By Yun Suh-young
A recent report shows the Japanese encephalitis virus, which has a fatality rate of 20 to 30 percent if caught, is active across the nation.
The number of mosquitoes spreading the virus has increased greatly this year, requiring travelers to be cautioned about the risk.
The Korea Centers for Disease Control and Prevention said the number of the virus-carrying mosquitoes collected until July this year was 2.4 times that of those collected last year.
As the number of mosquitoes has increased considerably, the center advised people to reduce outdoor activities between 10 p.m. and 4 a.m. when mosquitoes are most active and to wear long-sleeved shirts and pants.
According to a 2011 report by the Korea National Institute of Health, 23.8 percent of pigs’ serum samples showed a positive antibody reaction to the virus. The surveyed regions were South and North Chungcheong, Jeolla, Gyeongsang and Gangwon Provinces.
The percentage of positive reactions was 32.1 and 23.3 percent for North and South Chungcheong respectively.
The rate was 9.8 and 29.3 percent for each of North and South Jeolla, 34.4 and 30.6 percent for North and South Gyeongsang, 23.3 percent for Jeju and 2.5 percent for Gangwon Province.
The results, although differing in numbers, show that the virus was active in almost all parts of the nation except Seoul and Gyeonggi Province.
When a pig acquires the virus, it acts as an amplification host by increasing the strength of the virus within its body.
In Busan, the virus was found in the bodies of mosquitoes collected twice last September. In Masan, Jeju, and Tongyong regions, a new type of Flavivirus, which Japanese encephalitis belongs to, was detected in the mosquitoes.
Last year, three people were diagnosed with Japanese encephalitis out of the 540 cases examined. One was an incoming foreigner from Thailand and the other two were from South Chungcheong Province.