Kuala Lampur, May 26 -- When news emerged of a norovirus outbreak aboard the Caribbean Princess cruise ship recently, many Malaysians may not have paid much attention to it. Stomach bugs during travel are often assumed to be routine food poisoning or a minor inconvenience that passes after a day or two.

But the outbreak, which affected more than 100 passengers and crew members, serves as a useful reminder that not all gastrointestinal infections behave the same way, and not all can be prevented using the habits many of us became accustomed to during the Covid-19 pandemic.

Norovirus, sometimes referred to as the "vomiting bug", is highly contagious and spreads very quickly in crowded environments such as cruise ships, hotels, schools, ho...