The Health Department recorded 122 new HIV cases in the first three months of this year, the third-highest quarterly figure since 1984, when the first case was found in Hong Kong.
It brought the total recorded number of infections of HIV - the virus that causes Aids - to 5,349.
The tally of new cases was the highest since the third quarter of 2009, when there were 123. In the same period last year, there were only 103 cases. The peak was in the third quarter of 2007, with 125 cases.
The previous quarter, the last three months of last year, saw 121 new cases.
'It is uncommon to have over 120 new cases in two consecutive quarters,' a consultant for the department's special preventive programmes, Dr Wong Ka-hing, said in announcing the figures yesterday. The average was usually about 100.
But he said one reason could be more people having tests for the virus, especially among one of the high-risk groups - men who had sex with other men.