Introduction:Chikungunya virus(CHIKV),an arthropod-borne alphavirus transmitted by Aedes aegypti and Aedes albopictus,causes fever,severe joint pain,and rash.By 2025,it has triggered outbreaks in 119 countries,endange...Introduction:Chikungunya virus(CHIKV),an arthropod-borne alphavirus transmitted by Aedes aegypti and Aedes albopictus,causes fever,severe joint pain,and rash.By 2025,it has triggered outbreaks in 119 countries,endangering 5.5 million people.Recent epidemics in Foshan,China,have strained healthcare systems,underscoring the need to characterize viral load dynamics across infection phases.Methods:We collected 1,156 clinical samples from four Foshan hospitals in July 2025,spanning 6 days before to 12 days after symptom onset.Specimens included serum(904 valid),saliva(22),urine(4),throat swabs(3),and stool(37).CHIKV RNA was quantified via qRT-PCR;timepoints and specimen types with insufficient samples were excluded.Results:Serum showed the highest positivity(90%),followed by saliva(68%),throat swabs(15%),and urine(11%);stool was negative(0%).Serum also had the highest viral loads,confirming its optimal utility.Viral RNA was detectable as early as 1 day presymptom onset(day-1).Days 0–7 post-onset marked explosive replication and elevated loads,representing the optimal sampling window.From Day 8 onward,loads declined,requiring IgG testing to avoid false negatives.Conclusions:Serum is the gold standard for acute CHIKV diagnosis,with superior positivity and viral loads.Pre-symptomatic viral shedding(day-1)supports enhanced port-of-entry screening to intercept imported cases.Days 0–7 post-onset is the optimal sampling window for acute infection.During clearance(day 8+),IgG testing complements molecular diagnostics to reduce gaps.These findings inform evidence-based diagnosis,outbreak control,and resource allocation.展开更多
基金Supported by the Guangdong Provincial Center for Disease Control and Prevention Supports Talent Projects(0720240122)the Guangdong Provincial Key Laboratory of Pathogen Detection for Emerging Infectious Disease Response(2023B1212010010).
文摘Introduction:Chikungunya virus(CHIKV),an arthropod-borne alphavirus transmitted by Aedes aegypti and Aedes albopictus,causes fever,severe joint pain,and rash.By 2025,it has triggered outbreaks in 119 countries,endangering 5.5 million people.Recent epidemics in Foshan,China,have strained healthcare systems,underscoring the need to characterize viral load dynamics across infection phases.Methods:We collected 1,156 clinical samples from four Foshan hospitals in July 2025,spanning 6 days before to 12 days after symptom onset.Specimens included serum(904 valid),saliva(22),urine(4),throat swabs(3),and stool(37).CHIKV RNA was quantified via qRT-PCR;timepoints and specimen types with insufficient samples were excluded.Results:Serum showed the highest positivity(90%),followed by saliva(68%),throat swabs(15%),and urine(11%);stool was negative(0%).Serum also had the highest viral loads,confirming its optimal utility.Viral RNA was detectable as early as 1 day presymptom onset(day-1).Days 0–7 post-onset marked explosive replication and elevated loads,representing the optimal sampling window.From Day 8 onward,loads declined,requiring IgG testing to avoid false negatives.Conclusions:Serum is the gold standard for acute CHIKV diagnosis,with superior positivity and viral loads.Pre-symptomatic viral shedding(day-1)supports enhanced port-of-entry screening to intercept imported cases.Days 0–7 post-onset is the optimal sampling window for acute infection.During clearance(day 8+),IgG testing complements molecular diagnostics to reduce gaps.These findings inform evidence-based diagnosis,outbreak control,and resource allocation.
