Culex quinquefasciatus (Image provided by the U.S. Centers for Disease Control and Prevention, CDC).
SEOUL, Nov. 3 (Korea Bizwire) — South Korean health authorities have confirmed the discovery of a tropical mosquito species capable of transmitting infectious diseases such as West Nile fever, marking the first verified presence of the insect in the country and heightening concerns about climate-related shifts in disease vectors.
According to the Korea Disease Control and Prevention Agency (KDCA), researchers identified Culex quinquefasciatus, commonly known as the southern house mosquito, among specimens collected in Jeju Island in August. The mosquito, typically found in tropical and subtropical climates, had not been observed in Korea in nearly seven decades.
The finding, which will soon be detailed in the KDCA’s scientific journal Health and Disease, was confirmed through genetic analysis. The agency said multiple specimens were found across Jeju, suggesting the species may already have established a breeding population.
“The exact route of entry remains unclear, but current environmental conditions in Korea are now suitable for the species to survive,” said Lee Hee-il, director of vector analysis at the KDCA. “We plan to determine next year whether it has spread to the mainland.”
Culex quinquefasciatus (Image source: O Estado de S. Paulo, Brazil)
The mosquito is a known vector for West Nile fever, a viral infection that in severe cases can lead to encephalitis or meningitis. Europe reported more than 1,400 cases and 125 deaths from the disease last year, according to the European Centre for Disease Prevention and Control.
While Korea has not recorded any domestic transmission—only a single imported case from Guinea in 2012—the KDCA emphasized that the mosquito’s discovery does not necessarily mean the risk of West Nile fever has increased. Other local mosquito species capable of carrying the virus have never tested positive for infection.
Still, experts say the emergence of new mosquito species in Korea reflects the broader effects of a warming climate. “The appearance of tropical species is a clear sign of climate change,” said entomologist Kim Heung-chul of Yu Technology Research Institute. “Jeju Island, with its higher temperatures and increasing international travel, is becoming a natural gateway for new species.”
A similar case occurred in 2023, when researchers from Seoul National University identified a forest mosquito native to Southeast Asia on Jeju Island for the first time. Average temperatures on the Korean Peninsula have risen by 1.6 degrees Celsius over the past century, according to government data—a shift scientists say is reshaping the country’s ecological landscape and expanding the range of disease-carrying insects.
M. H. Lee (mhlee@koreabizwire.com)
