{"id":3332,"date":"2026-10-14T08:36:27","date_gmt":"2026-10-14T01:36:27","guid":{"rendered":"https:\/\/naviva.com.vn\/?p=3332"},"modified":"2026-10-14T09:44:01","modified_gmt":"2026-10-14T02:44:01","slug":"seasonal-flu-when-it-peaks-symptoms-and-prevention","status":"publish","type":"post","link":"https:\/\/naviva.com.vn\/en\/seasonal-flu-when-it-peaks-symptoms-and-prevention","title":{"rendered":"SEASONAL FLU: WHEN IT PEAKS, SYMPTOMS, AND PREVENTION"},"content":{"rendered":"

1. Seasonal influenza and it causes<\/strong><\/span><\/h2>\n

Seasonal influenza is an acute respiratory infection caused by influenza viruses and represents a significant global public health burden. The virus spreads easily through respiratory droplets released when an infected person coughs or sneezes, as well as through contact with virus-contaminated surfaces. Influenza A viruses, particularly the H1N1 and H3N2 subtypes, and influenza B viruses are the main types responsible for seasonal flu.<\/span><\/p>\n

According to estimates from the World Health Organization (WHO), seasonal influenza causes approximately 1 billion cases worldwide each year, including 3\u20135 million cases of severe illness and 290,000\u2013650,000 deaths from influenza-associated respiratory complications.<\/span> [5<\/a>]<\/span><\/p>\n

2. When does seasonal influenza peak in Vietnam?<\/strong><\/span><\/h2>\n

Seasonal influenza typically peaks during the winter\u2013spring period (December to February) in northern Vietnam, when temperatures drop. In southern Vietnam and the Central Highlands, influenza circulates year-round, with cases tending to increase during the rainy season, from mid-May to November.<\/span><\/p>\n

However, recent surveillance data suggest that outbreaks can occur at any time of the year, including during the hot summer months. While 70\u201380% of cases were previously concentrated in winter and spring, summer and autumn now reportedly account for as much as 40\u201350% of annual cases.<\/span><\/p>\n

This shift may be influenced by climate change, air pollution, rapid urbanization, and the widespread use of air-conditioned indoor spaces, which create artificial cool, dry environments that may affect viral transmission. In addition, improved disease surveillance and greater public awareness of seeking medical care may contribute to the detection of sporadic cases throughout the year.<\/span> [3<\/a>]<\/span><\/p>\n

3. Symptoms of seasonal influenza<\/strong><\/span><\/h2>\n

Symptoms of seasonal influenza usually appear 1\u20134 days after infection and typically last about a week. They often develop suddenly and include:<\/span><\/p>\n