SINGAPORE: The Health Ministry has said it found no links between sashimi - which is usually made using saltwater fish, and Group B streptococcus (GBS) infections.
This has led to some people making the assumption that raw saltwater fish could be safe, but a former Director of Food Safety, Zoonosis, and Food-borne Diseases at the World Health Organization has cautioned that saltwater fish is just as likely to carry the disease as freshwater fish.
"These types of bacteria are found in many different animals - both mammals on land, including humans, and also mammals in the sea, and fish in seawater and fish in freshwater. It's not really correct to say that it's only related to freshwater fish,” said Professor Jorgen Schlundt from Nanyang Technological University’s School of Chemical and Biomedical Engineering.
The professor said bacteria could be introduced if fish is not handled hygienically during transportation, or if the fish are kept under high temperature.
Farming methods could also be another factor, he said. For example, fish that are kept in small spaces should not be consumed raw.
He said: "If you're trying to put pressure on your production system by putting lots of fish in there, then you can create these problems. If the water is not clean enough, you can also create these problems. But we have to remind ourselves that these bacteria are out there, all the time, that basically it's not something totally new, and that this only happens in Singapore. These bacteria are out there - it's been documented in China, in a number of other countries also."
The National Healthcare Group said those at higher risk of infection include younger children, pregnant women and people with weakened immune systems. It added that symptoms of infection include blood poisoning, pneumonia, severe headaches and stiff necks (meningitis).