A child patient is seen at a hospital wearing a mask (Yonhap)

The recent surge in COVID-19 infections is stoking concerns of hidden, unchecked community spread, intensified by reduced data collection from Korean government agencies and a decline in testing rates.

Health authorities are reporting a steady rise in cases since the beginning of July as part of a summertime wave that is expected to peak later this month. That peak would coincide with the end of the vacation season and the return of students to schools.

The number of patients hospitalized with COVID-19 at 220 hospital-level medical institutions stood at 1,357 in the second week of August, according to the Korea Disease Control and Prevention Agency on Wednesday.

This is a sharp rise from 148 in the second week of July to 226 in the third week and 475 the following week. The corresponding figure for the first week of this month was 861. Most hospitalized patients were over 65 years old.

The KDCA explained that the summer wave was mainly spurred by a COVID-19 variant called KP.3, which has become the dominant strain here and is spreading quickly elsewhere around the globe. KDCA chief Jee Young-mee predicted that the virus would likely remain an infectious disease that spreads during the summer and winter.

However, health authorities no longer collect data as they used to, making tracking infected patients and their contact history more challenging.

Also, people test less, even if they feel the symptoms. Some mistake the virus for a cold as they usually share similar symptoms, such as a runny nose, cough or sore throat.

Moreover, corporate workers are often told to commute to work wearing facial covers when infected, rather than allowing them to work from home.

Most measures to contain the virus were scrapped in May 2023, when the Korean government announced it was exiting the state of COVID-19 national emergency and dropped its remaining antivirus mandates the following month.

Now, the KDCA advises self-isolation for patients for five days from the day of diagnosis, though it is no longer mandated. Before, there was a mandatory self-isolation period of seven days.

In light of the resurgence, authorities said they would secure and distribute additional COVID-19 treatments starting this week so that they could be delivered to pharmacies and allow those infected to access them easily.

The Ministry of Food and Drug Safety is currently monitoring how well self-testing kits are being supplied, as well as how they are being produced and distributed. Manufacturers plan to produce and provide over 5 million Makers of COVID-19 self-test kits by the end of this month.

The KDCA plans to ensure that the additional COVID-19 and influenza vaccines can be administered together in October, while the Education Ministry will recommend that students with COVID-19 symptoms recover at home.

In addition, the government set up a consultative body with experts to discuss the virus trend and antivirus measures regularly and held its first meeting late Tuesday. Officials have also expanded the response team against COVID-19 and are closely following the virus' mutations, hospitalization trends and developments overseas.

Health care experts underscored the importance of adhering to preventive measures to tame the virus, shrugging off the public's woes regarding the resurgence.

"People staying indoors with windows closed, visiting crowded places during the vacation season and traveling abroad are likely drivers of summer surges as the KP.3 variant spreads quickly. Also, medical institutions are no longer required to report confirmed patients to health authorities, lowering tracking levels," Shin Hyun-young, a family medicine professor at Seoul St. Mary's Hospital, told The Korea Herald.

"But this can be controlled if people mask in densely-populated areas and avoid catching and spreading droplets from spreading, which reduces the risk of the spread," the professor added, noting that the resurgence was not happening at an "alarming pace."

Chun Eun-mi, a lung specialist at Ewha Womans University Medical Center, highlighted the importance of testing, especially among those vulnerable to infection, as it is critical in containing the spread.

"For example, those who are older, immunocompromised or battling with chronic illness such as stroke or diabetes are at a much higher risk of getting the virus, but they tend to overlook the symptoms for simply a fever or a mild illness," Chun explained.

"Antigen rapid tests and treatments are available at pharmacies, so I recommend testing for COVID-19 if you feel any signs," the professor noted.