Patient Information About Influenza A
What You Need to Know About Your Illness
Influenza A is a viral respiratory infection that typically causes fever, cough, body aches, headache, and fatigue that comes on suddenly. 1 Most people recover within a week without specific treatment, but you should know when to seek additional help. 1
Expected Course of Illness
- Symptoms typically last 5-7 days in otherwise healthy adults 2
- Fever, body aches, and headache usually improve first 1
- Cough and fatigue may persist for 1-2 weeks after other symptoms resolve 1
- You are contagious from 1 day before symptoms start until about 5-7 days after becoming sick 3
Home Care and Symptom Management
What You Can Do at Home
- Take paracetamol (acetaminophen) or ibuprofen for fever, body aches, and headache 1
- Rest as much as possible during the acute illness 1
- Drink plenty of fluids to stay hydrated 1, 4
- Avoid smoking and secondhand smoke 1
- Consider short-term use of decongestant nasal sprays, throat lozenges, or saline nose drops for symptom relief 1
Important Warning for Children
Never give aspirin to children or teenagers under 16 years old with influenza due to the risk of Reye's syndrome, a serious condition affecting the liver and brain 1, 5
When to Seek Medical Attention Immediately
You should contact your doctor or seek emergency care if you develop any of these warning signs: 1
- Difficulty breathing or shortness of breath 1
- Chest pain or pressure 1
- Persistent high fever (>38.5°C/101.3°F) lasting more than 3 days 1
- Symptoms that improve but then return with fever and worse cough (this may indicate bacterial pneumonia) 1, 5
- Severe or persistent vomiting (especially in children) 1
- Confusion or altered mental status 1
- Inability to keep fluids down 1
- Bluish lips or face 1
When to Re-Contact Your Doctor
- If you were prescribed antiviral medication and don't improve within 48 hours of starting it 1
- If you develop new symptoms like earache, sinus pain, or productive cough with colored sputum 1
- If your symptoms worsen after initially improving 1, 5
About Antiviral Medications
If Your Doctor Prescribed Oseltamivir (Tamiflu)
- Antiviral medications work best when started within 48 hours of symptom onset 4, 6
- The standard dose is 75 mg twice daily for 5 days 1, 6
- Take it with food to reduce nausea, the most common side effect 2
- These medications can shorten your illness by about 1-1.5 days and reduce severity 2, 3
- They may also reduce your risk of complications like pneumonia 2
Important Limitations
- Antiviral medications are NOT antibiotics and only work against influenza virus 6
- They do not work against other viruses that cause cold-like symptoms 7
- After 48 hours of symptoms, antivirals are generally not recommended for otherwise healthy people 4, 5
Preventing Spread to Others
Infection Control at Home
- Wash your hands frequently with soap and water or use alcohol-based hand sanitizer, especially after coughing or sneezing 1
- Cover your coughs and sneezes with a tissue and throw it away immediately, or cough into your elbow (not your hands) 1
- Avoid close contact with others, especially pregnant women, young children, elderly people, and those with chronic medical conditions 1
- Stay home from work or school until you have been fever-free for at least 24 hours without fever-reducing medication 3
- Avoid touching your eyes, nose, and mouth 1
Special Situations
If You Have Chronic Medical Conditions
You are at higher risk for complications if you have: 1
- Chronic lung disease (asthma, COPD)
- Heart disease
- Diabetes
- Weakened immune system
- Kidney disease
- Pregnancy
Contact your doctor early if you develop influenza symptoms, as you may benefit from antiviral treatment even if more than 48 hours have passed 1, 4
For Parents of Young Children
- Children under 1 year old should be evaluated by a doctor 1
- Watch for rapid breathing, difficulty breathing, or bluish color 1
- Ensure adequate fluid intake; contact your doctor if your child is not urinating regularly 1
- Drowsiness or difficulty waking should prompt immediate medical attention 1
Antibiotics and Influenza
Antibiotics do NOT treat influenza because it is caused by a virus, not bacteria 1, 4 Your doctor will only prescribe antibiotics if:
- You develop a bacterial complication like pneumonia or ear infection 1
- Your symptoms worsen after initially improving (suggesting bacterial superinfection) 1, 5
- You have specific risk factors and develop lower respiratory symptoms 1