Exam III: SARS-CoV-2 Student Presentations Flashcards
What is the death rate of COVID-19?
0.1%
Variant of Concern vs Variant of Interest
Concern = has a mutation that has increased virulence Interest = has a mutation that could increase virulence
What are the current variants of concern? (4)
Alpha
Beta
Gamma
Delta
What are current variants of interest? (5)
Eta Iota Kappa Lambda Mu
What are examples of spike mutations that lead to variants of concern? 1 for each variant
Alpha : Deletion of aa 69 and 70 of spike S1 fragment
Beta : E484K = evade antibodies
Gamma : H655Y = better escape
Delta : T478K = evade immune response
What is the receptor for SARS-CoV-2? What cells have the receptor?
ACE 2
Most; type II pneumocytes and alveolar macrophages
Where does infection of COVID often start?
In the airway
Primary mode of transmission is respiratory droplets
What is the cause of death from COVID-19?
Pneumonia is the primary underlying cause
Septic shock and multi-organ failure also
What does a molecular test look for? What is the mechanism of the test? When should you get a molecular test? Length of time? Accuracy?
Uses RT-PCR to detect the presence of the viral genome
Most accurate and widely used
Quick (2-4 hours) and accurate (99%)
What does an antigen test look for? What is the mechanism of the test? When should you get a molecular test? Length of time? Accuracy?
Detects viral proteins Use lateral flow assay (positive line catches viral proteins) While you have infection 15-30 min 50-80%
What does an antibody test look for? What is the mechanism of the test? When should you get a molecular test? Length of time? Accuracy?
Detects antibodies
Plate with virus > wash with antibody > add flourescence > does it have color = pos
Only used to see if you had a past infection
24-48 hours
98% accurate
What are the 3 types of vaccines being used against SARS-CoV-2?
- mRNA
- Viral Vector (DNA) Vaccines
- Inactivated Virus Vaccines
How do mRNA vaccines work?
ssRNA encoding spike protien surroinded by lipid nanoparticles > lipid layer fuses with cell membrane > RNA is translated in cytosol > viral spike protein is translated > cells present spike protein on membrane > antibodies are made agaisnt it
How do viral vector (DNA) vaccines work?
Inactivated adenovirus carries DNA encoding for spike protien > endocytosed > genome is replicated > spike protein is presented > antibodies are made agaisnt it
Creates stronger immune response because the vector stimulates immune system
How do inactivated virus vaccine work?
COVID envelope / nucelocapsid without the genome?
