Respiratory viruses

Question 1

What are the symptoms of ‘seasonal flu’?

Answer 1

STOP
Sore throat
Temperature
Onset (sudden)
Pains and muscle aches

Question 2

What kind of virus is the influenza virus?

Answer 2

Orthomyxoviridae
Types A, B, C

Question 3

Which feature of influenza leads to its epidemic nature?

Answer 3

Variation in its two envelope glycoprotein antigens
H (hemagglutinin) binds to cell
N (neuraminidase) protein cleaves new virus to allow spread

Question 4

Discuss the treatment of influenza

Answer 4

M2 inhibitors
- only influenza A
Neuraminidase inhibitors
- influenza A and B

Question 4

Discuss the difference in antigenic drift vs shift

Answer 4

Drift
- minor change, same subtype, cause by point mutations, causes epidemics
Shift
- major change, new subtype, cause by gene segment exchange, causes pandemics

Question 5

Name M2 inhibitors

Answer 5

Amantidine
Rimantidine

Question 6

Name neuraminidase inhibitors

Answer 6

Oseltamivir
Zanamivir

Question 7

Which influenza vaccine is more effective in children?

Answer 7

Live attenuated

Question 8

Name complications of influenza

Answer 8

Pneumonia
ARDS
Organ failure
MI
Stroke
Heart/brain inflammation

Question 9

What features of influenza leads to enhance susceptibility to s.pneumo?

Answer 9

1. Destruction of respiratory epithelium and exposure of BM
2. Up-regulation of molecules used by bacteria as receptors
3. Impaired function of immunological cells

Question 10

Differentiate the clinical features of influenza vs RSV

Answer 10

RSV has more
- nasal congestion
- wheezing
- sputum production
and less
- fever
- myalgias
- GIT symptoms

Question 11

Discuss treatment of RSV infection

Answer 11

Generally supportive

In transplant patients:
Ribavirin
IVIG
Palivizumab (monoclonal Ab)

Question 12

Discuss immunisation strategies for RSV

Answer 12

1. Recombinant vector based vaccines
   - use modified replication defective virus
   - assoc with thromboembolism
2. Nucleic acid based vaccines
   - based on introducing mRNA encoding RSV antigens
3. Protein based vaccines
   - whole-inactivated virus
   - mostly for older adults and mothers
4. Live attenuated vaccines
   - mimic natural infection
   - do not appear to cause vaccine enhanced disease
5. Monoclonal antibodies
   - passive immunisation

Question 13

Which family does human metapneumovirus belong to?

Answer 13

Paramyxovirus

Question 14

Discuss features of human metapneumovirus

Answer 14

Common in children
Closely related to RSV and similar presentation although less severe
Droplet tranmission
Winter outbreaks
PCR most sensitive
Supportive treatment

Question 15

Discuss the features of measles

Answer 15

Airborne transmission
Highly contagious
Incubation 9-14d
Multilobar reticulonodular infiltrate on CXR
Secondary bacterial infections common

Question 16

Name complications of measles infection

Answer 16

Hepatitis
Encephalitis
Keratitis
Mesenteric adenitis
Severe diarrhoea

Question 17

Discuss the clinical presentation of measles

Answer 17

Prodrome 2-8d
- fever, anorexia, cough, coryza, conjunctivitis, koplik spots
Maculopapular erythematous rash from face to extremities

Question 18

What is the incubation period of VZV?

Answer 18

2 weeks

Question 19

Discuss diagnosis of VZV

Answer 19

Clinical (rash + pneumonia)
Tzank smear (lesion scrapings)
Direct immunofluorescence
BAL PCR

Question 20

Discuss treatment of VZV pneumonia

Answer 20

IV acyclovir for 5-7d

Question 21

What was the intermediate host of SARS-CoV-1?

Answer 21

Civet cat

Question 22

What was the intermediate host of MERS-CoV?

Answer 22

Camel

Question 23

What was the intermediate host of SARS-CoV-2?

Answer 23

Pangolin

Question 24

What were the 4 major structural proteins targeted for covid-19 vaccine?

Answer 24

Spike protein
Membrane protein
Envelope protein
Nucleocapsid protein