Respiratory Infections - Viruses Flashcards
1
Q
When do the following respiratory viruses peak?
- RSV
- Rhinovirus
A
- RSV - peak in October/November
- Rhinovirus - spike in admissions in September continuing throughout winter
2
Q
What viruses are linked to the following conditions
- Bronchiolitis
- Croup
- Upper respiratory tract infections
- Tonsilitis
- Pneumonia
- Infectious mononucleosis
A
- BRONCHIOLITIS- RSV/Parainfluenza/adenovirus
- CROUP - RSV/(para)influenza virus
- URTI - All aforementioned + rhinovirus and coronavirus
- TONSILITIS - EBV and adenovirus
- Pneumonia - (para)influenza, adenovirus, RSV
- Infectious mononucleosis - EBV and CMV
3
Q
Describe respiratory syncytial viruses
A
- LRTI in young children - bronchiolitis - usually in children under 12 months. Wheezing and increased respiratory rate. Cyanosis in severe cases. PNEUMONIA
- URTI in adults - common cold. Pneumonia in elderly
4
Q
What are the main characteristics of respiratory syncytial virus?
A
- Causes mild cold like symptoms in older healthy children/adults
- Annual epidemic during winter months in temperate clinics
- More common in rainy season during tropical climates
- Re-infection can occur
5
Q
How can RSV be treated?
A
- Antivirals e.g ribivarin - in complicated cases
- IV immunoglobulin in specific cases
6
Q
Describe rhinovirus.
A
- Most frequent cause of common cold
- Droplet spread and limited to URT
- RNA virus from Picornaviridae family
- Detected by PCR
7
Q
Describe coronavirus.
A
- Second most common cause of common cold
- Milder infection
- 50% - asymptomatic. EXCEPTION - COVID-19
- RNA Virus from Coronaviridae family
8
Q
Describe SARS CoV
A
- Fever > 38 degrees
- Respiratory symptoms, SOB
- CXR, with pneumonia
- Droplet, contact spread
- Detected by PCR and cell culturing
9
Q
Describe MERS-CoV
A
- Typical symptoms - fever, cough and SOB
- Pneumonia - common - not always present
- GI symptoms may occur
- High mortality
- Attributed to human-animal interactions
10
Q
Describe pathogenesis of patients with SARS CoV-2
A
- Viral entry
- Initial immune responses attracts viral specific T cells to site of infection
- Infected cells eliminated before virus can spread. Recovery
- In sever cases, aberrant immune response
11
Q
Describe adenovirus.
A
- Droplet and contact transmission
- Usually causes URTI
- 50% of infections - asymptomatic
- Occasionally severe bronchopneumonia in infants
- DNA virus
- Viral antigen detection by PCR
12
Q
Describe metapneumovirus.
A
- Related to RSV
- Infections in infants, young children
- Mild URTI, can lead to bronchiolitis and pneumonia
- Diagnosed in lab by serology and PCR
13
Q
Describe parainfluenza
A
- Major cause of croup, pneumonia and bronchiolitis
- 4 serotypes
- Droplet/contact spread
- RNA virus from Paramyxoviridae family
- Diagnosed in lab by PCR antigen detection
14
Q
Describe Influenza A and B
A
- Influenza A - outbreaks occur - causing epidemics. Multiply and spread between animals - example are brids
- Influenza B - less severe disease and smaller outbreaks. Predominantly found in humans and burden of disease mostly in children
15
Q
Describe influenza virus
A
- Causes illness in all age groups
- Transmitted by aerosols
- Sudden onset
- Diagnosed in lab by PCR
- Causes fever, chills and myalgia
- Complications - secondary bacterial pneumonia, rarely viral pneumonia, myocarditis