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A thread about vaccine efficacy & why we can’t get complacent
We have great vaccines: PFizer vaccine efficacy is at 95% 7 days after the second dose
Does that mean life goes back to normal once we reach a certain threshold vaccinated? Is vaccination ALONE enough?
In short:no
We have great vaccines: PFizer vaccine efficacy is at 95% 7 days after the second dose
Does that mean life goes back to normal once we reach a certain threshold vaccinated? Is vaccination ALONE enough?
In short:no
(2) I’m going to use the comparison with contraception as it’s one many people will be very familiar with
The combined oral contraceptive pill used correctly is very effective
But still, used correctly for a year 0.3% of women will get pregnant
The combined oral contraceptive pill used correctly is very effective
But still, used correctly for a year 0.3% of women will get pregnant
(3) our vaccines are 95% effective against symptomatic COVID-19
If they were an oral contraceptive we would be warning people of the risk of pregnancy if engaging in regular unprotected sex especially during fertile periods of the cycle
So how does that compare to covid?
If they were an oral contraceptive we would be warning people of the risk of pregnancy if engaging in regular unprotected sex especially during fertile periods of the cycle
So how does that compare to covid?
(4) well if it were pregnancy one was trying to avoid with a contraceptive that’s 95% effective we’d consider adding in a second contraceptive such as condoms especially at fertile periods in the cycle
This would reduce the risk of pregnancy but wouldn’t remove risk entirely
This would reduce the risk of pregnancy but wouldn’t remove risk entirely
(5) so when we have a vaccine that’s 95% effective that is a massive risk reduction almost but not quite as good as the COCP
So unlike the the COCP you wouldn’t recommend it in isolation
We need to keep the “barrier contraception” going
So unlike the the COCP you wouldn’t recommend it in isolation
We need to keep the “barrier contraception” going
(6) barrier methods for covid are:
social distancing,
regular hand washing
wearing our masks
This is especially important when community transmission is high: which is the equivalent of the fertile period of the menstrual cycle
social distancing,
regular hand washing
wearing our masks
This is especially important when community transmission is high: which is the equivalent of the fertile period of the menstrual cycle
(7) so in short vaccination is amazing risk reduction
But alone it is not enough
Especially when community transmission is high
We still need to wash our hands, keep our distance & wear our masks
But alone it is not enough
Especially when community transmission is high
We still need to wash our hands, keep our distance & wear our masks
(8) I must thank the amazing obstetricians & midwives that I work with for the fact that now I can convert almost everything into a “if this were pregnancy” comparator 
@drscorcoran @ProfFMcAuliffe @bergerie0709 @mairenihuigin @venitabroderick @Marybrosnan13 @lissaniskey
@drscorcoran @ProfFMcAuliffe @bergerie0709 @mairenihuigin @venitabroderick @Marybrosnan13 @lissaniskey
@Rheum2improve @DrZeroCraic @NiamhLQB @illonaduffy @DearbhailDibs @juneshannon @jenoconnell @louisemcsharry @SineadOCarroll @sineadgleeson @ZaraKing @newschambers @sharonlambert0 @ClionaNi @ritakj @marietcasey @russellnoirin @sjanemurf @SarahFitzWiMIN @Carrie_Thorpe1 @CcoHse
