Less common modes of transmission include vertical transmission, which is transmission from mother to child during pregnancy or at birth. Transmission via infected blood products and through organ donation is also theoretically possible during times of outbreak, though no cases have yet been documented. The incubation period ranges from one to twelve days, and is most typically three to seven.Chikungunya is related to mosquitoes, their environments, and human behavior. The adaptation of mosquitoes to the changing climate of North Africa around 5,000 years ago made them seek out environments where humans stored water. Human habitation and the mosquitoes environments were then very closely connected. During periods of epidemics humans are the reservoir of the virus. Because high amounts of virus are present in the blood in the beginning of acute infection, the virus can be spread from a viremic human to a mosquito, and back to a human. During other times, monkeys, birds and other vertebrates have served as reservoirs. Three genotypes of this virus have been described, each with a distinct genotype and antigenic character: West African, East/Central/South African, and Asian genotypes. The Asian lineage originated in 1952 and has subsequently split into two lineages – India (Indian Ocean Lineage) and South East Asian clades. This virus was first reported in the Americas in 2014. Phylogenetic investigations have shown that there are two strains in Brazil – the Asian and East/Central/South African types – and that the Asian strain arrived in the Caribbean (most likely from Oceania) in about March 2013.
See also
Coalition for Epidemic Preparedness Innovations
Epidemiology of chikungunya

References
Works cited
Burt FJ, Chen W, Miner JJ, Lenschow DJ, Merits A, Schnettler E, Kohl A, Rudd PA, Taylor A, Herrero LJ, Zaid A, Ng LF, Mahalingam S (April 2017). "Chikungunya virus: an update on the biology and pathogenesis of this emerging pathogen". Lancet Infect Dis. 17 (4): e107–e117. doi:10.1016/S1473-3099(16)30385-1. PMID 28159534. Vairo F, Haider N, Kock R, Ntoumi F, Ippolito G, Zumla A (December 2019). "Chikungunya: Epidemiology, Pathogenesis, Clinical Features, Management, and Prevention" (PDF). Infect Dis Clin North Am. 33 (4): 1003–1025. doi:10.1016/j.idc.2019.08.006. PMID 31668189. S2CID 241044156. External links
Chikungunya fact sheet—from the World Health Organization (WHO)
Chikungunya outbreaks—from the World Health Organization (WHO)
Togaviridae—from the Virus Pathogen Database and Analysis Resource (ViPR)
"Chikungunya". European Centre for Disease Prevention and Control. 23 January 2008. Archived from the original on 5 August 2009. Retrieved 20 May 2013. Chikungunya in Cuba Archived 18 July 2014 at the Wayback Machine
Chikungunya: The key role of "innate immunity"