Seasonal flu is an acute respiratory infectious disease caused by the Influenza virus that infects the nose, throat and lungs. In Vietnam, seasonal flu usually circulates year-round, but tends to be concentrated in winter and spring. Experts warn that the peak of flu season can fall around February-April and September-October every year.
According to the World Health Organization (WHO), there are about one billion cases of seasonal flu each year, of which 3-5 million are severe and 290,000 to 650,000 die. In Vietnam, flu occurs year-round, with more than 287,000 cases and 8 deaths recorded in 2024.
Associate Professor, Dr. Tran Dac Phu, former Director of the Department of Preventive Medicine, made important comments on the seasonal flu situation in Vietnam.
He stressed that cold weather in winter creates favorable conditions for respiratory diseases, including influenza, to develop and spread. Human resistance also decreases during the transitional season, along with socializing and gathering in large numbers, increasing the risk of disease.
Influenza strains can change every year, and there is no cross-immunity between strains. Therefore, a person can get influenza A and then influenza B, or even get influenza A multiple times with different strains. In particular, in crowded classroom environments, influenza viruses can easily spread when there is a source of infection.
To prevent the spread of influenza in schools, Associate Professor Dr. Tran Dac Phu recommends that parents and schools should keep students with influenza home from school. At the same time, preventive measures such as wearing masks, washing hands with soap, disinfecting desks and chairs and school supplies should be implemented. Annual flu vaccination is also very important to increase resistance to disease.
In addition, Mr. Phu emphasized that although influenza is usually a self-limiting disease and does not necessarily require hospitalization, it can cause dangerous complications such as respiratory failure, ear infections, pneumonia, bronchitis, meningitis and secondary infections. Therefore, when there are signs of worsening, especially in the elderly and those with underlying diseases, the patient should be taken to the hospital promptly.
Seasonal flu is usually mild and resolves within 2-7 days with symptoms of fever, headache, muscle pain, fatigue, runny nose, sore throat, cough and recovery. However, the disease can cause complications or death in high-risk groups such as people aged 65 and over, young children, pregnant women, people with underlying medical conditions...
He also noted that cold weather can increase other diseases such as pneumonia in young children, winter diarrhea caused by viruses and diseases that are vaccinated but not fully vaccinated such as diphtheria, whooping cough and measles.
