The number of cases of norovirus infection has surged, reaching the highest level in five years.

In addition, various respiratory infections, including respiratory syncytial virus (RSV), have broken out, prompting the health authorities to rush to activate the emergency quarantine system.

The Korea Disease Control and Prevention Agency (KDCA) said Friday that the number of patients with norovirus infection reached 360 in the second month of January, the highest number in the past five years, based on hospital-level enteric infection surveillance.

The number of people with norovirus infection increased by more than 150 over the past month. More specifically, the number of patients increased from 201 in the second month of December to 214 in the third month of December, 279 in the fourth month of December, 340 in the first week of January, and 360 in the second month of January.

The KDCA said that the peak of the previous norovirus outbreak was between the third week of January and the fourth week of February.

"The outbreak is likely to continue for some time. Infants and children aged 0 to six years old account for about 50 percent of the cases, so it is necessary to remain vigilant in daycare centers and kindergartens," it said

The number of hospitalized patients with RSV is also on the rise.

The number of hospitalized RSV cases in 218 hospital-level settings under surveillance increased from 368 in the third week of December to 467 in the fourth week of December, 421 in the first week of January, and 461 in the second week of January. Infants and children aged 0-6 years also accounted for 57.7 percent of the total RSV cases.

In response, the KDCA has decided to accelerate the implementation of the emergency epidemic prevention system. Once the emergency quarantine system is implemented, KDCA and public health centers nationwide will establish a reporting contact system and maintain a 24-hour emergency contact network before the Lunar New Year holidays. They will also promote preventive measures and encourage active reporting to healthcare institutions, pharmacies, childcare facilities, and children's homes.

In addition, in preparation for the Lunar New Year holidays when families and friends gather, the authorities will actively encourage Covid-19 vaccination for people aged 65 and older and those hospitalized or residing in vulnerable facilities.

"For a quick response, please report any gastrointestinal symptoms, such as vomiting, diarrhea, nausea, or abdominal pain, in two or more people or RSV cases in one or more people to the nearest public health center immediately," KDCA Commissioner Jee Young-mee said. "Please observe personal hygiene practices, like proper handwashing and coughing etiquette."

Jee also emphasized the need to get vaccinated against respiratory infectious diseases.

"In the run-up to the holidays, when family and friends are likely to gather, we strongly recommend that people aged 65 and older, who are at increased risk of severe or fatal illness if infected, and people hospitalized or residing in vulnerable facilities, who are at increased risk of infection during face-to-face interactions, get the new Covid-19 vaccine based on XBB.1.5," the commissioner added.