About five cases of Cryptosporidium and Campylobacter have been reported on the island during the past three months.
It is thought some of those affected may have been involved in helping farmers to rescue livestock after heavy snow last month.
Food Safety Manager Ivan Bratty told BBC that simple precautions must be taken.
“These recent cases serve as a timely reminder of the importance of thorough hand washing after handling livestock and before preparing or handling food to prevent infection and the spread of disease in the community,” he said.
“It is also important for anyone suffering from diarrhoea to avoid swimming pools as Cryptosporidium can survive in chlorinated water.”
Food safety is never simple.