Food poisoning cases among school children in Korea increased sharply last year compared to the year before mainly due to contaminated kimchi served in school meals, the Ministry of Education announced on Sunday.

Last year, 54 cases of food poisoning were reported throughout the nation, an 80 percent increase from 30 cases the year before.

Food poisoning at schools had been on a gradual decline since 2006 until last year, when 3,185 schoolchildren received hospital treatments for the illness, a record high in five years.

By month, the most school food poisoning cases occurred in September, right after the heat wave and heavy rain season end, with 1,162 children receiving hospital treatments. August followed with 267 and November with 258.

Half of the total food poisoning cases were reported from schools in Gyeonggi Province and Incheon, at 14 and 11 cases, respectively.

The ministry said kimchi contaminated by bacteria was found to be the main reason for the rise in food poisoning cases.

A total of 16 food poisoning cases related to contaminated kimchi were reported across the country with 1,201 children receiving treatment from hospitals. Only five such cases were reported the year before.

Food poisoning caused by kimchi is usually due to unsanitary washing procedures in which cabbages are rinsed with norovirus-contaminated underground water.

After another norovirus-related school food poisoning case was reported in North Jeolla Province this April, the MOE ordered that schools only accept kimchi that has received a HACCP certification, which is a system to prevent hazards in the production process.

By Kwon Bum-joon (bjkwon@heraldcorp.com)