01/04/2026
Influenza (Flu): Definition, Causes, Symptoms & Home Care
What Is the Flu?
Influenza (commonly called flu) is an acute viral infection of the respiratory tract caused by influenza viruses. It affects the nose, throat, and lungs and can range from mild illness to severe disease, especially in young children, older adults, pregnant individuals, and people with chronic medical conditions.
Causes
Flu is caused by influenza viruses, mainly:
Influenza A (most common, causes outbreaks and pandemics)
Influenza B (usually causes seasonal illness)
The virus spreads through:
Respiratory droplets from coughing, sneezing, or talking
Close contact with an infected person
Touching contaminated surfaces and then touching the mouth, nose, or eyes
Symptoms
Symptoms usually begin suddenly and may include:
Fever or chills
Cough (usually dry)
Sore throat
Runny or blocked nose
Headache
Muscle or body aches
Fatigue or weakness
Loss of appetite
Nausea, vomiting, or diarrhea (more common in children)
Flu vs Common Cold
Flu: Sudden onset, high fever, severe body aches, marked fatigue
Cold: Gradual onset, milder symptoms, usually no high fever
Fluid Management in Flu
Flu often causes fever, sweating, poor appetite, and reduced intake, increasing the risk of dehydration.
Recommended Fluids
Water (frequent small sips)
Oral Rehydration Solution (ORS)
Warm clear soups or broths
Diluted fruit juice (1:1 with water)
Herbal teas (non-caffeinated)
Tips
Drink even if not thirsty
Aim for light yellow urine
Take small, frequent sips if nauseated
Home Remedies & Supportive Care for Flu
Rest: Essential for recovery
Adequate fluids: Prevent dehydration
Warm fluids: Help soothe sore throat and cough
Honey: For cough (avoid in children 3 days
Confusion or extreme drowsiness
Inability to keep fluids down
Signs of dehydration
Worsening symptoms after initial improvement
Prevention
Annual influenza vaccination
Frequent handwashing
Cover mouth and nose when coughing or sneezing
Stay home when sick to prevent spread
Key Message
Flu is a contagious viral illness that can usually be managed at home with rest, fluids, and supportive care, but early recognition of warning signs is essential to prevent complications.
