The World Health Organization (WHO) estimates 3 to 5 million cases of severe flu and 650,000 flu-related deaths globally each year. Most deaths occur in people over 65 and those with underlying health conditions. In Vietnam, the Ministry of Health recorded nearly 290,000 flu cases in 2024, with several outbreaks.
Seasonal flu is an acute respiratory infection caused by the influenza virus. The virus spreads easily through droplets produced when an infected person coughs, sneezes, or talks. Common symptoms include high fever, muscle aches, headache, dry cough, nasal congestion, and fatigue. While most people recover within a few days, some may experience serious complications.
Associate Professor Nguyen Thi Thu Hoai, Director of the Institute of Cardiology, says the flu is not just a simple respiratory infection; it can exacerbate existing chronic conditions such as heart failure, asthma, COPD, and diabetes. Seasonal flu can worsen symptoms in heart failure patients and increase the risk of cardiovascular complications even in healthy individuals.
Flu can cause fever, dehydration, and increased oxygen demand, making the heart work harder. This can lead to decompensated acute heart failure in heart failure patients and increase the risk of arrhythmias. Patients with hypertension or heart failure are often prescribed vasodilators and diuretics. When they get the flu, they may experience dehydration and vasodilation due to fever. Therefore, they should consult their cardiologist immediately to adjust these medications.
In some cases, seasonal flu can lead to acute myocarditis, causing rapid arrhythmias and rapidly progressive acute heart failure. Moreover, seasonal flu often causes a systemic inflammatory response, increasing the risk of blood clotting disorders. This, in turn, increases the risk of myocardial infarction and stroke in patients with atherosclerotic cardiovascular disease.
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A patient receives a seasonal flu vaccination. Photo: Ngan Duong |
A patient receives a seasonal flu vaccination. Photo: Ngan Duong
"Many older adults mistakenly believe that the flu is just a common illness and neglect an effective preventive measure: the flu vaccine," Dr. Hoai said, recommending annual flu vaccination to reduce the risk of cardiovascular events by 15-45%. The groups that should be vaccinated include cardiovascular patients, people with heart failure or after coronary interventions, and those with hypertension, valvular heart disease, or cardiomyopathy.
The WHO recommends annual flu vaccination because the influenza virus constantly changes its antigens. The circulating flu strains vary each year, so the vaccine needs to be updated seasonally to ensure immune effectiveness. In Vietnam, the flu season lasts from October to April of the following year.
In addition to vaccination, people should practice simple but effective preventive measures: Wash their hands frequently, wear masks in public places, cover their mouths when coughing or sneezing, maintain personal hygiene, and ensure a well-ventilated and clean living environment.
Le Nga
