Polio ARS Flashcards
March of Dimes established under which president?
Roosevelt in 1938
Definition of Eradication
Complete elimination of a microorganism from natural environments such that vaccination is no longer necessary to protect individuals from infection/disease
Which two organisms have been eradicated to date?
Smallpox
Rinderpest
Who still receives smallpox vaccines?
US military personnel
Can you eradicate tetanus organism and rabies?
no - too many animal hosts for rabies and its in the dirt for tetanus…
Rationale for poliovirus eradication
- Only infects humans (no non-human reservoirs)
- Effective, inexpensive vaccine is available
- Mucosal immunity from OPV blocks transmission
- Can only survive for days to weeks outside human hosts
Why does a cheesecloth filter work to make water safe from Guinea Worms?
It only needs to be fine enough to keep the water fleas out of the water.
How many years of national immunization days does it take to eradicate polio from a region?
5 years
How many doses of OPV used each year since 2000?
1-2 billion doses
Bivalent OPV induces protection against __ and __ than the trivalent OPV
Serotype 1 & 3
This happens because virus using the same type of cells to replicate - they are competing. If you pull the Type 2 out of the vaccine, then there is only one other serotype to compete with, so you get better overall antigen production (coverage).l
Use of bOPV has decreased immunity to which serotype relative to tOPV?
Serotype 2 - because you dont even try to vaccinate against this with bOPV.
Which OPV strains revert?
All - 1, 2, and 3
If you have a VDPV with 3% nucleotide variation from its corresponding OPV, how long has it been circulating?
Vaccine derived strains are error prone, primarily in wobble positions. Accumulate at 1% per year, so 3% changes = 3 years of uninterrupted person-to-person replication
