Influenza, commonly known as the flu, is a respiratory illness caused by influenza viruses. It can range from mild to severe and can lead to serious complications, especially in high-risk groups.
Diagnosis:
- Clinical Presentation: Typical symptoms include fever, cough, sore throat, runny or stuffy nose, muscle or body aches, headaches, and fatigue. Some may experience vomiting and diarrhea, more common in children.
- Rapid Influenza Diagnostic Tests (RIDTs): Can detect influenza A and B virus antigens in respiratory specimens, providing results within 15 minutes. However, the sensitivity can vary.
- Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and Other Molecular Assays: More accurate and can provide results within a few hours to a few days.
- Viral Culture: Less commonly used due to longer turnaround times.
Differential Diagnosis:
- Common Cold: Caused by different viruses; symptoms are milder and usually don’t include fever or severe fatigue.
- COVID-19: Caused by the SARS-CoV-2 virus; symptoms overlap significantly with influenza.
- Bacterial Pneumonia: Can be a complication of influenza or a separate illness; typically more severe with higher fever and productive cough.
- Bronchitis: Inflammation of the bronchial tubes, usually without the systemic symptoms of influenza.
- Allergic Rhinitis or Sinusitis: Inflammation and congestion without systemic flu symptoms.
- Other Viral Respiratory Infections: Such as respiratory syncytial virus (RSV), particularly in children.
Management:
- Supportive Care: Adequate rest, hydration, and use of analgesics and antipyretics (like paracetamol or ibuprofen) to manage fever and aches.
- Antiviral Medication:
- Recommended for patients with suspected or confirmed influenza who are hospitalized, have severe illness, or are at high risk for complications.
- Medications like oseltamivir and zanamivir are most effective when started within 48 hours of symptom onset.
- Prevention:
- Annual influenza vaccination is the most effective method for preventing influenza and its complications.
- Good hygiene practices, including frequent hand washing and covering coughs and sneezes.
- High-Risk Groups: Early antiviral treatment is recommended for people at higher risk of flu complications, including young children, elderly individuals, pregnant women, and those with chronic health conditions.
- When to Seek Emergency Care: Immediate medical attention is needed if symptoms like difficulty breathing, chest pain, severe weakness, dizziness, confusion, or persistent vomiting occur.
Follow-Up:
Patients at high risk for complications should be monitored closely. Follow-up is necessary if symptoms worsen or do not improve within a few days of starting treatment.
Influenza can often be managed effectively with supportive care and antiviral medications when indicated. Prevention through vaccination and hygiene practices is key to reducing the spread and impact of the flu.