Viral Respiratory Infections Flashcards
List 5 types of viral respiratory infection.
Common cold Croup Lower respiratory tract infections (LRTIs) Pneumonia Influenza
Define croup.
Acute inflammation and obstruction of the respiratory tract, involving the larynx and main air passages (trachea and bronchi)
Define bronchiolitis.
Inflammation of the bronchioles due to viral infection, especially respiratory syncytial virus (RSV)
List 2 causes of the common cold.
Rhinovirus (80%)
-Groups A, B and C
Coronavirus (15-20%)
Describe the symptoms of a common cold. (2)
How is treated? (1)
SYMPTOMS:
General malaise
Fever
TREATMENT:
Supportive treatment only
Describe the symptoms of croup. (6)
What can happen in severe croup? (1)
Distinctive "barking" cough Stridor Laryngitis High HR Restlessness Cyanosis
SEVERE CROUP:
Difficulty breathing
Which viruses can cause croup? (1)
Parainfluenza viruses 1-4
How do you treat croup?
Supportive treatment
Describe the pathophysiology of bronchiolitis. (2)
- Bronchioles become swollen, and lining cells die
- Bronchioles become blocked with debris and mucous
a. Therefore air cannot reach the alveoli
b. This causes hypoxia and breathlessness
Describe the clinical features of bronchiolitis. (5)
Breathlessness Hypoxia Wheeze General malaise Flu-like symptoms
Which viruses can cause bronchiolitis? (1)
Respiratory syncytial virus (RSV)
Who is at high risk of RSV infection?
Young children
Immunocompromised patients
Chronic lung disease
Elderly patients
How do you prevent RSV infection?
How do you treat RSV infection?
PREVENTION:
Cohorting
PPE
Handwashing
TREATMENT:
Ribavirin (virazole)
Palivizumab (synagis)
Describe the advantages and disadvantages of:
a) Ribavirin (2)
b) Palivizumab (3)
RIBAVIRIN:
Administration IV, oral or inhaled
Many adverse effects
PALIVIZUMAB:
Monthly IM injection
Reduces hospitalisation of high risk infants by 45%
Very expensive
Describe the clinical features of viral pneumonia. (10)
Fever Cough (with sputum/phlegm production) Shortness of breath Pleuritic chest pain Haemoptysis
Other symptoms:
- Headache
- Nausea and vomiting
- Arthalgia
- Fatigue/weakness
- Cyanosis
Which viruses can cause viral pneumonia? Which ones are common in:
a) Adults? (1)
b) Children? (3)
c) Immunocompromised patients? (2)
IN ADULTS:
-Influenza virus
IN CHILDREN:
- Influenza virus
- Respiratory syncytial virus (RSV)
- Type 3 parainfluenza virus
IN IMMUNOCOMPROMISED PATIENTS:
- Influenza virus
- Cytomegalovirus (CMV)
What causes influenza epidemics?
What causes influenza pandemics?
Antigenic drift - “gradual changes in virus structure caused by mutations, allowing it to evade the immune system”
Antigenic shift - “significant changes in virus structure caused by large mutations, allowing the virus to jump species from animals to humans”
List 5 common complications of influenza infection.
List 5 uncommon complications of influenza infection.
COMMON COMPLICATIONS: Acute otitis media Sinusitis Pneumonia Exacerbation of underlying diseases Dehydration
UNCOMMON COMPLICATIONS: Encephalopathy Reye's syndrome Myositis Myocarditis Febrile seizures
List 8 risk factors for complications of influenza infection.
Extremes of age Underlying lung conditions Chronic CVD, renal or hepatic disease Haematological disease Metabolic disorders Immunosuppression Pregnancy Long term aspirin therapy
How do you treat influenza infection? (2)
Adamantanamine derivatives
Neuraminidase inhibitors
Give 3 examples of neuraminidase inhibitors used to treat influenza.
Tamiflu (oseltamivir)
Rapivab (peramivir)
Relenza (zanamivir)
List 5 benefits of PCR testing for viral DNA.
Highly sensitive Rapidly developed Can detect multiple pathogens Semi-quantitative Very quick
