URTI ll (Influenza)

Question 1

Common symptoms in influenza > common cold

Answer 1

1. Acute onset
2. Fever
3. Fatigue/malaise
4. Bodyaches/muscle aches
5. Chills
6. Cough, chest discomfort
7. Headaches

Question 2

Bimodal distribution of influenza

Answer 2

1. Northern strain (Dec-Feb)

2. Southern strain (May-July)

Question 3

Types of influenza

Answer 3

1. Type A
   - most severe illness
   - significant mortality in young person
   - pandemic and epidemic
   - many hosts
2. Type B
   - severe illness in older person
   - less severe epidemic
   - human host only
3. Type C
   - mild respiratory illness without seasonality
   - humans and swine hosts

Question 4

Complications of influenza (6)

Answer 4

1. Viral pneumonia
2. Bacterial pneumonia (esp Staph aureus, w >30% mortality)
3. Exacerbate underlying cardiac and pulmonary comorbidities
4. Febrile seizures
5. Respiratory failure
6. Myocarditis and pericardities

Question 5

Patients with high risk for influenza (6)

Answer 5

1. Children <5y/o
2. Elderly >=65y/o
3. Residents of nursing homes or long-term care facilities
4. Pregnant women or within 2 weeks post-partum
5. Obese w BMI >=40kg/m^2
6. Patients with chronic medical conditions (asthma, COPD, HF, DM, CKD, HTN, hyperlipidemia, immunocompromised)

Question 6

Prevention of influenza

Answer 6

1. Practice good personal hygiene
2. Adopt healthy lifestyle
3. Vaccination
   - >=6months for all
   - IM injection
4. Chemoprophylaxis
   - not routinely recommended to prevent sub-therapeutic dosing cos prophylaxis dose is 1/2 treatment dose

Question 7

Diagnosis of influenza

Answer 7

Inpatient - PCR

Limited for outpatient, most treated empirically

Question 8

When to empirically treat influenza

Answer 8

Within 48h onset of symptoms

• outpatients
• hospitalised
• high risks patients (6)
• severe, complicated or progressive illness

STRICTLY 48H

Question 9

Treatment for influenza

Answer 9

PO Oseltamivir 75mg x BD x 5 days

10 days if immunocompromised or critically ill

Question 10

Mechanism of action of Oseltamivir

Answer 10

Neuraminidase inhibitor

1. Inhibit protein cleavage
2. Inhibit the release of new viruses

Question 11

Side effects of Oseltamivir

Answer 11

1. Mild GI effects

2. Headache

Question 12

Which type(s) of influenza is Oseltamivir active against?

Answer 12

Influenza type A and B

Question 13

Does Oseltamivir req renal dose adjustment?

Answer 13

Yes