Hong Kong's Centre for Health Protection said on August 18, 2026, that it was investigating a measles case involving a 35-year-old woman who developed fever and cough from August 4 and a rash on August 9, when she attended United Christian Hospital's accident and emergency department. She did not require hospitalisation and was in a stable condition; a clinical specimen tested positive for the measles virus.

The CHP said the patient was not born in Hong Kong and was unsure whether she had been vaccinated in her birthplace. She took a short outbound trip during the incubation period and did not need to work during the communicable period from August 5 to 13. Her household contacts are asymptomatic. As of 3pm on August 18, 198 people had been identified as close contacts and placed under medical surveillance; all were asymptomatic so far.

The CHP described the case as the ninth measles case recorded in Hong Kong so far this year, noting that the previous six were imported or epidemiologically linked to imported cases, with two other local cases. It said 10 cases were recorded in each of 2024 and 2025, and that two-dose coverage under the Childhood Immunisation Programme has stayed above 95 per cent while measles outbreaks persist in parts of North America, Europe, Asia and Australia.