Influenza A (H1N1) – Novel Influenza Virus

Cause

Influenza A (H1N1) is caused by a novel strain of the influenza virus. This virus had not previously been identified in humans and resulted from a genetic reassortment of influenza viruses originating from humans, pigs, and birds.

Transmission

The virus is spread through respiratory droplets found in an infected person's saliva, mucus, and nasal secretions. Transmission can occur through:

• Coughing or sneezing
• Close contact with infected individuals
• Touching contaminated surfaces or objects and then touching the eyes, nose, or mouth

Symptoms

Symptoms usually develop within 1–3 days after exposure to the virus and are similar to those of seasonal influenza, including:

• High fever
• Headache
• Muscle aches
• Fatigue
• Cough
• Sore throat

Some patients may also experience:

• Diarrhea
• Nausea
• Vomiting
• Loose stools

Treatment

Patients with severe symptoms should seek medical attention immediately. Physicians may prescribe antiviral medication such as:

Oseltamivir

When administered within the first 48 hours after symptom onset, antiviral treatment can help improve recovery and reduce the severity of the illness.

For patients with mild symptoms, home care and supportive treatment are generally recommended:

• Take medications to relieve symptoms, such as acetaminophen (paracetamol) for fever and medications to reduce mucus
• Drink plenty of water and fruit juices
• Get adequate rest
• Eat a balanced and nutritious diet
• Stay in a well-ventilated environment
• Antibiotics are not necessary unless there is a secondary bacterial infection
• Follow medical advice and complete all prescribed medications to prevent drug resistance

Monitoring the H7N9 Avian Influenza Outbreak

Public health authorities continue to monitor the emergence of H7N9 avian influenza. Individuals traveling to affected areas or coming into direct contact with poultry should take appropriate precautions. H7N9 remains a virus of concern and requires ongoing surveillance to help prevent potential outbreaks.

Kasemrad Prachachuen Hospital

950 Prachachuen Road, Wong Sawang, Bang Sue, Bangkok 10800, Thailand

Tel. 0-2910-1600