Risk factors for symptomatic and asymptomatic chikungunya infection

Abstract

Transmission was determined by environmental conditions whereas symptoms were associated with personal biological factors and social setting.

Global protein profiling studies of chikungunya virus infection identify different proteins but common biological processes

“…Previous studies in Italy and Malaysia have suggested that less than 20% of CHIKV infections of humans are asymptomatic, although studies in Mayotte Island and Thailand report higher figures of approximately 28% and 47% asymptomatic cases, respectively. The low numbers of asymptomatic cases of infection are in stark contrast to mosquito‐transmitted flaviviruses such as dengue virus and Japanese encephalitis virus with asymptomatic : symptomatic ratios in the order of 3:1 for dengue and 25–1000:1 for Japanese encephalitis .…”

Risk of transfusion‐transmitted chikungunya infection and efficacy of blood safety implementation measures: experience from the 2009 epidemic in Songkhla Province, Thailand

“…Whether the implementation measures based on CHIKF‐related symptoms observation or the other invention strategies (i.e., screening for CHIKV RNA alone, predonation screening for donors at risk alone, or in combination with either clinical symptoms observation or screening for CHIKV RNA) could be applied in another outbreak with a different proportion of asymptomatic cases was questionable. Therefore, this study compared further the potential impact of implementing various intervention strategies on transfusion risk reduction at the various prevalences of asymptomatic CHIKV infection rates (3% to 47%) …”

“… The estimates were based on data obtained from Week 13 to Week 43 (April to October) of the 2009 epidemic period when the proportion of asymptomatic CHIKV‐infected individuals varied from 3% to 47% …”

“…These additional strategies were as follows: 1) a CHIKV RNA screening test–based strategy; 2) predonation screening for donors at risk alone; and 3) a combination of predonation screening for donors at risk and subsequent screening for CHIKV RNA or clinical observation in donors at risk, together with an up to 7‐day quarantine of blood components before releasing the blood. Herein, all of the efficacies of blood safety measure–based strategies were calculated at the various prevalences of asymptomatic infection rates that varied from 3% to 47% that were cited in the literature, with a compliance rate of 100.0%.…”

Zika Virus Emergence and Expansion: Lessons Learned from Dengue and Chikungunya May Not Provide All the Answers

“…26 CHIKV was thought to have a higher presentation rate compared with DENV, but recent reports have estimated as much as 47% of infections are asymptomatic. 27 ZIKV asymptomatic rates were estimated to be relatively high during the Yap Island outbreak, 9 though in subsequent outbreaks these were not reported. Until there is comprehensive knowledge of asymptomatic rates-not only the prevalence of, but also mechanisms behind them-assessments of total transmission will be underestimates.…”