The Hong Kong Centre for Health Protection (CHP) of the Department of Health (DH) is today (July 16) investigating a suspected local case of dengue fever (DF), and hence again urged the public to maintain strict environmental hygiene, mosquito control and personal protective measures both locally and during travel.

Aedes aegypti/CDC
Aedes aegypti/CDC

“The patient had no recent travel history and the infection might be locally acquired. While pending laboratory confirmation, as a precautionary measure, we are working closely with the Food and Environmental Hygiene Department (FEHD) to assess and prevent any possible spread,” a spokesman for the CHP said.

The patient is a 47-year-old woman with good past health. She has presented with fever, headache, myalgia and mild joint pain since July 10. She attended the Accident and Emergency Department of North Lantau Hospital on the same day and was subsequently transferred to Princess Margaret Hospital for treatment. She was discharged on July 15.

As her blood sample tested positive for immunoglobulin M (IgM) antibodies to dengue virus but negative for dengue virus antigen and nucleic acid upon testing by the CHP’s Public Health Laboratory Services Branch today, this case is now classified as a suspected case.

Initial inquiries revealed that the patient lived and worked in Lotus Pond Temple of Lantau Island. She recalled mosquito bites near the temple and mainly stayed around the temple during the incubation period. She had no travel history within the incubation period.

The patient’s household contacts have remained asymptomatic so far and have been put under medical surveillance.

“Upon notification, the CHP immediately commenced epidemiological investigations and promptly informed the FEHD for vector investigation and mosquito control. The CHP’s investigations and health education in the vicinity where the patient frequented are proceeding,” the spokesman said.

To date, 52 DF cases have been confirmed this year including one local and 51 imported cases. In 2014, there were three local and 109 imported cases. In 2013, 103 cases were filed and all were imported.