On July 11 2018, the Taiwan Centers for Disease Control (Taiwan CDC) announced 1 new indigenous dengue case confirmed in a student who resides in Xinzhuang District, New Taipei City. On July 7, the case developed fever, nausea, vomiting and body aches. On the next day, he sought medical attention at the emergency department and then returned home. On July 9, when he sought further medical attention after developing diarrhea, the hospital collected specimens from him for laboratory testing, and he was reported to the competent health authority as a suspected case. On July 10, infection with dengue virus type 2 was laboratory confirmed in the case. As of now, the case is hospitalized in isolation to prevent further transmission.

According to the epidemiological investigation, during the incubation period, the case did not travel overseas. The case’s primary areas of daily activities include places around his residence and his school. Prior to disease onset, during July 3 and 6, he traveled with his family members and a tour group to Tianliao District, Kaohsiung City and Taimali, Luye, and Chishang, Taitung County. During the incubation period, the case visited Xinzhuang District, New Taipei City, Tianliao District, Kaohsiung City, and several places in Taitung County. The possible source of infection is being investigated by competent health authorities. Currently, none of his contacts, including his family members residing in the same household and travelers in the same tour group, has developed suspected symptoms. The local health authorities will continue to follow up on the health of the contacts. To prevent the further spread of the disease, the local health authority has conducted epidemiological investigation around the areas where the case frequents, helped eliminate vector breeding sites around the same areas, and reinforced health education among residents in the areas.

Thus far this year, as of July 10, 2 indigenous dengue cases that respectively reside in Kaohsiung City and New Taipei City and 103 imported cases been confirmed. The numbers of imported cases confirmed during the same period in 2014 and 2018 respectively are 95, 120, 147, 124 and 103. During the recent one month, the majority of the imported cases reported in Taiwan became infected in Southeast Asian countries, including Cambodia, the Philippines, and Thailand. Recently, among the neighboring countries, the levels of dengue activity in Thailand, Cambodia, Malaysia and Sri Lanka have been on the rise, while the level of dengue activity in Laos has slightly lowered. The levels of dengue activity in other Southeast Asian countries and China have remained low.

In light of Typhoon Maria, heavy downpours are expected in northern and central Taiwan recently, which will lead to the accumulation of water containers in the environment that facilitate vector breeding. Hence, the public is urged to proactively empty and clean any potential vector breeding sites such as containers that collect standing water in and around the home after the rain in order to prevent dengue transmission. In addition, Taiwan CDC reminds travelers planning to visit areas affected by dengue fever to take precautions against mosquito bites, including wearing light-colored clothing, long sleeves and long pants, applying officially approved mosquito repellent to exposed parts of the body, staying at accommodations installed with window screens, screen doors or air conditioners.

If symptoms such as fever, headache, retroorbital pain, myalgia, arthralgia, and rash develop after their return, please seek immediate medical attention and inform the physician of their travel activity history in order to facilitate early diagnosis, case reporting and treatment. Simultaneously, healthcare facilities are urged to remain vigilant for suspected cases and report them early in order to facilitate subsequent implementation of relevant measures by the competent health authorities. For more information, please visit the Taiwan CDC website at https://www.cdc.gov.tw or call the toll-free Communicable Disease Reporting and Consultation Hotline, 1922 (or 0800-001922).