COVID Flashcards
(40 cards)
What is SARS-COV2 and what does it stand for?
Severe Acute Respiratory Syndrome from the Coronavirus 2
Illness caused by the COVID-19 virus
What other viruses does SARS-COV2 share genetic materials with?
SARS from 2002-2003 and MERS from 2012 which are 80% similar to it
Where did COVID-19 come from?
(Etiology, 3 points)
- Started in Wuhan, China - traced back to a fish/meat market
- Believed to have come from bats - 96.2% genetic similarity to bat coronavirus
- Underwent antigenic shift from bat to human, unknown if intermediate carrier was involved
What 6 components is the COVID virus made of?
- Spike Protein
- Hemagglutinin Esterase Protein
- Envelope Bilayer
- Nucleocapsid protein
- RNA (single strand)
- M-protein (membrane) and E-protein (envelope)
What are the current variants of concern (VOC)?
None
What are the current variants under monitoring (VUM)?
Anything containing the F456L spike mutation
What are the current variants being monitored (VBM)?
Omicron
Alpha
Beta
Gamma
What is the reproductive rate (R0)?
How many individuals a virus can be passed on to from 1 infected individual
What is the series interval (Si)?
The time it takes (in days) to pass on a virus to another individual
What are the 4 modes of transmission for COVID?
- Respiratory droplet
- Fomite - depends on surface
- Fecal-oral
- Vertical transmission
How long can COVID last on surfaces (as fomites)?
Copper + latex = 8 hours
Wood + glass = 5 days
How long can COVID respiratory droplets stay in the air?
Up to 3 hours
What percent of COVID transmission occurs through vertical transmission?
~3% occurs during later stages of pregnancy and in breastfeeding
What 4 risk factors increase risk of COVID-19 infection or mortality
Cardiovascular disease
Lung disease
Diabetes
Immunosuppression or cancer
What 3 elevated lab values would indicate increased risk of mortality?
- D-dimer
- Ferratin
- CK-MB
What are the 3 phases of COVIDs disease course?
Stage 1 - viral response
Stage 2 - pulmonary phase
Stage 3 - hyper inflammatory phase
Explain the viral response of COVIDs disease course:
The viral response includes the incubation and infectious periods
- person shows mild symptoms
- is contagious
Explain the pulmonary phase of COVIDs disease course:
- when the adaptive immune response occurs
- person experiences hypoxia and dyspnea
List the events of the hyper inflammation phase in COVIDs disease course (4)
- Disseminated intravascular coagulation
- cytokine storm
- ARDS
- multi-system organ failure
What are the target cells and target tissue of COVID?
Target cells: any cells that have an ACE2 receptor
Lungs are the main target area - alveoli have type 2 pneumocytes with ACE2 receptors
**other cells also have ACE2 receptors, which is why COVID produces a variety of symptoms
What is the co-receptor that COVID uses?
Transmembrane protease serine 2 (TMPRSS2)
Explain the cytokine storm
AKA Cytokine release syndrome
Whole bunch of WBC are activated through air but they then release a bunch of inflammatory cytokines which then activates more immune cells
– creates positive feedback loop
What 4 WBC are part of the cytokine storm?
Macrophages
Lymphocytes
Dendritic cells
Monocytes
What are the 4 effects of the cytokine storm?
- Act on vascular endothelium (VCAMS)
- Activate neutrophils
- Impaired coagulation
- Increase in chemical mediators