CAMP RED CLOUD, South Korea — Mosquitoes carrying malaria are far more prevalent in South Korea now than they were at the same time last year because of unusually warm autumn weather, national public health officials said Tuesday.
Workers from the Seoul Research Institute of Public Health and Environment collected 75 mosquitoes carrying malaria from September through the second week of October. Collections in the same area and time last year yielded only 10 malaria-carrying mosquitoes.
“The relatively high temperature of the metropolitan area makes it more susceptible to mosquito breeding,” said Kweon Jun-wook, director of communicable disease surveillance at the Korea Centers for Disease Control and Prevention.
But the bite risk by a female Anopheles sinensis, the only type of mosquito that transmits malaria, is highest north of Seoul, said Kweon and Dr. Terry Klein, a recently retired Army colonel who is now the U.S. military’s regional emerging infectious disease consultant.
Although temperatures have dipped this week, mosquitoes will be around until the country experiences its first frost, Klein said.
Most mosquitoes that people see here, especially in urban environments, are the common brown mosquito. They pose no threat of disease, Klein said.
“At the end of the season every year, mosquitoes inside the house are more abundant,” Klein said. “They are searching for a warm place to rest.”
Despite the Seoul public health institute’s findings, U.S. servicemembers have been lucky. No one has reported a case of malaria on a U.S. installation within the past few weeks, Klein said.
However, the risk remains, especially for Area I troops.
There are two forms of parasitic malaria strains found in South Korea. One finds its way out of the liver within 12 to 20 days; the other lays dormant for six to nine months before causing symptoms, Klein said.
Malaria’s symptoms can mimic more common illnesses, Klein said. Fever, chills and other symptoms may subside after a day or two but reappear after a few days.
It’s critical for people with such symptoms to tell their doctor where they have been within the last year, Klein said. For example, one military patient diagnosed with malaria last month probably contracted it while in Honduras, Klein said.
People can reduce their exposure to malaria and mosquitoes by wearing long sleeves and pants, especially at dusk; by removing any standing water, which acts as a mosquito breeding ground; and by using mosquito repellent with a 33 percent concentration of DEET.
Hwang Hae-rym contributed to this report.
Another illness risk
Hantavirus also is a potential danger to servicemembers training in Area I, said Dr. Terry Klein, the U.S. military’s regional emerging infectious disease consultant. Four cases have been reported among the military community this year, he said.
It’s transmitted in dusty areas where rodents are located, and has a 10 percent mortality rate, Klein said. People can contract the virus from contact with the rodents or their waste, according to the U.S. Centers for Disease Control and Prevention.
Hantavirus can cause Hantavirus pulmonary syndrome, in which the lungs fill with fluid, possibly leading to respiratory failure. Symptoms include fatigue, a high fever and muscle aches.
— Erik Slavin