Recently, with temperature fluctuations and more time spent indoors, confirmed influenza (flu) cases are rising again, and infections among children and adolescents are spreading quickly. In particular, children and teens who spend much time in group settings such as schools and private academies face faster transmission and a higher risk of cluster outbreaks, requiring special caution.

The current flu wave in the country is spreading rapidly, centered on infants through adolescents. The proportion of patients is highest especially in ages 7-12 and 1-6. Alongside influenza, other respiratory illnesses such as RSV are circulating simultaneously, making the ‘two- to threefold viral threat’ a reality in winter.

Influenza is an acute respiratory infection caused by influenza A and B viruses, characterized by systemic symptoms such as high fever, chills, muscle aches, and headache. Infants and toddlers may also have dehydration, vomiting, loss of appetite, and fussiness; if high fever lasts for 3 days or more, or if breathing difficulties, cyanosis, or seizures appear, immediate medical care is needed.

Children have weaker immunity than adults, so complications such as high fever, dehydration, pneumonia, and otitis media can occur more easily, and transmissibility tends to rise explosively in group settings.

Yang Mu-yeol, a pediatric specialist at H+ Yangji Hospital, explained, “Recently, pediatric flu cases have been increasing, and infants and toddlers face a higher risk of complications such as dehydration and pneumonia, so careful management is needed from the early stage of symptoms.” He also emphasized, “Flu can be largely prevented through vaccination and adherence to basic hygiene practices, and antiviral treatment within 48 hours of symptom onset is key to speeding recovery.”

In addition to antivirals, symptomatic treatment such as antipyretics and analgesics is provided, and to prevent dehydration due to high fever, water and oral rehydration drinks should be taken frequently. To support recovery and prevent secondary infections, adequate rest is needed, and attending school or daycare should be avoided for about one day after the fever subsides.

The usual incubation period of flu is 1-4 days, and if symptoms such as sudden high fever (38~40℃), respiratory symptoms (cough, runny nose, sore throat), severe fatigue and muscle aches, loss of appetite, vomiting, and diarrhea appear, influenza should be suspected. In particular, if high fever persists for 3 days or more, or if breathing difficulties, persistent vomiting, or seizures occur, hospital care is required.

Because children are at high risk for influenza complications, annual flu vaccination is recommended; it takes about two weeks for antibodies to form after vaccination, so getting vaccinated before the season is effective. For prevention, practice basic hygiene such as handwashing and cough etiquette; because dry environments facilitate viral spread, regular ventilation and maintaining 40-60% humidity are needed. In group settings, wearing masks is recommended when possible, and adequate hydration and a balanced diet are also important.