Why is flu easy to break out during back-to-school season?

According to Dr. Dao Huu Nam, Head of the Department of Intensive Care, Center for Tropical Diseases, National Children's Hospital, the latest data from the World Health Organization (WHO) and the US Centers for Disease Control and Prevention (CDC) shows that seasonal flu – which is considered a common disease in winter and spring – is tending to circulate all year round. In particular, the fall of 2025 witnessed a marked increase in the number of cases and hospitalizations, with children and the elderly being the most affected.

In many countries in Asia, Europe and North America, hospitals have recorded a 1.5- to 2-fold increase in hospitalizations due to seasonal flu complications compared to the same period last year.

In Vietnam, the Ministry of Health warned that the rate of children hospitalized with influenza in September - October 2025 will increase rapidly, especially in large cities where population density is high and weather is erratic.

The National Children's Hospital has recorded a sharp increase in the number of children coming to the clinic due to seasonal flu in the past two months. Doctors emphasized that many cases were hospitalized due to complications. Pneumonia, otitis media, convulsions due to high fever - dangerous complications often found in children with flu.

Annual influenza vaccination remains the most effective way to reduce the risk of illness and hospitalization.

According to experts, when students return to school en masse after summer vacation, the risk of outbreaks Infectious diseases, especially seasonal flu, are on the rise due to the closed, crowded classroom environment and the erratic changes in the weather during the changing seasons. The flu virus spreads very quickly, especially among young children – a group with an incomplete immune system and limited awareness of personal hygiene.

According to the World Health Organization and the Vietnamese Ministry of Health, the most effective way to prevent influenza is to get vaccinated every year. Seasonal influenza vaccines are regularly updated according to new virus strains, helping the body create antibodies, reducing the risk of disease and preventing serious complications.

Children 6 months of age and older should be vaccinated. flu vaccine every year, ideally 2–4 weeks before the epidemic season to give the body enough time to build immunity.

In addition to young children, groups that need vaccination also include: People over 50 years old, people with chronic diseases (cardiovascular, diabetes, COPD...), pregnant women, people with weakened immune systems, people who have just had surgery or given birth.

For children under 6 months of age who are not eligible for vaccination, the risk of infection is still very high if relatives have not been vaccinated. In particular, premature babies and babies with underlying diseases such as heart failure, metabolic disorders, etc. need to be proactively protected by fully vaccinating their caregivers.

Associate Professor, Dr. Tran Dac Phu, former Director of the Department of Preventive Medicine, warned that influenza is a common disease but should never be taken lightly. In fact, there have been many cases of serious complications due to subjectivity, especially in young children and people with underlying diseases. Annual flu vaccination is still the most effective measure to reduce the risk of infection and hospitalization.

In addition to vaccination, it is important to wash your hands regularly with soap or antiseptic solution; cover your mouth when coughing, and limit close contact when having flu symptoms. You should wear a mask in public places, especially when children go to school or crowded playgrounds; keep your house well-ventilated, clean toys and household items regularly; ensure adequate nutrition to help strengthen your child's resistance.

Source: https://baolangson.vn/vi-sao-cum-de-bung-phat-trong-mua-tuu-truong-5057528.html