Demand for fish at supermarkets has fallen, following a nationwide ban on the sale of raw freshwater fish earlier this month.
As well as freshwater types like song and toman - linked to a recent outbreak of Group B Streptococcus (GBS) infections this year - sales of saltwater fish and ready-to-eat sushi and sashimi have also taken a hit.
On Dec 5, the National Environment Agency (NEA) banned food establishments from using freshwater fish for ready-to-eat raw fish dishes.
Food stalls, which include hawker centres, coffee shops, canteens and food courts, as well as caterers were also ordered to stop the sale of all raw saltwater fish until they can show they know how to properly handle the meat.
Restaurants can continue to sell raw saltwater fish, such as salmon.
At Cold Storage, sales of saltwater fish have fallen by 10 per cent since the ban came into effect. Takings for freshwater fish, sushi and sashimi have dropped 20 per cent.
At FairPrice, sales of freshwater fish have decreased by 10 per cent, while demand for sashimi and sushi is down by about 15 per cent.
A FairPrice spokesman assured consumers that seafood sold at its ready-to-eat counters is "sashimi-grade" seafood, sourced from reputable suppliers licensed by Agri-Food and Veterinary Authority of Singapore.
Meanwhile, sales of toman and song fish at Sheng Siong is down by about 5 per cent from this time last year. For the song fish, the main reason for the drop was a less consistent supply this year, according to a spokesman.
Mr Lee Boon Cheow, president of the Singapore Fish Merchants' General Association, estimates that less than 1 per cent of fish sold at the fishery ports here are song and toman.
The ban came after the Health Ministry was notified of about 360 GBS infections this year, with two fatalities. About 150 were linked to the consumption of raw freshwater fish and involved an aggressive strain known as Type III GBS Sequence Type 283 (ST283).
Dr Hsu Li Yang, the director of the Singapore Infectious Diseases Initiative, supports the NEA's indefinite ban on freshwater fish.
"From a public health perspective, the ban should last until scientific advances can easily detect and/or eliminate the pathogens present in raw freshwater fish, or until some entrepreneur figures out how to farm freshwater fish that are consistently safe for raw consumption," he said.
While the source of the ST283 GBS strain is still unknown, Dr Hsu said that the strain of bacteria could have been infecting freshwater fish in Asia for a number of years. "We can speculate that environmental conditions at the fish farms changed, or something else caused the strain to spread more rapidly," he said, highlighting the need for a more thorough investigation.
While he believes it is unlikely that the strain can be completely eradicated, the ban is likely the best way to prevent future cases of ST283 GBS infections, he said.
"Hong Kong had banned the consumption of freshwater fish for more than 30 years, yet they still have sporadic human ST283 GBS infections," he said. "But we don't really need to eradicate the bacteria. We just need to eliminate or at least minimise the risk of human infection. "
Consumers like admin executive Mary Peh have stopped buying freshwater fish altogether.
"I used to buy toman fish for cooking quite often but since the ban I have switched to purchasing saltwater fish like snapper," said Mrs Peh, 63. "I also asked my children to avoid eating sashimi, just in case."
This article was first published on December 27, 2015. Get a copy of The Straits Times or go to straitstimes.com for more stories.