Influenza (Flu)

Influenza, commonly called the flu, is a contagious respiratory illness caused by influenza viruses. The flu can cause mild to severe illness, and at times can lead to death. The best way to prevent the flu is by getting a flu vaccine each year.

The flu is different from a cold. Flu usually comes on suddenly and symptoms are more severe. While most people recover within a week or two, some people develop complications that can be serious, especially older adults, young children, and people with certain health conditions.

Flu symptoms usually come on suddenly and can include:

Common Symptoms:

• Fever or feeling feverish/chills: Usually high (100-102°F or higher)
• Cough: Usually dry
• Sore throat: Common
• Runny or stuffy nose: Less common than colds
• Muscle or body aches: Often severe
• Headaches: Common
• Fatigue: Extreme tiredness
• Vomiting and diarrhea: More common in children

Symptoms usually last:

• 3-7 days for most people
• Fatigue may last longer
• Some symptoms may persist

Call Emergency Services (112 in Sweden) if:

• Difficulty breathing or shortness of breath
• Chest pain or pressure
• Severe dehydration
• Confusion or dizziness
• Severe muscle pain
• Seizures
• Signs of severe illness

Seek immediate care for children if:

• Fast breathing or trouble breathing
• Bluish skin color
• Not drinking enough fluids
• Not waking up or not interacting
• Fever with rash
• Severe symptoms

For mild to moderate flu:

1. Rest:

   • Get plenty of rest
   • Stay home from work/school
   • Allow body to fight infection
   • Don't overexert

2. Stay Hydrated:

   • Drink plenty of fluids
   • Water, broth, tea
   • Avoid alcohol
   • Watch for dehydration

3. Fever Management:

   • Over-the-counter fever reducers (acetaminophen, ibuprofen)
   • Follow instructions
   • Don't give aspirin to children/teens
   • Cool compresses

4. Symptom Relief:

   • Over-the-counter medications for symptoms
   • Cough suppressants (if needed)
   • Decongestants (if needed)
   • Follow instructions

5. Comfort Measures:

   • Warm baths
   • Humidifier
   • Gargle with salt water
   • Rest

6. Prevent Spread:

   • Stay home
   • Cover coughs and sneezes
   • Wash hands frequently
   • Avoid close contact
   • Don't share items

• Difficulty breathing
• Chest pain
• Severe dehydration
• Confusion
• Severe symptoms
• Signs of complications

• Symptoms not improving after a week
• High fever persisting
• Symptoms getting worse
• At risk for complications
• Questions about treatment
• Need for antiviral medications

• Mild to moderate symptoms
• Improving over time
• No complications
• No high-risk factors
• Following self-care measures

Diagnosing flu may involve:

1. Clinical Diagnosis:

   • Based on symptoms
   • Time of year (flu season)
   • Physical examination
   • Usually sufficient

2. Rapid Flu Tests (if needed):

   • Swab of nose or throat
   • Results in minutes
   • May not always be accurate
   • Used in some cases

3. Other Tests (if complications suspected):

   • Chest X-ray (if pneumonia suspected)
   • Blood tests
   • Other tests as needed

Most people recover with rest and fluids, but:

1. Antiviral Medications (if prescribed):

   • Can reduce severity and duration
   • Most effective if started early (within 48 hours)
   • May be recommended for high-risk people
   • Prescription only

2. Supportive Care:

   • Rest
   • Fluids
   • Fever reducers
   • Symptom relief

3. Complications Treatment:

   • Pneumonia: Antibiotics if bacterial
   • Other complications: As appropriate
   • Hospitalization if severe

Best Prevention: Annual Flu Vaccine:

• Get vaccinated every year: Best protection
• Everyone 6 months and older: Should get vaccine
• Especially important for: High-risk groups
• Reduces risk: Of getting flu and complications
• Even if you get flu: Usually milder if vaccinated

Other Prevention:

• Wash hands frequently: With soap and water
• Avoid close contact: With sick people
• Stay home when sick: Don't spread to others
• Cover coughs and sneezes: Use tissue or elbow
• Don't touch face: Especially eyes, nose, mouth
• Clean surfaces: Regularly disinfect
• Healthy lifestyle: Supports immune system

In flu:

1. Virus Entry: Enters through nose, mouth, or eyes
2. Infection: Infects respiratory tract
3. Immune Response: Body fights infection
4. Symptoms Develop: Fever, aches, fatigue
5. Recovery: Usually within 1-2 weeks

Complications Can Include:

• Pneumonia (bacterial or viral)
• Bronchitis
• Sinus infections
• Ear infections
• Worsening of chronic conditions
• Other complications

• May have more severe symptoms
• Higher risk of complications
• May have vomiting/diarrhea
• Watch for dehydration
• May need different approach

• Higher risk of complications
• May have atypical symptoms
• May take longer to recover
• Higher risk of hospitalization
• Vaccination especially important

• Older adults (65+)
• Young children (under 5, especially under 2)
• Pregnant women
• People with chronic conditions
• People with weakened immune systems
• Healthcare workers

People with flu are most contagious in the first 3-4 days after illness begins. Some people may be contagious for up to a week. Stay home until fever-free for 24 hours.

No. The flu vaccine cannot give you the flu. Some people may have mild side effects like soreness or low-grade fever, but this is not the flu.

Flu symptoms are usually more severe, come on suddenly, and include fever, body aches, and fatigue. Colds are usually milder and develop gradually.

In temperate climates, flu season typically runs from fall through winter, usually October to May, with peak activity in December through February.

No. Antibiotics don't work against viruses like the flu. They only work against bacterial infections. Antiviral medications may be prescribed in some cases.