The Centre for Health Protection confirmed a second imported measles case on Wednesday, the mother of a patient announced a day earlier.
The 22-year-old woman developed a fever on December 18. As her son had tested positive, she was identified through contact tracing and admitted to hospital. She tested positive and is in stable condition at Princess Margaret Hospital.
She had been outside Hong Kong from October 1 to December 16 and had not been vaccinated. The case is classified as imported.
As both patients visited a private clinic on December 19, the centre is contacting others who were there. No high-risk individuals have been identified so far.
Controller Edwin Tsui urged non-immune travelers to ensure they have two measles vaccine doses before trips to affected areas, citing ongoing outbreaks in North America, Europe, Southeast Asia, Japan and Australia.
He said local vaccination coverage remains above 95 percent but some groups, including non-local-born residents and children under one, remain at risk from imported cases.
