Chikungunya seroprevalence, force of infection, and prevalence of chronic disability after infection in endemic and epidemic settings: a systematic review, meta-analysis, and modelling study

Understanding the Transmission Dynamics of the Chikungunya Virus in Africa

“…a-c), followed by the ECSA, Asian, and WA lineage of 4.44 × 10 −4 , 4.178 × 10 −4 and 2.84 × 10 −4 subs/nt/yr, respectively. A study conducted by Volks et al in 2010 obtained comparable evolutionary rates, which showed a notable difference between enzootic lineages having a lower evolutionary rate than epidemic lineages [77]. Here, we have included South American ECSA strains in the phylogenetic analysis, which likely contributed to the difference in rates observed in the aforementioned study.…”

“…CHIKV is a single-stranded, positive-sense RNA virus, which has evolved as a quasispecies with geographically distinct variants [76]. Since the first identification in East Africa in 1953, the ECSA genotype initially circulated in east, southern, and central regions of Africa and has since spread to cause significant outbreaks in Asia and the Americas [77]. The ECSA genotype comprises three clades; Clade 1 (ancestral east and southern Africa strains), Clade 2 (Central African strains), and Clade 3 (Indian Ocean lineage) which has disseminated from Eastern Africa to Indian Ocean Islands, subsequently spreading to southeast Asia, Oceania, and Europe (Figure 2.…”

“…The ECSA lineage has also been detected in West Africa, isolated from a bat sample in Senegal in 1963, suggesting dissemination beyond its geographical origin and possible spatial overlap of the two lineages. The potential coexistence of the WA and ECSA genotypes in West Africa emphasizes the region's complex CHIKV dynamics however, this was a singular occurrence with no ECSA lineage strains detected since [77].…”

Programmatic considerations and evidence gaps for chikungunya vaccine introduction in countries at risk of chikungunya outbreaks: Stakeholder analysis

“…Passive surveillance methods currently used in many settings only pick up clinical cases of chikungunya presenting to hospital, resulting in an under diagnosis of asymptomatic and less severe infections. Analysis of age-stratified seroprevalence data is a useful method for estimating long-term average infection burden [ 4 ]. In some African settings, misdiagnosis of chikungunya as another febrile illness, such as malaria, is common, which is concerning, given that research shows a higher burden of chikungunya in children [ 27 ].…”

“…Chikungunya cases have historically been clustered in tropical areas with warm, humid climates where the vectors thrive and cause recurring outbreaks of chikungunya fever. In a related systematic review and modelling study, we inferred subnational heterogeneity in the force of infection and transmission dynamics as well as identified both endemic and epidemic settings coexisting within countries such as Brazil, Ethiopia, and India [ 4 ]. However, the increasing spread of the vector to more geographic regions due to climate change poses a greater risk of CHIKV to more people in the future [ 5 , 6 ].…”