Influenza (Flu)

Influenza (Flu)

Influenza, a viral infection primarily targeting the nose, throat, bronchi, and occasionally the lungs, typically lasts around a week. Its onset is sudden, marked by high fever, muscle aches, headache, severe fatigue, dry cough, sore throat, and nasal congestion.

The virus spreads readily from person to person through droplets and small particles emitted when infected individuals cough or sneeze, leading to rapid transmission during seasonal outbreaks.

While most infected individuals recover within one to two weeks without medical intervention, the very young, elderly, and those with underlying health conditions are susceptible to severe complications such as pneumonia and death.

Seasonal influenza, caused by influenza virus types A, B, and C, primarily affects humans. Influenza A viruses, subtyped based on surface proteins, like A(H1N1) and A(H3N2), are common. While influenza A and B viruses are included in seasonal influenza vaccines, type C cases are rare.

Symptoms of seasonal influenza include sudden fever, dry cough, headache, muscle and joint pain, fatigue, sore throat, and runny nose. While most recover within a week, individuals at high risk, including young children, the elderly, and those with certain medical conditions, face a greater risk of complications or death.

Transmission occurs easily, particularly among crowded environments like schools and nursing homes. The virus spreads through infected droplets in the air or by touching surfaces contaminated with the virus.

Antiviral medications like adamantanes and neuraminidase inhibitors effectively prevent and treat influenza, although resistance can develop.

Seasonal epidemics occur annually during autumn and winter, leading to millions of severe illnesses and hundreds of thousands of deaths globally, with the elderly bearing the highest burden.

Influenza outbreaks pose significant public health and economic challenges, overwhelming healthcare systems and causing productivity losses. Vaccination remains the most effective preventive measure, significantly reducing the risk of illness, severe complications, and death, particularly among high-risk individuals.