Coronavirus Flashcards
What type of genetic material do coronaviruses have?
Single-stranded, positive-sense RNA
T/F. Coronaviruses are enveloped.
True
What’s the form of CoV’s nucleocapsid?
Helical
What are some key nonstructural proteins encoded by the coronavirus genome?
- RNA-dependent RNA polymerase
- Methyltransferase
- Helicase
Mention the major structural proteins.
- Hemagglutinin-esterase (HE)
- Surface glycoprotein/spike (S)
- Envelope protein (E)
- Membrane glycoprotein
- Nucleocapsid protein (N)
- Open reading frames (ORFs)
This protein lost receptor binding activity and esterase function, adapting to the human sialic acid receptor.
Hemagglutinin-esterase
Protein responsible for viral attachment, entry into host cells, and stimulation of neutralizing antibodies.
Surface glycoprotein/spike (S)
What is the function of additional open reading frames (ORFs) in coronaviruses?
Immune evasion
T/F. Coronaviruses are capable of genetic recombination if two CoVs co-infect the same cell.
True
Where does coronavirus development occur within the host cell?
Cytoplasm
Into which cellular structures do coronaviruses bud?
Cytoplasmic vesicles from pre-Golgi ER membranes
How are coronaviruses released from the host cell?
Via exocytic secretory pathway
Which viral protein is critical for the coronavirus release process?
Envelope protein (E)
Receptor for MERS CoV.
Dipeptidyl peptidase 4 (DPP4)
Receptor for SARS-CoV and SARS-CoV-2.
Angiotensin-converting enzyme 2 (ECA2)
What does CAR stand for in CAR coronavirus?
Common Acute Respiratory
Where have CAR CoV infections been detected?
Worldwide
In temperate climates, during which seasons are CAR CoV infections more common?
Winter and spring
Why is reinfection with CAR CoVs common?
Rapid decline of antibody levels
At what ages does CAR CoV infection occur most frequently?
All ages; most common in children
What does MERS stand for in MERS coronavirus?
Middle East Respiratory Syndrome
What was the primary mode of MERS transmission in its early years?
Nosocomial spread
What animal is a primary source of MERS-CoV infection in humans?
Camels
What does SARS stand for in SARS coronavirus?
Severe Acute Respiratory Syndrome
What were the primary transmission routes of SARS?
Droplet, airborne and contact transmission
Replication site for CAR CoV.
Ciliated and nonciliated epithelial cells
What is CAR CoV’s pathophysiology?
- Cell degeneration
- Release of chemokines and interleukins
CAR CoV symptoms are similar to…
Rhinovirus infection
Mention the two CAR CoV receptors.
- HCoC-229E
- NL63
What severe lung changes were found in an immunocompetent MERS patient ?
- Hyaline membrane formation
- Alveolar fibrin deposition
- Alveolar septal edema
Besides the lungs, what other systemic effects are associated with SARS?
Diarrhea, leukopenia, thrombocytopenia, and pal-lymphopenia
In which bodily fluids and organs has SARS-CoV been detected?
- Respiratory secretions, blood, stool, and urine
- Lung, spleen, lymph nodes, brain, kidney, and intestines
What severe pulmonary condition can SARS lead to?
Adult respiratory distress syndrome (ARDS)
What are the key pulmonary pathological findings in SARS?
- Hyaline membrane formation
- Lymphocytic and mononuclear cell infiltration
- Desquamation of pneumocytes in alveolar spaces
What type of cells found in SARS lun pathology have macrophage markers?
Giant cells
Where have viral particles, RNA, and protein been detected in SARS patients?
Type I and II pneumocytes
T/F. All four strains of CAR HCoVs cause serious respiratory illness
False
What respiratory illness can CAR CoVs cause in infants?
Pneumonia and bronchiolitis
What respiratory conditions can CAR CoVs cause in children and young adults?
- Otitis
- Exacerbations of asthma
What serious illness can CAR CoVs cause in healthy adults?
Pneumonia
What are the possible respiratory manifestations of CAR HCoVs in the elderly?
- Influenza-like illness
- Serious bronchitis
- Pneumonia
What is the spectrum of illness caused by MERS-CoV?
From subclinical disease to lethal pneumonia
Which groups are most severely or fatally affected by MERS-CoV?
Elderly with comorbidities
What are the common symptoms of MERS-CoV infection?
Fever, shortness of breath, cough, and diarrhea
What is the initial radiographic finding in MERS-CoV pneumonia?
Ground-glass appearence in the lung periphery
What radiographic finding in MERS-CoV is associated with a worse outcome?
Pleural effusion
What are the initial symptoms of SARS-CoV infection?
Fever and systemic influenza-like symptoms
These symptoms appear a few days to a week after initial symptoms.
Cough and dyspnea
What is the typical appearance of a chest radiograph in SARS-CoV patients?
Abnormal with scattered airspace opacification
Most common hematologic abnormality in SARS patients.
Lymphopenia
Neutrophil level that is associated with worse outcomes.
Neutrophilia
What muscle enzyme is often abnormal in SARS patients?
Creatine kinase
Which two liver-associated enzymes are frequently abnormal in SARS patients?
Lactate dehydrogenase and aspartate aminotransferase
Best approach for diagnosing CAR CoV.
RT-PCR
What are the primary serologic methods used to diagnose MERS-CoV?
- Enzyme-Linked Immunosorbent Assay (ELISA)
- Indirect Immunofluorescence Assays (IFA)
These are the most widely used and more sensitive method for detecting SARS-CoV.
RT-PCR
T/F. There’s no effective antiviral treatment for coronavirus; just supportive measures.
True
