No Vaccines or Treatments... Increase in Mosquito-Borne Disease Cases as Overseas Travel Rises

Dengue Fever, Zika Virus, and Chikungunya Cases Increase... Beware of Mosquitoes When Visiting Southeast Asia
If High Fever, Headache, or Muscle Pain Occur After Visiting Risk Areas, Seek Medical Attention Immediately

A quarantine officer wearing protective clothing is spraying disinfectant to prevent the spread of dengue fever in San Juan City, Metro Manila, the capital region of the Philippines. Photo by Yonhap News

[Asia Economy Intern Reporter Lee Gyehwa] As COVID-19 entry restrictions have eased and overseas travel has increased, the number of patients infected with dengue fever after visiting Southeast Asian countries such as Vietnam, the Philippines, and Thailand has also risen.

Dengue fever is a disease that infects more than 100 million people annually in over 100 countries. According to the World Health Organization (WHO), the number of dengue fever cases worldwide has increased more than eightfold over the past 20 years due to the activation of international exchanges. As of September 2022, the number of cases by major countries were: Vietnam 224,771, the Philippines 160,956, Indonesia 94,355, and Thailand 19,484.

According to the Korea Disease Control and Prevention Agency on the 7th, the number of imported cases of mosquito-borne infectious diseases such as dengue fever, chikungunya, and Zika virus has increased this year. So far this year, 61 dengue fever cases have been reported. All were imported cases, mostly from Southeast Asia. Before COVID-19, there were 100 to 300 dengue fever cases annually, but the numbers dropped to 42 in 2020 and 3 in 2021 due to COVID-19 restrictions. However, as entry restrictions have been fully lifted recently, overseas visitors have increased, and with a surge of dengue fever cases in Southeast Asian countries such as Vietnam, the Philippines, and Singapore, domestic cases have also risen.

There have also been 5 imported cases of chikungunya fever, another mosquito-borne infectious disease, this year. Domestic chikungunya fever cases were first reported in 2013 with 2 cases, increased to 16 in 2019, then decreased to 1 in 2020 and 0 in 2021. For Zika virus infection, which had 3 imported cases in 2018 and 2019 respectively, 2 cases have occurred this year. Except for one domestic laboratory infection in 2020, these are the first imported cases in three years.

Dengue fever is a febrile illness transmitted by forest mosquitoes infected with the dengue virus. After an incubation period of 3 to 14 days, symptoms such as high fever, headache, and muscle pain suddenly appear. Red spots may also develop over the body. About 5% of infected individuals may develop dengue hemorrhagic fever, which causes bleeding in multiple parts of the body, or dengue shock syndrome, which leads to bleeding and a drop in blood pressure, potentially resulting in death.

Dengue fever has no preventive vaccine or specific treatment. To alleviate dehydration and high fever symptoms, fluid replacement is provided, antipyretics and pain relievers are prescribed, and blood transfusions are performed if bleeding continues. With appropriate treatment in the early stages of infection, most patients recover within about a week. However, if treatment is delayed, the fatality rate of dengue fever can rise up to 20%. If symptoms such as high fever, headache, and rash appear after being bitten by mosquitoes in risk areas, immediate medical consultation is necessary.

To prevent dengue fever, the first step is to avoid mosquito bites. Before visiting risk areas such as Southeast Asia, it is advisable to check the infectious disease information specific to the destination on the Korea Disease Control and Prevention Agency website (kdca.go.kr) and prepare mosquito repellents, mosquito nets, mosquito coils, and basic medicines.

During the visit, avoid grassy areas and forests where mosquitoes are abundant as much as possible. Use mosquito repellent when going outdoors. Mosquitoes are attracted to dark colors, so wear light-colored long-sleeved shirts and long pants whenever possible. Stay in accommodations with window screens, mosquito nets, and good air conditioning.

If fever, headache, muscle pain, joint pain, rash, or other symptoms occur within two weeks after returning to Korea, visit a nearby medical institution immediately for diagnosis. At that time, inform the medical staff of your recent overseas travel history.

This content was produced with the assistance of AI translation services.