With the effectiveness of the 1st pfizer dose being 90% after Day 7 and the reported side effects being much worse after dose 2, why is the second dose emphasized so much? I know the effectiveness goes up to 95%, but what else? Longer protection?
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Is the 2nd dose really needed?
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Last: 3 yr ago by OldArmy71
Where are you seeing 90% in 7 days for the first dose? That doesn't sound right.
Username checks out.
1st dose has closer to 50% efficacy
The longer-term immunity demonstrated in the studies were in people who got two doses. There was not a statistically significant subgroup who only got one dose.
The data suggesting immunity after one dose was extrapolated from the study and was not the purpose of the study.
Right now, the best bet for the best protection is two doses. The side effects of the second dose are incredibly manageable if you even have side effects. I could have worked through them easily.
The data suggesting immunity after one dose was extrapolated from the study and was not the purpose of the study.
Right now, the best bet for the best protection is two doses. The side effects of the second dose are incredibly manageable if you even have side effects. I could have worked through them easily.
90% is correct and confirmed by several MDs on here. The original number reported is 54% however that was counting those who were infected the first week after receiving the first dose, which you wouldn't expect a immunity yet as antibodies take time to build up. Ill try to find the link to the study....
I Am A Critic said:
Where are you seeing 90% in 7 days for the first dose? That doesn't sound right.
One of the charts released with the Pfizer study indicated a significant separation from the placebo group at about day 10 from the date of first dose. Essentially, 90% of the people who got the first dose and got to around day 10 or so post 1st dose without an infection did not get sick later on. So there is likely some benefit, but we don't know how long lasting the benefit is with just one dose.
Again, would caution about reading too much into it as the vast majority of those people went on to receive a second dose. For all we know the benefit from the first of us could wear off within a month.
https://www.bmj.com/content/372/bmj.n18
"How effective is just one dose?
A paper published in the New England Journal of Medicine stated that the efficacy of the Pfizer-BioNTech vaccine was 52.4% between the first and second dose (spaced 21 days apart).5 However, in its "green book" Public Health England said that during the phase III trial most of the vaccine failures were in the days immediately after the first dose, indicating that the short term protection starts around day 10.6 Looking at the data from day 15 to 21, it calculated that the efficacy against symptomatic covid-19 was around 89%"
"How effective is just one dose?
A paper published in the New England Journal of Medicine stated that the efficacy of the Pfizer-BioNTech vaccine was 52.4% between the first and second dose (spaced 21 days apart).5 However, in its "green book" Public Health England said that during the phase III trial most of the vaccine failures were in the days immediately after the first dose, indicating that the short term protection starts around day 10.6 Looking at the data from day 15 to 21, it calculated that the efficacy against symptomatic covid-19 was around 89%"
Depends on what you mean by "needed"
The original bar for emergency authorization was 50%. Obviously a single shot is better than that.
On the other hand we run clinical trials because sometimes in science things that seem obvious are wrong.
Also, at this point getting people their second shot isn't the problem. There are 20 million first doses we can't get into arms because the logistics are complex and stupid.
The original bar for emergency authorization was 50%. Obviously a single shot is better than that.
On the other hand we run clinical trials because sometimes in science things that seem obvious are wrong.
Also, at this point getting people their second shot isn't the problem. There are 20 million first doses we can't get into arms because the logistics are complex and stupid.
Because that is the only way it has been studied. No one knows how long the vaccine will last.
This is the correct interpretation. You have to be exceeding careful reading findings into studies that the studies were not desiged to test. The study was not designed to test single dose immunity, so we shouldn't be basing any major decisions on a post-hoc subanalysis. At best those findings would be fuel for a new study dedicated to looking at single dose immunity. However, at this point that seems like a waste of time and resources better spent following the proven protocol we already have.Cactus Jack said:
The longer-term immunity demonstrated in the studies were in people who got two doses. There was not a statistically significant subgroup who only got one dose.
The data suggesting immunity after one dose was extrapolated from the study and was not the purpose of the study.
Right now, the best bet for the best protection is two doses. The side effects of the second dose are incredibly manageable if you even have side effects. I could have worked through them easily.
No material on this site is intended to be a substitute for professional medical advice, diagnosis or treatment. See full Medical Disclaimer.
I can't comprehend why a lay person would think they get the science/statistics better than the vaccine mfg's and FDA folks who approved it.
I do think we shouldnt just sit on doses for a 3-4 weeks like we have been. As long as we are receiving a reliable rate of new doses then we shouldn't be that careful. However I do think we need to do the tested vaccination schedule. Aggressively push to get the first dose into as many people as possible, prioritize 2nd dose at the required time above all other vaccinations.
So what is the bigger bottleneck right now? Production or distribution?
It depends on where you are. If you're in NY, and the priority is felons/drug addicts, vs. elderly/immune compromised it's different vs. Texas in Denton County where the issue is availability.Squadron7 said:
So what is the bigger bottleneck right now? Production or distribution?
This is probably true globally.
The one or two shot debate reminds me of this
There's emerging evidence in nursing homes that the first dose of the vaccine doesn't appear all that effective on the 80+ crowd. The studies on the vaccine didn't enroll many of these folks.
Not surprising. The elderly tend to have attenuated vaccine responses. However, considering how many have gotten the vaccine, and the timeline of when they could've gotten it, I don't think we can form a conclusion on exactly how effective it is in that population just yet. Can you post a link to the evidence you're talking about though?
https://montrealgazette.com/news/local-news/maimonides-families-demand-second-vaccine-dose-for-elderly-parents/wcm/65e4ffce-51e0-4130-a0a0-1f842bf8ea3c/amp/?__twitter_impression=true
Obviously, this is anecdotal, but that's basically all we have at this point. Elderly patients weren't studied very significantly in the virus studies (though there may be very good reason for that).
Obviously, this is anecdotal, but that's basically all we have at this point. Elderly patients weren't studied very significantly in the virus studies (though there may be very good reason for that).
dunning-kruger in full effectnortex97 said:
I can't comprehend why a lay person would think they get the science/statistics better than the vaccine mfg's and FDA folks who approved it.
They also have ACE2 problems, which is the vector. It's not altogether shocking in that way.agforlife97 said:
There's emerging evidence in nursing homes that the first dose of the vaccine doesn't appear all that effective on the 80+ crowd. The studies on the vaccine didn't enroll many of these folks.
https://nypost.com/2021/01/19/nachman-ash-says-pfizers-first-dose-less-effective-than-indicated/
this should throw cold water on the UK strategy
this should throw cold water on the UK strategy
Quote:
Nachman Ash Israel's equivalent of Dr. Anthony Fauci said the protection offered by the first dose is "less effective than we had thought," Army Radio reported.
"Many people have been infected between the first and second injections of the vaccine," Ash said, adding that the protective effect appears "lower than [the data] presented by Pfizer."
The pharmaceutical giant has claimed that trials show it is roughly 52 percent effective around 12 days after receiving the first shot, the BBC reported.
But that level of protection rises to 95 percent around two weeks after the second dose.
It's unclear exactly how effective the shot has been for the more than 2 million Israelis who have already received the first dose.
Questions were raised about the vaccine's performance after health officials on Monday announced 10,000 new cases, the highest since the pandemic began.
None of the vaccine trials looked for asymptomatic cases. The endpoint was confirmed symptomatic Covid.
So it's totally possible that one shot protects you from disease but not from detectable infection. It's even possible that two shots do that. Which would be fine from a public health perspective, but an absolute **** show for trying to open things back up. Governments are kind of all in on caseload as the metric.
So it's totally possible that one shot protects you from disease but not from detectable infection. It's even possible that two shots do that. Which would be fine from a public health perspective, but an absolute **** show for trying to open things back up. Governments are kind of all in on caseload as the metric.
all eyes on the Israeli hospitalization numbers
https://www.theguardian.com/world/2021/jan/19/single-covid-vaccine-dose-in-israel-less-effective-than-we-hoped
https://www.theguardian.com/world/2021/jan/19/single-covid-vaccine-dose-in-israel-less-effective-than-we-hoped
if the first shot is at least helping prevent symptomatic severe courses, we should see that eminentlyQuote:
Already more than 2 million Israelis have had their first Pfizer shot, while 400,000 have had a second.
Amid warnings that 30% to 40% of the new infections were being driven by a Covid-19 variant first identified in the UK, the Israeli cabinet was meeting on Tuesday to consider tightening existing restrictions. Some analysts, however, have put the prevalence of the new variant at lower levels.
The cabinet had been warned by Ash that the new variant was set to become the main source of infections in Israel within weeks.
The new concern follows the release of data on Monday by Israel's health ministry recording 10,021 infections the previous day, with a positivity rate above the 10% mark for the first time in more than three months, suggesting widespread community transmission.
The rates of infection have undercut the sense of optimism that the Israeli prime minister, Benjamin Netanyahu, has tried to project around Israel's vaccination campaign, for which he has taken credit.
Are they only considering people infected between days 12 - 21 in Israel? Getting infected on the day after you got the shot should not be considered as we know that vaccine offers no protection until 10 days post vaccination at the earliest.cone said:
https://nypost.com/2021/01/19/nachman-ash-says-pfizers-first-dose-less-effective-than-indicated/
this should throw cold water on the UK strategyQuote:
Nachman Ash Israel's equivalent of Dr. Anthony Fauci said the protection offered by the first dose is "less effective than we had thought," Army Radio reported.
"Many people have been infected between the first and second injections of the vaccine," Ash said, adding that the protective effect appears "lower than [the data] presented by Pfizer."
The pharmaceutical giant has claimed that trials show it is roughly 52 percent effective around 12 days after receiving the first shot, the BBC reported.
But that level of protection rises to 95 percent around two weeks after the second dose.
It's unclear exactly how effective the shot has been for the more than 2 million Israelis who have already received the first dose.
Questions were raised about the vaccine's performance after health officials on Monday announced 10,000 new cases, the highest since the pandemic began.
Data out of Israel suggests the first dose of Pfizer isn't very effective at all but the second dose is 90+% effective.
We have 4 ER nurses that developed COVID after their 1st dose. They developed symptoms a few days after receiving their 1st dose which means that they contracted it prior to immunity. In the lay public's eyes, this would be seen as a vaccine failure, which of course it is not. I don't put a lot of weight in reports of vaccine failures without data to back it up. Also, keep in mind that even > 7 days after the 2nd dose of the Pfizer vaccine, there is still a 5% failure rate, so some vaccine failure is expected. We will have plenty of observational studies that will be coming out in the coming months regarding observed vaccine efficacy in the community. Until then, all these reports of vaccine failures are largely worthless and should be taken with a large grain of salt.
No material on this site is intended to be a substitute for professional medical advice, diagnosis or treatment. See full Medical Disclaimer.
proof of the pudding is in the eatingQuote:
Until then, all these reports of vaccine failures are largely worthless and should be taken with a large grain of salt.
we should see covid hospitalizations fall off a cliff in Israel within the next 2-4 weeks if as good as advertised
was hoping the first dose would show that as well, but not gangbusters so far
Never mind, misunderstoodcone said:proof of the pudding is in the eatingQuote:
Until then, all these reports of vaccine failures are largely worthless and should be taken with a large grain of salt.
we should see covid hospitalizations fall off a cliff in Israel within the next 2-4 weeks if as good as advertised
was hoping the first dose would show that as well, but not gangbusters so far
i thought the article said 2 million israelis had gotten the first dose and 400k had gotten the 2nd
so they're about 20-25% through the full population on the first dose and 4-5% fully vaccinated
with those vaccinations going predominantly to the higher risk higher age population
so you'd think you'd see some strong progress 5 weeks in, specifically in terms of hospitalizations, if the first shot worked to alleviate that impact
this isn't to throw cold water on the whole project, just to strongly question the 1 shot dose approach
personally, i won't feel reasonably protected until i get the well-described chills and fever from the second shot. everyone should want that.
so they're about 20-25% through the full population on the first dose and 4-5% fully vaccinated
with those vaccinations going predominantly to the higher risk higher age population
so you'd think you'd see some strong progress 5 weeks in, specifically in terms of hospitalizations, if the first shot worked to alleviate that impact
this isn't to throw cold water on the whole project, just to strongly question the 1 shot dose approach
personally, i won't feel reasonably protected until i get the well-described chills and fever from the second shot. everyone should want that.
Sorry, I didn't realize you meant Israel. You are right that hopefully they start to see significant progress in the next month or two.cone said:
i thought the article said 2 million israelis had gotten the first dose and 400k had gotten the 2nd
so they're about 20-25% through the full population on the first dose and 4-5% fully vaccinated
with those vaccinations going predominantly to the higher risk higher age population
so you'd think you'd see some strong progress 5 weeks in, specifically in terms of hospitalizations, if the first shot worked to alleviate that impact
this isn't to throw cold water on the whole project, just to strongly question the 1 shot dose approach
personally, i won't feel reasonably protected until i get the well-described chills and fever from the second shot. everyone should want that.
Can someone give me a brief summary of those charts about Israel?