Detection of DENV in Aedes albopictus during the 2024 sporadic dengue outbreak in Wuhan city, Hubei Province, China

From September to October 2024 in Wuhan, three indigenous dengue cases were reported in Wuhan for the first time since the 1940s. Here, we report the results of the epidemiological investigation of the sporadic dengue outbreak and the detection of dengue virus (DENV) in Aedes (Stegomyia) albopictus (Skuse) (Diptera: Culicidae) collected from locations surrounding the living and working places of patients. A total of 190 female and 56 male Ae. albopictus mosquitoes were collected using a combination of BG-Mosquitaire trap and human-baited double net (HDN) trap during the outbreak response. DENV RNA was detected via RT-PCR in patient serum and mosquito samples. Among the Aedes mosquitoes tested, DENV-1 RNA was detected in two samples, with an average MIR of 10.5, but only one of which achieved the DENV sequence. Phylogenetic analysis showed that the virus strain detected in the mosquito sample, sharing 100% homology with that in the patient serum sample, belonged to genotype 1IK.2 and was closely related to strains circulating in Guangzhou in 2023. This is the first report of the detection of DENV in Ae. albopictus during a sporadic autochthonous dengue sporadic outbreak in Wuhan.