The Centre for Health Protection has reminded people to maintain strict personal, food and environmental hygiene due to an upsurge in Hepatitis A cases.
As of yesterday, 33 cases had been recorded this year compared to 12 cases each in the first quarters of 2012 to 2014.
Last month, 20 cases were recorded - the highest monthly number since April 2004.
There were a total of 43 cases in 2012; 44 in 2013; and 46 last year.
The 33 cases this year involve 16 men and 17 women aged 11 to 66. All were sporadic, with patients living in various districts across the city. All are now in stable condition.
The infection is caused by the Hepatitis A virus, causing inflammation of the liver cells. Most patients make a complete recovery.
The incubation period is generally long, lasting around four weeks, but can last as long as 50 days. The centre is investigating whether this year's cases were epidemiologically linked.
The Hepatitis A virus is usually transmitted by a faecal-oral route either through contaminated drinks or food, or directly from person to person.
The centre reminded people to wash their hands frequently, cook food thoroughly and avoid high-risk foods like shellfish, raw food or half-cooked food.
