IASM 62 63: Virus Flashcards
Outline the 5 Periods of Infection 1. Incubation 2. Prodromal 3. Specific Illness 4. Decline 5. Convalescence Specify what each stage is for
- Incubation- Time between exposure and symptom appearance
- Prodromal- Non-specific symptoms start to occur
- Specific Illness- Characteristic features of the infectious disease start to occur
- Decline- Symptoms are resolving
- Convalescence- Recover from illness
Outline the 5 stages of infection
- _______- Time between exposure and symptom appearance
- _______- Non-specific symptoms start to occur
- ________- Characteristic features of the infectious disease start to occur
- _______- Symptoms are resolving
- ________- Recover from illness
- Incubation- Time between exposure and symptom appearance
- Prodromal- Non-specific symptoms start to occur
- Specific Illness- Characteristic features of the infectious disease start to occur
- Decline- Symptoms are resolving
- Convalescence- Recover from illness
What is meant by latent infection
The phase in which the pathogen is dormant or inactive
e.g. we can have acute viral infection => Latent infection => Reactivation
What is the definition of a virus
A non-living organism
Cannot reproduce by themselves
Contains genetic content
Virus Structure
The DNA or RNA is protected by a protein cover called ______.
It may have an additional covering called ________. (not for every virus)
Virus Structure
The DNA or RNA is protected by a protein cover called caspid.
It may have an additional covering called envelope. (not for every virus)
What does the following virus cause?
- Rhinovirus
- Poliovirus
- Varicella-zoster virus
- Hepatitis B Virus
- Mumps Virus
- HIV Virus
- Influenza Virus
What does the following virus cause?
- Rhinovirus: Common Cold
- Poliovirus: Polio 小兒麻痹症
- Varicella-zoster virus: Chickenpox
- Hepatitis B Virus: Hepatitis
- Mumps Virus: Mumps (Swollen region near the chin)
- HIV Virus: AIDS
- Influenza Virus: Influenza
Name the virus
- _______: Common Cold
- _____: Polio 小兒麻痹症
- ________: Chickenpox
- __________: Hepatitis
- __________: Mumps (Swollen region near the chin)
- _________: AIDS
- _________: Influenza
What does the following virus cause?
- Rhinovirus: Common Cold
- Poliovirus: Polio 小兒麻痹症
- Varicella-zoster virus: Chickenpox
- Hepatitis B Virus: Hepatitis
- Mumps Virus: Mumps (Swollen region near the chin)
- HIV Virus: AIDS
- Influenza Virus: Influenza
Virus Replication Cycle
- Attachment: ____________
- Penetration: ______________
- Uncoating: _____________
- Viral protein synthesis: _________________
- ___________________
- Virus Assembly: ________________
- Viral Release: ________________
Virus Replication Cycle
- Attachment: Virus attach to the surface of the cell
- Penetration: Virus penetrate through membrane of cell
- Uncoating: Virus uncoats and releases genetic materials
- Viral protein synthesis: Transcription and Translation to form proteins
- Viral DNA Replication
- Virus Assembly: Add protein coat to the viral genetic material
- Viral Release: Viral cell pass through cell membrane to the outside
What are the steps of formation of Viral Protein
- DNA Virus
- RNA Virus
- Retroviral (e.g. HIV) replication
What are the steps of formation of Viral Protein
- DNA Virus: Double strand DNA => Viral mRNA => Viral Protein
- RNA Virus: Negative Viral mRNA => Positive Viral mRNA (RNA Dependent RNA Polymerase) => Viral Protein
- Retroviral (e.g. HIV) replication: Viral RNA => Proviral DNA (reverse transcriptase) => Viral mRNA (transcriptase) => Viral Protein
What is the incubation period for viral infection
Time interval between entry of virus to the body and the commencement of the disease symptoms
To detect the virus, what methods can we use?
Electron microscopy
Viral antigen detection
PCR
How to amplify RNA virus by PCR
RNA viruses require reverse transcriptase to produce cDNA, then cDNA can be amplified by PCR
Virus Antibody Response
- Cells usually produce _______ first, then produce _______ (fill in with both kinds of antibodies)
- For recent infections, (1-3 months), we can detect the presence of ______ (antibody), but after 3 months, the level of this kind of antibody will drop
- Or, you can test the _______ (antibody) 10-14 days apart, there will be a _ fold increase in titre
Virus Antibody Response
- Cells usually produce IgM first, then produce IgG (fill in with both kinds of antibodies)
- For recent infections, (1-3 months), we can detect the presence of IgM (antibody), but after 3 months, the level of this kind of antibody will drop
- Or, you can test the IgG (antibody) 10-14 days apart, there will be a 4-fold increase in titre
What are prions
Misfolded protein that are infectious to induce misfolding of other proteins in the cells
Viruses causing Respiratory Tract Infection Adenovirus Coronavirus Influenza A, B MERS/ SARS-CoV-2 Respiratory Syncytial Virus (RSV) Rhinovirus
Arrange them in increasing likeliness to cause lower respiratory tract infection
Arrange them in increasing likeliness to cause lower respiratory tract infection
Rhinovirus Coronavirus Respiratory Syncytial Virus (RSV) Adenovirus Influenza A, B MERS/ SARS-CoV-2
