Chikungunya virus is widespread throughout the tropics, where it causes recurrent outbreaks of chikungunya fever. In recent years, outbreaks have afflicted populations in East and Central Africa, South America and Southeast Asia. The virus is transmitted by Aedes aegypti and Aedes albopictus mosquitoes. Chikungunya fever is characterized by severe arthralgia and myalgia that can persist for years and have considerable detrimental effects on health, quality of life and economic productivity. The effects of climate change as well as increased globalization of commerce and travel have led to growth of the habitat of Aedes mosquitoes. As a result, increasing numbers of people will be at risk of chikungunya fever in the coming years. In the absence of specific antiviral treatments and with vaccines still in development, surveillance and vector control are essential to suppress re-emergence Nature Reviews Disease Primers | (2023) 9:17 2 0123456789();: PrimerWith the increasing global distribution of the Aedes mosquitoes and their ability to adapt to urban settings, the urban transmission cycle is increasingly important. Here, during a blood meal on an infected person, the female mosquito ingests the virus, which infects various mosquito tissues, including the salivary glands. During a subsequent blood meal by the infected mosquito, the virus is deposited in the skin of an uninfected person along with mosquito saliva, infecting the person and perpetuating the viral replication cycle 14 . Phylogenetic analysis identified three distinct lineages corresponding to their respective geographical origin: West African, East Central South African (ECSA) and Asian lineage 15,16 . The ECSA lineage is further divided into two clades: ECSA1, which consists entirely of ancestral CHIKV sequences, and ECSA2, which contains sequences from the Central African Republic, Cameroon, Gabon and the Republic of Congo 17,18 . Since its discovery in 1952, CHIKV has been reported to be circulating and causing sporadic outbreaks in sub-Saharan Africa. In 2004, an ECSA CHIKV strain emerged in Kenya and subsequently spread to the Indian Ocean Islands, where it caused outbreaks of an unprecedented magnitude, particularly in La Réunion [19][20][21][22][23][24] . The extent of this outbreak has led to the emergence of a fourth phylogenetic lineage termed Indian Ocean lineage, which has subsequently dispersed to Asia and India 25 and caused autochthonous transmission (local disease spread) in Mediterranean Europe (Italy and France) 26,27 .In December 2013, another major outbreak occurred when a strain from the Asian lineage emerged for the first time on the Caribbean Saint Martin Island, from where the virus spread to more than 50 countries of the South American continent, causing a conservatively estimated 1 million infections 28,29 . In 2014, the ECSA lineage was reported in Northeast Brazil, where it continues to circulate as the most prevalent strain today 30 .Most of the Indian Ocean lineage is characterized by an adaptive mutation in the E1 glycopr...