Current Topics

Question 1

Question 2

3 prime examples of vaccination working well

Answer 2

Question 3

Problems with vaccines

Answer 3

* protection not complete (can still become infected and develop clinical signs of disease)

* Adverse events associated– generally mild (swlling, fever, aches, pain); severe side effects (allergic reaction, vaccine associated feline sarcomas)

* Many vaccines require a level of “herd immunity” for them to be effective- difficult to explain to people with no scientific background

* Some vaccines are expensive (e.g. Hendra virus vaccines $100-200 per horse, twice per year)– veterinary vaccines not subsidized by the government

Question 4

Why are anti-vaccination sentiments re-emerging? Common themes with anti-vaccination?

Answer 4

People have never seen the diseases, if vaccination level drops below 75%, high risk of becoming ill

* social media facilitating dissemination of information (misinformation)

* safety concerns- toxins/ poisons, causing Autism

* concerns for effectiveness

* conspiracy theories– “big pharma”

* moral objections- against animal testing

* natural “alternatives”- homeopathy

Question 5

What were the consequences of the Wakefield study?

Answer 5

Question 6

Dangers associated with anti-vaccination sentiments?

Answer 6

Question 7

Example of a vaccine concern in poultry?

Answer 7

Question 9

What is influenza? Who does type A infect? Type B/C?

Answer 9

* An acute respiratory illness resulting from infection

* different strains have different severities

Question 10

What does HA do? NA?

Answer 10

* HA- attach

NA- release

Question 11

Where do influena A viruses come from?

Answer 11

* water birds- common

* all the ones in black have infected humans and can sustain themselves human to human (PANDEMIC)

* the ones in red- infected humans and caused severe disease but cannot transmit human to human

Question 12

Influenza pandemics

Answer 12

Cytokine storms can cause the major deaths in a young population

Question 13

Influenza epidemics

Answer 13

Question 14

Important aspects of influenza that allow it to persist in the human population?

Answer 14

* can’t proof read and genetic segments

* Antigenic shift (pandemic)- avian and human virus able to infect the same cell–> when they replicate– they can mix genome segments

* Antigenic drift (epidemic- seasonal variation)- acquistion of point mutations over time

Question 15

Impact of 1918 Spanish Flu pandemic (H1N1)?

Answer 15

* many died from bacterial infections

Question 16

Why are we currently concerned about a influenza pandemic #1?

Answer 16

Question 17

Why are we currently concerned about a influenza pandemic number 2?

Answer 17

Question 18

What happened in 2009 with influenza?

Answer 18

Question 19

How would you slow a pandemic?

Answer 19

Question 20

How do the antiviral drugs work?

Answer 20

* M2 channel blockers- stop virus from getting out and replicating

* NA inhibitors- block the process of the virus getting out of the cell

Question 21

Problems associated with using antiviral drugs to treat influenza infections?

Answer 21

Question 22

Seasonal influenza vaccines

Answer 22

Dead viruses- cannot get influenza but can get a reaction

Question 23

Problems with pandemic vaccination

Answer 23

* WHO tries to reach a consensus for what vaccine should have

Question 24

Role of the Global Influenza Surveillance and Response System (GISRS)

Answer 24

Question 25

What happens when a sample is received by the WHO Collaborating Centers (CC)?

Answer 25

Question 26

How are the samples analyzed when they are received at a WHO CC?

Answer 26

Question 27

How does influenza replicate?

Answer 27

Question 28

How is influenza sampled?

Answer 28

Question 29

How is influenza detected?

Answer 29

Question 30

What Family is Ebola virus in? What is the mortality?

Answer 30

Filoviridae Mortality 50-90%

Question 31

Where do most African Ebola Outbreaks occur since 1976?

Answer 31

Question 32

Ebola virus ecology?

Answer 32

Reservoir host- bats \* means of local enzootic (endemic) maintenance and transmission of the virus within bat populations is unknown \* Epizootics appear sporadically, producing high mortalities with non-human primates and duikers and may precede humans outbreaks \*\* Reston virus is the excepton as it does not produce detectable disease in humans \*\* HUman to human transmission is the predominant feature in epidemics following initial human infection through contact with infected bat or other wild animal \* Ebolaviruses: Ebola Virus, Sudan Virus, Tai Forest Virus, Bundibugyo virus, Reston virus (non-human)

Question 33

What is the incubation of Ebola? Where is it most infectious at peak symptoms/death? How long can it persist in semen?

Answer 33

\* Incubation 4-10 days- onset abrupt \* 10- 21 are peak symptoms/death \* Clinical recovery 20- 30 days \* Potential sexual transmission up to 82 days post recovery = 112 days

Question 34

Ebola virus transmission

Answer 34

\* Entry through mucous membranes and broken skin \* High titres in blood \* infectious dose 1-10 particles \* Found in many body fluids and excreta without blood contamination: saliva, tears, breast milk, faeces, semen, and sometimes urine \* Maximum days duration of RNA detection examples: blood (21), semen (101), conjunctival swabs (22), urine (23), rectal swabs (21) \* Propagation generally involves intimate contact: secondary attack rates 10-15% \* Transmission risk increases with contact \* 1976 Sudan e.g. Family members sharing sleeping quarters 23%, Active nursing care 81% transmission

Question 35

Why is Ebola classified as a level 4 agent?

Answer 35

Basis of high CFR 50-90% and absence of therapeutics or vaccines

Question 36

What is R naught? What is Ebolas?

Answer 36

The number of cases one case generates on average over teh course of its infectious period Ebola = 1/2

Question 37

What are the 7 basic rules of biosafety?

Answer 37

\* Do not mouth pipette \* manipulate infectious fluids carefully to avoid spills and production of aerosols \* restrict the use of needles and syringes, use only if there is no alternative \* use PPE \* Wash hands following all laboratory activities, following removal of gloves and immediately after contact with infectious materials \* Decontaminate work surfaces before and after use, and immediately after spills \* Do not eat, drink, store food, smoke, take medications in teh laboratory

Question 38

Steps in PC4 lab

Answer 38