Microbiology E (Virology & Immunology) Flashcards
Which of the following is typically the first line of defense against viral infections?
a. Adaptive immunity
b.Innate immunity
c. Antibodies
d.T cells
Innate immunity
Which cells are primarily responsible for producing interferon during a
viral infection?
a. B cells
b.T cells
c. Activated antigen presenting cells
d.Neutrophils
Activated antigen presenting cells
Which of the following is NOT a characteristic of the adaptive immune
response to viral infections?
a.Specificity
b.Memory
c. Immediate response
d.Diversity
Immediate response
Which type of T cell is primarily responsible for directly killing virus-infected cells?
a.CD4+ T helper cells
b.CD8+ cytotoxic T cells
c.Regulatory T cells
d.Memory T cells
CD8+ cytotoxic T cells
What is the primary function of antibodies in viral infections?
a. Directly kill viruses
b.Neutralize viruses
c. Present antigens
d.Produce interferon
Neutralize viruses
Which of the following is a key feature of immunological memory in viral infections?
a.Slower response to subsequent infections
b.Reduced antibody production
c. Faster and stronger response to subsequent infections
d.Decreased T cell activation
Faster and stronger response to subsequent infections
Which of the following best describes virus-specific IgM antibodies?
a.They are produced late in the immune response
b.They indicate long-term immunity
c.They are typically the first antibody class produced in a
primary infection
d.They can cross the placenta
They are typically the first antibody class produced in a primary infection
What is the main mechanism by which fever helps combat viral infections?
a. It directly kills viruses
b.It increases antibody production
c. It inhibits viral replication
d.It enhances T cell proliferation
It inhibits viral replication
Which of the following is NOT a common mechanism of viral evasion of the immune response?
a. Antigenic drift
b.Latency
c. Increasing host cell MHC expression
d.Cell to cell adhesion
Increasing host cell MHC expression
What is the role of CD4+ T helper cells in antiviral immunity?
a. Directly kill infected cells
b.Produce antibodies
c. Help activate other immune cells
d.Produce interferon
Help activate other immune cells
What is meant by “cytokine storm” in viral infections?
a. The rapid mutation of viral cytokine genes
b.An excessive immune response leading to tissue damage
c. The production of antiviral cytokines by infected cells
d.The inhibition of cytokine production by the virus
An excessive immune response leading to tissue damage
What is the primary function of viral neuraminidase?
a. To facilitate viral entry into cells
b.To aid in viral genome replication
c. To cleave sialic acid residues, allowing viral release
d.To inhibit host cell protein synthesis
To cleave sialic acid residues, allowing viral release
What is the role of viral proteases in pathogenesis?
a. To degrade host cell proteins
b.To cleave viral polyproteins
c. To evade the immune system
d.To induce cell fusion
To cleave viral polyproteins
Which of the following best describes viral latency?
a. A period of rapid viral replication
b.The virus’s ability to infect multiple species
c. A dormant state with minimal viral gene expression
d.The time between infection and symptom onset
A dormant state with minimal viral gene expression
What is the primary purpose of virus-induced cell fusion?
a. To evade the immune system
b.To spread infection to neighboring cells
c. To increase viral replication rate
d.To induce apoptosis
To spread infection to neighboring cells
Which of the following is an example of viral cytopathic effect?
a. Production of interferon
b.Formation of inclusion bodies
c. Activation of T cells
d.Production of antibodies
Formation of inclusion bodies
What is meant by viral persistence?
a. The ability of a virus to mutate rapidly
b.The tendency of a virus to cause chronic infections
c. The speed at which a virus replicates
d.The virus’s resistance to antiviral drugs
The tendency of a virus to cause chronic infections
What is viral shedding?
a. The process of a virus losing its envelope
b.The release of viral particles from an infected host
c. The breakdown of viral particles by the immune system
d.The mutation of viral genes
The release of viral particles from an infected host
Which of the following best describes viral tropism?
a. The ability of a virus to mutate
b.The tendency of a virus to infect specific cell types or
tissues
c. The rate at which a virus replicates
d.The immune response to a virus
The tendency of a virus to infect specific cell types or
tissues
Which of the following best describes viral immune evasion?
a. The ability of a virus to rapidly mutate
b.Strategies used by viruses to avoid detection or elimination by the immune system
c. The process of viral shedding
d.The virus’s ability to infect immune cells
Strategies used by viruses to avoid detection or elimination by the immune system
Which of the following is the preferred method for collecting respiratory virus specimens?
a. Blood draw
b.Nasopharyngeal swab
c. Urine sample
d.Skin scraping
Nasopharyngeal swab
When collecting tissue samples for virus isolation, what is the recommended sample size?
a. 1-2 mm3
b.5-10 mm3
c. 20-30 mm3
d.50-100 mm3
5-10 mm3
Which of the following is NOT a suitable method for long-term storage of viral specimens?
a.Ultra-low temperature freezer (-70°C or lower)
b.Liquid nitrogen
c. Lyophilization (freeze-drying)
d.Refrigerator (2-8°C)
Refrigerator (2-8°C)
What is the primary purpose of adding transport medium to viral swab specimens?
a.To lyse host cells
b.To maintain virus viability
c.To inactivate the virus
d.To concentrate viral particles
To maintain virus viability
Which technique is commonly used for the initial purification of viruses from complex biological samples?
a.Ultracentrifugation
b.Dialysis
c.Electrophoresis
d.Mass spectrometry
Ultracentrifugation
What is the purpose of using a cryoprotectant when freezing viral specimens?
a.To prevent bacterial contamination
b.To maintain pH balance
c.To reduce ice crystal formation
d.To inactivate host cell enzymes
To reduce ice crystal formation
Which of the following is a key advantage of using cell culture for virus isolation?
a.Rapid results
b.Ability to detect non-viable viruses
c. High sensitivity for low viral loads
d.Isolation of infectious virus particles
Isolation of infectious virus particles
What is the primary purpose of using a negative stain in electron microscopy for viral characterization?
a.To increase viral particle size
b.To enhance contrast between the virus and background
c.To selectively stain specific viral proteins
d.To inactivate the virus
To enhance contrast between the virus and background
Which of the following techniques is used to determine the size and shape of viral particles?
a.Western blot
b.ELISA
c.Transmission electron microscopy
d.Flow cytometry
Transmission electron microscopy
Which of the following is the most appropriate method for collecting vesicular fluid from skin lesions suspected of viral infection?
a.Cotton swab
b.Sterile needle and syringe
c.Skin scraping
d.Biopsy punch
Sterile needle and syringe
Which of the following diagnostic methods is most appropriate for rapid detection of an emerging viral outbreak?
a.Virus isolation in cell culture
b.Electron microscopy
c.Real-time RT-PCR
d.Serological testing
Real-time RT-PCR
In developing a vaccine against a novel respiratory virus, which type
of vaccine is likely to elicit the strongest mucosal immunity?
a. Intramuscular inactivated vaccine
b.Oral live attenuated vaccine
c.Subcutaneous subunit vaccine
d.Intramuscular DNA vaccine
Oral live attenuated vaccine
Which control strategy would be most effective in preventing the
spread of a mosquito-borne viral disease in an urban area?
a.Mass vaccination
b.Vector control measures
c.Quarantine of infected individuals
d.Antiviral treatment of all residents
Vector control measures
What is the most important factor to consider when implementing a
ring vaccination strategy to control a viral outbreak?
a.The incubation period of the virus
b.The cost of the vaccine
c.The size of the affected population
d.The route of vaccine administration
The incubation period of the virus
In developing a multivalent vaccine against several strains of a virus,
what is the primary concern?
a. Increased production costs
b.Potential for antigenic interference
c. Longer time for immunity development
d.Higher risk of adverse reactions
Potential for antigenic interference
Which diagnostic approach would be most appropriate for large-scale screening of a population for past exposure to a specific virus?
a. Viral culture
b.PCR testing
c. Serological testing for IgG antibodies
d.Antigen detection assays
Serological testing for IgG antibodies
Which of the following strategies would be most effective in preventing nosocomial spread of a respiratory virus?
a. UV light disinfection of air
b.Prophylactic antiviral treatment for all patients
c. Strict hand hygiene and use of personal protective equipment
d.Daily screening of all hospital staff
Strict hand hygiene and use of personal protective equipment
In developing a viral vector vaccine, what is a key consideration to
ensure its effectiveness?
a. The vector should be derived from the target pathogen
b.The vector should not generate neutralizing antibodies
c. The vector should replicate rapidly in the host
d.The vector should cause mild disease symptoms
The vector should not generate neutralizing antibodies
What is the primary purpose of implementing a heterologous prime-
boost vaccination strategy?
a. To reduce vaccine production costs
b.To enhance immune response breadth and strength
c. To minimize adverse reactions
d.To shorten the time between doses
To enhance immune response breadth and strength
In designing a public health response to a new viral threat, which of the following should be prioritized first?
a. Development of a vaccine
b.Implementation of travel restrictions
c. Establishment of a robust surveillance system
d.Mass production of antivirals
Establishment of a robust surveillance system
Ten Saanen adult female goats were brought to the hospital due to arthritis, paralysis, mastitis and swelling of carpal joints, after 3 other kids from some of these does were found dead within 1-2 months
from the onset of clinical signs. What is the most possible causative agent for this case?
a. Caprine arthritis and encephalitis virus
b.Parapoxvirus orf
c. Lyssavirus rabies
d.Cache Valley virus
Caprine arthritis and encephalitis virus
Outbreaks of a disease with unexplained mortalities were reported in the Province of Rizal. Some pigs had high fever, diarrhea and purplish discoloration of the ears and abdomen. Outbreaks were observed mostly in
backyard farms who acquired new stocks from Farm X. Some of them confessed that they practice swill feeding. Based on the history presented, what is the case definition as stated in the ASF Contingency Plan of the Bureau of Animal Industry?
a. Suspect case
b.Probable case
c. Confirmed case
d.The disease is NOT ASF
Probable case
Aside from RT-PCR, ELISA can also be used to detect the presence of avian influenza antibodies in poultry for the purpose of local
transport or movement of poultry (except ducks) during outbreaks. All of these are registered Avian Influenza ELISA antibody test kits
EXCEPT?
a. IDEXX influenza A antibody test kit
b.BIOCHECK AI ELISA CK121
c. ProFLOK AIV Ab
d.AffiVET® Bird Flu/Avian Influenza Virus (H5N1) Antibody
Elisa Test Kit
AffiVET® Bird Flu/Avian Influenza Virus (H5N1) Antibody
Elisa Test Kit
An 8 month old buck was referred to the Veterinary Teaching hospital with the complaint of diarrhea, labored breathing, and oral lesions. The owner of the buck noticed lacrimation, watery diarrhea, ulcerative mouth lesions, and anorexia 5 days after
being off-fed and anorexic. The deworming and vaccination schedule was not up to date. Upon clinical examination, it was pyretic (400C) and had asphyxia. The mucus membrane of the oral cavity was pale with a putrid odor along with ulcerative lesions on
the lips and mouth. Along with ulcerative lesions, there was a mucopurulent nasal
discharge that leads to difficulty in breathing. All of these are possible causative agents for this case EXCEPT?
a. Peste des petits ruminants
b.Foot and mouth disease
c. Contagious ecthyma
d.Caprine arthritis and encephalitis
Caprine arthritis and encephalitis
You were consulted due to biting incident of a dog in your locality. Based on
the report, a dog has bitten another dog and its owner unprovoked. Both
dogs were apparently healthy but not vaccinated in the preceding 1 year.
You suspected rabies and advised that home quarantine should be done to the biting dog (suspect case; S) and the dog exposed to the rabies suspect
(probable case; P). How long should these dogs be quarantined to declare freedom from rabies?
a. S = 14 days; P = 14 days
b.S = 14 days; P = 6 months
c. S = 6 months; P = 6 months
d.S = 3 months; P = 6 months
S = 14 days; P = 6 months
An Holstein Friesian calf showed signs of increased salivation and nodules in most parts of the body. Upon physical examinations, the bull was lethargic and febrile with the
rectal body temperature of 40.4°C and 64 beats/min and 36 breaths/min heart rate and respiratory rates respectively. There were flare-up of small to large sized circumscribed nodules on different body parts. The nodules were also seen on the scrotum and hind legs. There was also swelling of both pre scapular and pre-femoral lymph nodes. All of these diseases can be suspected for this case EXCEPT?
a. Lumpy skin disease
b.Bovine herpes mammillitis
c. Foot and mouth disease
d.Bovine papular stomatitis
Foot and mouth disease
All of these viruses may be transmitted by bats EXCEPT
a.Nipah virus
b.Rabies lyssavirus
c.MERS-CoV
d.Classical swine fever virus
Classical swine fever virus
These cells are used by classical swine fever virus as Trojan horse for it to disseminate to other organs in the body.
a.neutrophils
b.monocytes
c. lymphocytes
d.basophils
Monocytes
What is the most common clinical sign in humans that tested positive to Orthoebolavirus restonense in the Philippines from 1989 to 2015?
a.Fever and paralysis
b.Petechial hemorrhages and bleeding
c. Diarrhea
d.None of these
None of these
What is the colloquial term for the pulmonary form of African horse sickness?
a.dikkop
b.dunkop
c. coloured
d.mulatto
Dunkop
