow fever outbreak, says the PAHO. As a result, the U.S. Centers for Disease Control and Prevention (CDC) recommends that all travelers ≥9 months of age going to the entire states of Acre, Amapá, Amazonas, Distrito Federal (including the capital city of Brasília), Espirito Santo,* Goiás, Maranhão, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pará, Paraná, Rio de Janeiro (including the city of Rio de Janeiro and all coastal islands), the Rio Grande do Sul, Rondônia, Roraima, Santa Catarina, São Paulo (including the city of São Paulo and all coastal islands), and Tocantins and designated areas (see map) of the following states: Bahia and Piauí. Vaccination is also recommended for travelers visiting Iguaçu Falls. And the CDC published an Emerging Infectious Disease Synopsis, Volume 29, Number 3—March 2023, describing five yellow fever vaccine–associated viscerotropic disease (YEL-AVD) cases in two familial clusters during the 2017–2018 YF vaccination campaign in São Paulo state, Brazil.

Brazil's Anvis confirmed proof that yellow fever vaccination is required when visiting certain areas. As of May 1, 2023, AustraliaCDCHong Kong, and the United Kingdom have issued travel alerts regarding Brazil's yellow fever outbreaks.

Peru Yellow Fever

In 2022 in Peru, there were seven yellow fever cases reported in the departments of Junín (4 cases), Ucayali (2 cases), and Ayacucho (1 case). Of the seven confirmed reported cases, five patients died. Between EW 1 and EW 13 of 2023, 4 probable cases of yellow fever were reported, still under investigation.

Yellow Fever Vaccines

Various yellow fever vaccines are authorized as of June 2023.