A South Korean traveler returning home from an overseas trip was found to have contracted cholera, local health authorities said Monday, the country\'s first case of the disease this year.The unidentified patient, who recently visited Delhi and Varanasi in India, showed symptoms of the disease, like diarrhea, upon arrival at Incheon International Airport, the Korea Centers for Disease Control and Prevention (KCDC) said.In a detailed checkup, the person tested positive for the V. cholerae 01, Ogawa virus, it said.The KCDC said it has acquired a list of 10 other people who traveled with the cholera patient to check if they had caught the disease as well.It stressed that people traveling to India and Southeast Asian countries during the summer months should be on guard against the disease.Cholera is caused by the consumption of bad water or food and leads to rapid dehydration through diarrhea and vomiting. In serious cases, and if no medical treatment is given, it can lead to shock and death, with small children being particularly vulnerable.Health authorities have advised travelers to take keen interest in personal hygiene by washing their hands, boiling drinking water and avoiding raw fish and uncooked foods.