Mosquitoes carrying malaria, dengue fever appearing 2 weeks earlier than usual in Seoul

Mosquitoes that transmit infectious diseases such as malaria and dengue fever are appearing earlier than usual this year, prompting health authorities to urge heightened vigilance.

The Seoul Metropolitan Government's Institute of Public Health and Environment said Thursday that it has been collecting and testing mosquitoes across Seoul since March 30, finding that malaria-carrying mosquitoes were caught about two weeks earlier than the seasonal average, while mosquitoes that transmit overseas-imported diseases such as dengue fever appeared about one week ahead of schedule.

However, no malaria or dengue fever pathogens were detected in the collected mosquitoes.

The overall mosquito population was similar to average levels, but the earlier emergence of disease-carrying species was flagged as a concern.

Earlier, a Japanese encephalitis alert was issued nationwide on June 17, followed by a malaria caution advisory on June 22.

With disease-carrying mosquitoes confirmed in Seoul in quick succession, quarantine authorities have been strengthening their surveillance systems.

The institute said that given the increase in mosquito-borne infections in Seoul last year — when disease-carrying mosquitoes also appeared early — continuous monitoring and preemptive control measures are necessary.

The institute said it will continue surveillance of disease-carrying mosquitoes and pathogen testing, and will immediately share any abnormal findings with relevant agencies to mount a rapid response.

The institute urged residents to eliminate standing water around their homes — including in flowerpots and empty containers — control larvae in septic tanks and drainage sumps, and regularly inspect window screens. When outdoors, people should follow personal protection guidelines such as wearing long sleeves and pants and using insect repellent.

Anyone who develops symptoms such as chills or high fever after visiting a malaria-risk area should seek medical attention at a clinic or public health center immediately. Those who completed military service in a malaria-risk area within the past two years are eligible for free testing at a nearby public health center even if they have no symptoms.