During the summer vacation period, as population movement and contact increase, and due to the heat, many people crowd indoors where air conditioning is used, respiratory viruses are resurfacing.
Notable respiratory infections include Novel Coronavirus Infection (COVID-19), Respiratory Syncytial Virus (RSV), and measles. Last summer, multiple respiratory infections occurred simultaneously, leading to cases of co-infection with two different viruses.
According to the Korea Disease Control and Prevention Agency on the 14th, COVID-19 hospitalization surveillance results indicate a continuous increase in COVID-19 patients in hospital-level medical institutions (221 places) over the past five weeks. The number of hospitalized patients increased from 63 at the end of June to 220 in early August, more than doubling in just over a month.
As of July this year, the COVID-19 variant virus NB.1.8.1 accounted for 87.1%, while others like XFG and JN.1 had lower shares. The Korea Disease Control and Prevention Agency plans to conduct vaccinations with the LP.8.1 vaccine, which has a higher neutralizing antibody level against circulating variants compared to the existing JN.1 vaccine, during the 2025-2026 vaccination season in October.
Korea Disease Control and Prevention Agency Director Lim Seung-kwan noted, "COVID-19 is becoming endemic, occurring once or twice a year, but high-risk groups such as the elderly and immunocompromised still need to exercise special caution to prevent infections."
The possibility of an RSV outbreak is also increasing. RSV spreads through the respiratory secretions of infected individuals or contaminated objects, and during an outbreak, one infected person can infect an average of three others.
Shin Yu-seop, a professor of allergy and immunology at Ajou University Hospital, explained, "RSV infection presents symptoms like fever, headache, runny nose, and sore throat that resemble those of a cold, making it difficult to distinguish. While most recover within one to two weeks, high-risk groups can experience severe complications such as pneumonia, which can lead to hospitalization or death, so caution is required."
RSV is commonly known to occur in children under 2 years old; however, there is a trend of increased cases among adults starting from 60 years old. The complications are numerous, placing a significant burden on patients. Professor Shin added, "The most common complications are pneumonia (24%), chronic respiratory disease (23.6%), and hypoxia or respiratory distress (22%), and the risk due to RSV infection increases when there are underlying conditions such as lung or heart disease."
As of early June in Korea, vaccinations with the UK's GlaxoSmithKline (GSK) vaccine Arexvy have been underway targeting individuals aged 60 and over. In clinical trials, Arexvy demonstrated an effectiveness of 82.6% in preventing lower respiratory tract infections from RSV in those aged 60 and over, and it was even higher at 94.6% in individuals with comorbidities.
Recently, the number of measles cases has also increased. As of the 9th of this year, the total number of measles cases in Korea is 68, an increase of 1.4 times compared to the same period last year (47 cases). Among these, 49 cases (72.1%) were imported from abroad, while 19 cases (27.9%) were related to imported cases.
Measles is a virus respiratory infection transmitted through the air. Its main symptoms include fever, rash, cough, runny nose, and conjunctivitis, with an incubation period of 7 to 21 days. Hospitalization is required for complications such as otitis media, pneumonia, or dehydration due to diarrhea and vomiting.
Measles has a transmission rate of over 90% when a person without immunity contacts an infected patient; however, it can be sufficiently prevented through vaccination. Director Lim Seung-kwan of the Korea Disease Control and Prevention Agency stated, "Individuals who have not been vaccinated against measles or whose vaccination status is uncertain should complete their vaccinations before traveling abroad," and added, "If symptoms suggesting measles occur, it is important to visit a medical institution promptly, inform them of your travel history, and seek treatment."