Dengue mosquito (Image courtesy of Flickr/CCL)
SEOUL, Apr. 12 (Korea Bizwire) — The peak mosquito activity period in South Korea has arrived approximately two months earlier than usual this year, a consequence of rising temperatures driven by global warming and climate change.
As the country’s climate grows increasingly warmer and more humid, resembling a subtropical pattern, concerns are heightening over the potential spread of mosquito-borne diseases like dengue fever, commonly found in tropical regions.
On March 30, the Korea Disease Control and Prevention Agency (KDCA) issued a nationwide “Japanese Encephalitis Advisory” following the early emergence of the Culex pipiens pallens mosquito species, commonly known as the house mosquito.
This mosquito, among the most prevalent of its kind, concludes its dormancy period earlier than other species, prompting health authorities to mark its initial collection as the start of the mosquito season each year.
Typically, these mosquitoes enter an adult dormant state in mid-November as temperatures drop, before resuming active behavior in late May when temperatures rise above 13°C (55°F).
However, within the past decade, their first appearances have been advancing to late March or early April. Notably, since 2020, with the exception of 2022 (April 11), the house mosquito has consistently emerged by late March.
Experts attribute this shift to the impacts of climate change and rising temperatures. Indeed, on April 14, Seoul’s daytime high temperature is expected to soar to 27°C, continuing a pattern of above-average warmth following an unusually mild winter last year.
Most malaria patients are found in the border areas in Incheon and Gyeonggi and Gangwon provinces between May and October when mosquitoes are active. (image: Wikimedia)
“Not only mosquitoes but also pests like cicadas and crickets are emerging from dormancy earlier,” said Lee Kang-woon, director of the Holoce Ecosystem Conservation Research Institution. “As the life cycles of mosquitoes and other pests extend, their breeding frequency will increase, leading to greater potential harm.”
The earlier mosquito season has amplified concerns over the transmission of mosquito-borne viral diseases. Particularly worrisome is the possibility of dengue fever, currently spreading across North America, becoming endemic in South Korea if global warming persists.
Dengue is an acute febrile illness transmitted through the bites of mosquitoes carrying the dengue virus. Notably, the Aedes albopictus mosquito, also known as the Asian tiger mosquito, which inhabits South Korea, is among the vectors capable of transmitting the disease.
“For the dengue virus to become endemic, adult mosquitoes carrying the virus must survive until January of the following year through blood-feeding,” explained Lee Dong-kyu, a professor of environmental studies at Kosin University.
“Currently, South Korea’s average January temperature is too low for most mosquitoes to survive.” However, he cautioned, “If global warming continues and the country’s average January temperature exceeds 10°C, mosquitoes could potentially survive and establish the virus locally.”
Notably, the average January temperature on Jeju Island, a subtropical region of South Korea, already reached 7.8°C this year, inching closer to the critical 10°C threshold.
Lina Jang (linajang@koreabizwire.com)
