Hong Kong health officials investigating a confirmed case of dengue fever (DF) and to date haven’t ruled out whether the case was acquired in the city.

Aedes aegypti/CDC
Aedes aegypti/CDC

The female patient, aged 59 with good past health, has developed fever, headache and rash since September 9 and attended the Accident & Emergency Department of United Christian Hospital (UCH) on September 15 while hospitalization was not required. She had follow-up consultation at UCH again the next day and has been in stable condition.

Her serum specimen tested positive for dengue virus NS1 antigen and immunoglobulin M (IgM) antibodies to dengue virus upon testing by the Centre for Health Protection’s (CHP) Public Health Laboratory Services Branch.

“Although the patient traveled to Huizhou, Guangdong (GD), during the incubation period, according to the GD Provincial Center for Disease Control and Prevention (GDCDC), to date, local DF cases have not been reported in Huizhou. The possibility of a locally acquired infection in Hong Kong cannot be ruled out at this stage. As a precautionary measure, we are working closely with the Food and Environmental Hygiene Department (FEHD) to assess and prevent any possible spread, while GDCDC will enhance surveillance of DF,” a spokesman for the CHP said.

From September 11 to 17, three additional confirmed cases were recorded. Two were imported cases in which patients had traveled to India (one case) and Thailand (one case) during the incubation period.

As of September 17, a total of 77 cases had been confirmed this year, comprising a local case, 75 imported cases and the one case still under investigation. Of note, the number of cases recorded so far in 2015 is relatively high compared with the corresponding period in the last 10 years (from 17 to 79 from 2005 to 2014).