Chikungunya will establish autochthonous transmission in at least one subtropical East Asian city outside Guangdong Province (e.g., Taiwan, South Korea, or Japan) during the 2026 or 2027 vector season, based on the documented 2025 Guangzhou urban epidemic demonstrating CHIK transmission competence in a temperate-subtropical East Asian megacity.

System-generated assessment. This assessment remains under review until the stated horizon or until sufficient evidence allows evaluation.

Moderate confidence

Confidence in this assessment

40%

The evidence is meaningful, but there is still material uncertainty. Based on 10 linked evidence items and assessed against 180D.

Assessed through 180D10 linked evidence itemsTracking since Apr 14, 2026

How this assessment will be evaluated

The criteria the system uses to determine whether this assessment is borne out by the stated horizon.

Automated

Method

Evidence Match

The condition the system checks for when evaluating this assessment.

Minimum source quality

T1Primary Institutional

Evidence must meet or exceed this credibility tier to count toward evaluation.

Required terms

temperate-subtropicalautochthonousdemonstratingtransmission

Evidence quality mix

Tracking since Apr 14, 2026.

T210

Integrity referencesCryptographic hashes for verification

Registration

Integrity anchor

Brier 0.202

19 resolved novel pathogen detection predictions.

Scope synthesis

The current analyst narrative for this scope.

Open synthesis →

Hong Kong reports first locally acquired dengue case of 2026; Guangzhou chikungunya epidemic-size study confirms massive underreported 2025 burden; multi-regional CHIK escalation signal strengthening.

Evidence linked to this assessment

10 linked items.

Chikungunya - La Réunion and Mayotte. Although chikungunya outbreaks and endemic transmission oc

Currently interpreted as supporting evidence for 9 tracked assessments.

T2https://www.who.int/emergencies/disease-outbreak-news/item/2025-DON567supports

Apr 13, 2026

Estimating the epidemic size of chikungunya virus infection in Guangzhou, China, from July to Se

Currently interpreted as supporting evidence for 6 tracked assessments.

T2https://pubmed.ncbi.nlm.nih.gov/41911367/