Influenza

Question 1

What is influenza?

Answer 1

Viral infections occurring mainly in the winter months

Highly contagious with droplet spread

Question 2

What causes influenza?

Answer 2

• Have three types of influenza viruses: A, B and C

A and B cause most clinical diseases

Question 3

What increases the risk of developing influenza?

Answer 3

Elderly

Immunocompromised

Question 4

What are the presentations of influenza?

Answer 4

Fever

Dry cough

Loss of appetite and sleep

Exhaustion

Myalgia - muscle ache and pain

Coryzal symptoms - sneezing, nasal obstruction and rhinorrhoea

Question 5

What is the gold-standard for diagnosing influenza?

Answer 5

Diagnosed by PCR

Question 6

How is influenza managed?

Answer 6

Uncomplicated case

1. Supportive - stay home and rest
2. Painkillers - paracetamol
3. Antivirals - high-risk groups like the elderly etc.

If severe/ progressive:

1. Neuraminidase inhibitor for 5 days min or until improvement
2. Corticosteroids if first line is C

Question 7

How is influenza controlled globally?

Answer 7

Prevention

Vaccine for

• Pregnant women
• Elderly >65
• Children - 6 months - 5 years
• Underlying chronic health condition
• Healthcare workers

Vaccines for children - live vaccine given intranasally at age 2-3 years, then yearly

Otherwise - injectable vaccine given

Question 8

What can happen with untreated influenza?

Answer 8

Can develop into viral pneumonia - build-up of inflammatory mediators, WBC, cytokines etc

Get leakage of interstitial fluid from blood