Food poisoning refers to infective or toxic conditions due to ingestion of foods contaminated with microorganisms, chemicals and natural toxins. More specifically, it refers to the ingestion of foods contaminated with live bacteria, or their toxins, causing diarrhea, abdominal pain and acute gastro-enteric symptoms.

Approximately 80 percent of food poisoning is caused by bacteria and viruses, but other reasons include natural toxins from puffer fish, poisonous mushrooms and fungi. This is caused by inappropriate storage or reheating of foods, or due to contamination by third parties or instruments used when cooking. It is a common condition that occurs around us.

Spring is here, and this year is warmer than before, so we can expect a higher probability of food poisoning. The reason that food poisoning is common during spring is because of its lower temperature in comparison to the summer, with large temperature differences during the day. However, people are not aware of this and are less careful with food. One example is how people often store food at room temperature outside when they go camping or for picnics.

In particular, foods such as sandwiches and sushi rolls are handmade, and are more likely to be contaminated with microorganisms. The various sub-ingredients which are rich in protein and carbohydrates, along with diversity of cooking temperature and water content create an ideal condition for microorganisms to grow in.

Hence, you should avoid foods such as sushi rolls and sandwiches if you move long distances, as they are prone to going stale. If you are making sushi rolls, make sure all the ingredients are cooled and the food is stored in a cool place. When making sandwiches, all vegetables should be washed in running, clean water, and should be dried before putting in between bread. Avoid storing food in the car boot as it can heat up quickly, and use ice containers or store in other cool areas.

People tend to avoid seafood in the summer due to food poisoning risks. They believe that the risk of food poisoning is lower in autumn and spring and like to eat seafood more in these seasons.

However, the recent rising climate and the sea temperature have led to increased risk of food poisoning from seafood in spring. Popular seafood in spring includes squids and crabs, but these can contain E.coli and vibrio species in seawater that can cause food poisoning.

For safe consumption, clean all the ingredients, wash your hands well, and cook the seafood properly. Make sure to use different knives and chopping boards that are clean when cooking, to avoid transfer of contaminants.

Fresh vegetables and herbs in spring are good for you, and are popular among herb collectors.

However, some native plants that are found in hills and mountains are sometimes mistaken for edible herbs. Other herbs such as ferns, dereup, wild chives and day lilies have toxicity, and cooking these improperly, or eating nonedible parts of these plants can cause various problems. To avoid food poisoning from herbs, make sure that they are edible. When eating them uncooked, wash at least 3 times in clean tap water, to remove contaminants, microorganisms and pest control chemicals. Herbs such as ferns, wild chives, day lilies and dereup are slightly toxic, so should be cooked in boiling water before consumption to remove the toxins. Day lilies contain colchicine in their leaves, so improper cooking may lead to fever, nausea, vomiting, abdominal pain, headache and renal failure. It becomes more toxic as the plant grows, so only the youngest plants should be consumed. They should be cooked in boiling water and soaked in cold water for at least 2 hours before consumption.

Avoiding food poisoning in spring

1. Wash your hands during cooking and before eating food.

2. Only prepare enough food for a meal and eat the food immediately.

3. Store hot and cold foods separately.

4. Cool foods completely before storing in the lunch box.

5. Store your lunch in a cooling box to lower the storage temperature.

6. Check that the herbs you have collected are edible and make sure they are cooked the right way.

7. Use different knives and chopping boards when preparing foods to prevent cross-contamination.

By Ha Young-eun

The author is a doctor who practices at the Samsung Medical Center in Seoul. ― Ed.