Influenza

Question 1

Two main types of influenza virus are A and B.

Which has the capacity to undergo antigenic shift (major change in H and N antigens) associated with pandemic infections?

Answer 1

Influenza A

Question 2

What antigens coat the surface of an influenza virion?

Answer 2

Haemaglutinin

Neuroaminidase

Question 3

How does influenza present clinically?

Answer 3

Incubation period= 1-3 days 
Severe headache and fever
Soar throat, dry cough
Generalised aching of limbs
May last several weeks

Question 4

How is flu differentiated from common cold?

Answer 4

Flu= fever, dry cough, general aching

Cold= runny nose

Question 5

Diagnosis of flu?

Answer 5

Lab diagnosis is not usually necessary
Serology shows rise in antibody titre
Virus demonstrated in throat/nasal secretions—> culture

Question 6

Symptomatic treatment of flu?

Answer 6

paracetamol, bed rest, maintenance of fluid intake

Question 7

Antibiotics to prevent secondary infection is needed in flu patients with what conditions?

Answer 7

chronic bronchitis, heart or renal disease

Question 8

In a pandemic neuroaminidase inhibitors are offered to all those with suspicious symptoms. Name 2?

Answer 8

Zanamivir, Oseltamivir

Question 9

What is a common complication of flu?

Answer 9

Pneumonia- viral or due to secondary bacterial infection (staph aureus is most common)

Question 10

What prophylaxis is available for flu?

Answer 10

Influenza vaccine prepared from current strains

Effective in 70% and lasts for about a year