Review Questions for Influenza Flashcards
(29 cards)
- In what type of environmental conditions does influenza virus survive best?
Virus survives better at low humidity (
- Can influenza virus survive outside the human body? What fomite surface does it survive the longest?
Touch surface with virus then touch mouth or nose
Survival on hard surfaces: 1 – 2 days
Survival on kleenex: 15 minutes
Survival on hands: 5 minutes
- When is typical flu season?
Late November April
- What family of viruses does influenza belong?
Orthomyxovirus
- What is the genome for influenza
RNA single strand virus
- What age group suffers the most deaths each year in the United States from influenza infection?
Greater than 90% are over 60 yrs old
- Name the two surface proteins on the envelope and give the purpose of each in the viral life cycle.
Hemagglutinin (H)
Attaches to host cell membrane receptor
Responsible for viral entrance into host cell
Neuraminidase (N)
Help penetrate mucus
Responsible for new viruses budding from infected cells
- How many subtypes exist for Hemagglutinin? Which ones have been isolated from humans?
16 subtypes
Six subtypes recovered from Humans: H1,H2,H3,H5,H7,H9
- How many subtypes exist for Neuraminidase? Which ones have been isolated from humans?
9 subtypes
Two subtypes recovered from Humans: N1, N2
- List the 3 types of human influenza: Type A,B orC
Answer the following questions based on the 3 types of Influenza.
a. Which type is included in the yearly human influenza vaccine?
b. Which one typically causes pandemics?
c. Which one does not cause epidemics?
d. Which on can circulate in other animals other than humans?
e. Wild birds are believed to be the primary reservoir for all subtypes.
f. The pig can serve as the melting pot for new strains for this type of influenza.
g. Causes mild respiratory illness and is not included in human vaccines
a. Which type is included in the yearly human influenza vaccine? A& B
b. Which one typically causes pandemics? A
c. Which one does not cause epidemics? C
d. Which on can circulate in other animals other than humans? A
e. Wild birds are believed to be the primary reservoir for all subtypes. A
f. The pig can serve as the melting pot for new strains for this type of influenza. A
g. Causes mild respiratory illness and is not included in human vaccines. C
- Name the 2 ways in which influenza can mutate: Antigenic Drift or Antientic Shift
Answer the following questions based on type of mutation.
a. Which one represents small mutational changes?
b. Which one represents a major muration?
c. Which one causes small changes continually over time?
d. Which one led to the creation of the Novel H1N1 2009 influenza strain?
e. Leads to a pandemic.
f. May result in new flu epidemic.
g. Rare event.
h. Can emerge from animal or human.
a. Which one represents small mutational changes? Antigenic Drift
b. Which one represents a major muration? Antientic Shift
c. Which one causes small changes continually over time? Antigenic Drift
d. Which one led to the creation of the Novel H1N1 2009 influenza strain? Antientic Shift
e. Leads to a pandemic. Antientic Shift
f. May result in new flu epidemic. Antigenic Drift
g. Rare event. Antientic Shift
h. Can emerge from animal or human. Antientic Shift
- Use the following influenza virus name to answer the questions: A/Hong Kong/1/68/(H3N2)
a. What part of the name represents the strain number?
b. Where did the first case of this virus occur?
c. What year was it isolated/
d. What was the Hemagglutinin subtype/
a. What part of the name represents the strain number? 1
b. Where did the first case of this virus occur? Hong Kong
c. What year was it isolated? 68
d. What was the Hemagglutinin subtype? H3N2
- If the ciliated mucosa is destroyed by influenza virus, will it normally grow back?
Yes
10 days to 2 months
- If the ciliated mucosa is destroyed by influenza virus, what secondary infection is most likely to infect the lower respiratory tract?
Pneumonia
- How is influenza transmitted?
Droplet Transmission Person-to-person within 6 ft Respiratory droplets, cough/sneeze Deposit on mouth or nose Contact Transmission Touch surface with virus then touch mouth or nose
- What are the clinical symptoms of influenza/
Incubation period: 1 – 4 days
Fever; often high (104oF)
Head-ache, fatigue, muscle ache
Sore throat, dry cough, runny/stuffy nose
8 days later
Viral shedding from infected cells stops
Acute phase over
Several Weeks Later
Dry cough
Fatigue
Weakness
- Which form of the vaccine is safest for an immune deficient patient?
Inactivated Vaccine
Fluzone
- Which form of the vaccine contains live material? Dead material?
Live material - Nasal Spray Flu vaccine - Flumist
Dead material - Inactivated Vaccine - Fluzone
- For maximum effectiveness when should antiviral medications begin for influenza patients?
Must start in 48 hours to be effective
- Which group of antiviral medications does not work for the H1N1 Novel virus? Why is this unusual (think of the Type of Influenza virus)?
M2 Inhibitors
M2 Inhibitors are used for type A strains except for the Novel H1N1 virus. It is unusual because it falls under the type A virus.
- Use the following influenza virus name to answer the questions: A/Hong Kong/1/68/(H3N2)
a. What part of the name represents the strain number?
b. Where did the first case of this virus occur?
c. What year was it isolated/
d. What was the Hemagglutinin subtype/
a. What part of the name represents the strain number? 1
b. Where did the first case of this virus occur?
c. What year was it isolated?
d. What was the Hemagglutinin subtype?
- If the ciliated mucosa is destroyed by influenza virus, will it normally grow back?
10 days – 2 months to restore ciliated epithelial cells
- If the ciliated mucosa is destroyed by influenza virus, what secondary infection is most likely to infect the lower respiratory tract?
Pneumonia
- How is influenza transmitted?
Droplet Transmission
Person-to-person within 6 ft
Respiratory droplets, cough/sneeze
Deposit on mouth or nose
Contact Transmission Touch surface with virus then touch mouth or nose Survival on hard surfaces: 1 – 2 days Survival on kleenex: 15 minutes Survival on hands: 5 minutes
