Microbiology of Respiratory tract infections

Question 1

Influzena clinically presents with what symptoms?

Answer 1

o	Fever of up to 40C
o	Malaise - uncomfortable feeling
o	Myalgia - muscle pain
o	Headache
o	Cough
o	Prostration - weakness

Question 2

Types of Classical Flu

Answer 2

Influenza A and Influenza B

Question 3

Haemophilus influenzae

Answer 3

A bacterium that can be a secondary invader in flu patients but is not the primary cause of flu.

Question 4

How is influenza transmitted?

Answer 4

By droplets or through direct contact with respiratory secretions of an infected individual. This could be through:
o	Intubation or extubation
o	Manual ventilation
o	CPR
o	Bronchoscopy
o	Surgery
o	Dental procedures

Question 5

Complications of Influenza

Answer 5

Primary influenzal pneumonia
Secondary bacterial pneumonia
Bronchitis
Otitis media

Question 6

Where is Primary Influenzal pneumonia usually seen?

Answer 6

During most pandemic years and is of high mortality

Question 7

Where is Secondary influzenal pneumonia usually seen?

Answer 7

In infants and elderly among other vulnerable subgroups. It is the most common cause of death in influenza.

Question 8

Treatment for the Flu

Answer 8

Rest, Fluids and paracetamol.
It can be treated with antivirals such as oseltamivir and zanamivir - HOWEVER, these are only really given to patients at risk of complication in accordance with NICE guidelines.

Question 9

Why does Flu often come in winter epidemics?

Answer 9

Due to minor mutations in the surface proteins of the virus - antigenic drift.
Pandemics are only of Influenza A and require antigenic drift, segmented genome and/or animal reservoir.

Question 10

Avian flu

Answer 10

Highly pathogenic
Transmitted from bird to human but not readily from human to human..
High mortality.

Question 11

Why is PCR used?

Answer 11

Used to detect the influenza virus. It is taken through a nasopharyngeal swab.

Question 12

What are Killed vaccines?

Answer 12

They are viruses that are inactivated given to patients at risk of complications and health care workers.

Question 13

What are live attenuated vaccines?

Answer 13

They are administered intra-nasally and are more effective in children.

Question 14

How can Community acquired pneumonia be caused?

Answer 14

Mycoplasma Pneumoniae (most common) - usually seen in young adults and children.
Coxiella burnetti - uncommon and sporadic, can be from sheep and goats.
Chlamydia (psittaci) - uncommon, caught from birds.

Question 15

What drugs respond to Community acquired pneumonia?

Answer 15

Tetracycline and macrolides (clarithromycin).
The mortality varies but it is generally lower than classical bacterial pneumonia.
They can be identified by serology and virus detection (PCR).

Question 16

What is Bronchiolitis?

Answer 16

Common lower respiratory tract infection that presents in the 1st or second year of life.

Question 17

What are the symptoms of Bronchiolitis?

Answer 17

o	Fever
o	Coryza
o	Cough
o	Wheeze
o	Grunting
o	Decreased PaO2
o	Intercostal/Sternal indrawing

Question 18

What are the complications with Bronchiolitis?

Answer 18

It can lead to respiratory or cardiac failure. Mostly due to respiratory syncytial Virus.
Confirmed by PCR

Question 19

What is Metapneumovirus?

Answer 19

Respiratory syncytial virus and metapneumovirus infections cause seasonal lower respiratory tract disease, particularly in infants.

Question 20

Where is the Metapneumovirus usually seen?

Answer 20

It is world wide and fund in all ages. Most children have the antibody by age 5.
It is the second most common cause of bronchiolitis and has similar symptoms to RSV.
Confirmed by PCR.

Question 21

What is Chalmydia trachomatis?

Answer 21

An STI which can cause infantile pneumonia and is diagnosed by PCR.

Question 22

How is Chalmydia pneumoniae transmitted?

Answer 22

is transmitted person to person and is mostly mild.