MicroBioFinal - Influenza(Flu)

Question 1

disease agent

Answer 1

Influenza Virus: many types; H1NI (Swine Flu) is the one we’re focusing on now

• enveloped virus, 8 negative single stranded RNA
• 8 capsids with a piece of RNA and enzyme transcriptase in each
• has nametages - lollipops (N-spikes: neuraminidase) and cone shaped (H-spikes: hemagglutination)

Question 2

disease agent (H1N1 Swine Flu Replication)

Answer 2

1. attachment - likes epithelial cells of respiratory tract
2. penetration
3. uncoating
4. biosynthesis - turn -RNA into +RNA (+RNA makes proteins and some make -RNA)
5. assembly and maturation
6. relsease by budding - *high error rate = high mutation rate (1/10,000)

Question 3

what is a Reassortment?

Answer 3

Pandemic Flue happens b/c more than one virus invades one cell @ a time and this causes a different virus to be formed
***H1N1 is a quadruple reassortment, 2 swine versions, 1 human version, 1 avian (bird) version

Question 4

transmission

Answer 4

• direct contact by respiratory secretions, contact aersol, indirect fomite
• Upper respiratory tract disease (URT) and sometimes lower respiratory tract disease (LRT)

Question 5

symtoms

Answer 5

1. incubation: 1-4days (1 is most common)
2. disease - 3-5days; acute onset of fever, headache, chills, malaise, myalgia, cough/yellow sputum, sore throat
   *contagious 1 day prior to symptoms - 7 days after onset
   - can have lasting myalgia and malaise for weeks
   immune response = normal

Question 6

detection

Answer 6

• most dont go to hospital
• Neutralization Assay - doesnt tell you which type; to confirm you have flu; must confirm with RT-PCR and DNA fingerprint (rarely done b/c of bad science)

Question 7

treatment

Answer 7

NO CURE.

• ex: TamiFlu - Neuraminidase inhibitors (N. spikes)
• must treat within 48hrs inital onset

Question 8

prevention

Answer 8

• proper hygiene & avoid transmission: wash hands, disinfect
• vaccine availbale each year (70-90% effective); take 5 of the nametags of the one that might be most prevalent and then mature it in eggs)

Question 9

epidemiology

Answer 9

US

• dec 16%
• jan 24%
• feb 40%
• march 12%
• april 4%
• may 4%
• swine flue - 0.02%: same as regular flu