A specialist in infectious diseases, Dr Joseph Tsang, on Tuesday reminded people to be extra cautious while handling seafood, saying two people have died after an outbreak of invasive Group B Streptococcus infections.

The Centre for Health Protection has reported eight such infections in the New Territories East Cluster over the past few months, and many of the patients had bought freshwater fish from a Sheung Shui market before falling ill.

Tsang explained that invasive Group B Streptococcus is a kind of bacterial infection, but it may be easily overlooked as people often develop flu-like symptoms. He warned the bacteria can cause sepsis and even lead to death.

The expert said the bacteria can often be found in freshwater fish – especially cultured fish – as well as many other types of seafood.

"For food handlers, if they have cut wounds over their hands and are somehow in contact with potentially contaminated food items, the infections can happen in the body by getting through the wounds," he told RTHK.

"Workers of aquatic products or restaurants must wear gloves when handling freshwater or cultured fish or aquatic products and avoid direct contact with them or dirty water with bare hands. [People should] try not to eat… sashimi, raw or undercooked freshwater aquatic products."