Molecular surveillance of arboviruses circulation and co-infection during a large chikungunya virus outbreak in Thailand, October 2018 to February 2020

Abstract

A large national outbreak of chikungunya virus (CHIKV) was recently reported in Thailand. While dengue virus (DENV) infection tends to occur year-round with an upsurge in the rainy season, Zika virus (ZIKV) also circulates in the country. The overlap in the distribution of these viruses increased the probability of co-infections during the heightened CHIKV activity. By examining 1806 patient serum samples submitted for CHIKV diagnostics from October 2018-February 2020 (511 CHIKV-negatives and 1295 CHIKV-positives), we used real-time reverse transcription-polymerase chain reaction to identify DENV and ZIKV individually. A total of 29 ZIKV and 36 DENV single-infections were identified. Interestingly, 13 co-infection cases were observed, of which 8 were CHIKV/DENV, 3 were CHIKV/ZIKV, and 2 were DENV/ZIKV. There were six DENV genotypes (13 DENV-1 genotype I, 10 DENV-2 Asian I, 10 DENV-2 Cosmopolitan, 6 DENV-3 genotype I, 2 DENV-3 genotype III, and 5 DENV-4 genotype I). Additionally, ZIKV strains identified in this study either clustered with strains previously circulating in Thailand and Singapore, or with strains previously reported in China, French Polynesia, and the Americas. Our findings reveal the co-infection and genetic diversity patterns of mosquito-borne viruses circulating in Thailand.

Understanding the resurgence of chikungunya virus during 2020−2021 in Pune, India, based on genomic analyses: A seven year study

“…The female gender was associated with a higher risk of symptomatic chikungunya. Similar results were observed during outbreaks in India and Thailand 3,13 . It is possible that sex hormones might modulate the inflammatory response, contributing to the development of symptomatic disease 14 .…”

“…Age above 30 has been reported to be associated with symptomatic chikungunya 3 . A study from Thailand has shown that higher age was associated with the presence of joint pain in CHIKV‐infected subjects 13 . The female gender was associated with a higher risk of symptomatic chikungunya.…”

“…3 A study from Thailand has shown that higher age was associated with the presence of joint pain in CHIKV-infected subjects. 13 The female gender was associated with a higher risk of symptomatic chikungunya. Similar results were observed during outbreaks in India and Thailand.…”

“…Similar results were observed during outbreaks in India and Thailand. 3,13 It is possible that sex hormones might modulate the inflammatory response, contributing to the development of symptomatic disease. 14 The peak number of cases was observed during the 35 th week, which coincided with the rainy season in Pune.…”

Molecular identification and phylogenetic analysis of chikungunya virus among dengue-negative patients in Kolkata, India

“…In 2006, Kolkata, West Bengal, India, experienced a CHIKV out-break. Even though a few occasional cases of CHIKV infection were investigated from a few Indian states between 2010 and 2015 [ 3 ], the rate of infection has been declining until a 2016 outbreak in the capital city Delhi [ 4 ]. Currently, the disease has spread throughout the entire nation and outbreaks cause significant economic and productivity losses.…”