A lot of speculation on this thread. There are no long term studies of the longevity of immunity. The two vaccines in the USA (mRNA vaccines) are focused on the spike protein, and not a common type of vaccination. Corona virus mutates rapidly and we don't know how long the current vaccines will confer immunity, or if it will work well on mutations. How can someone say it is better to get a the second or booster vaccination in 5 to 6 months? No one has studied this, with these vaccines and the corvid 19 virus. It is very possible that a "booster" or even a second type of vaccine may be better in the future.
There are some documented cases of re-infection and some have been more serious (including death) than the fist case. Some have been mutations of the original virus, some appear to be the same virus genetic variant.
The reality is that you will probably not get "herd immunity" within a year in the USA, because of those who will refuse, or cannot take the vaccination. Although the number of persons in the polls who will refuse is in the 15 to 20% (down from earlier this year), a recent Kaiser study suggest that 29% of health care workers may reject taking the vaccine. That is disturbing to me.
We plan to keep masking and social distance for at least the next year.
There are a large number of people who refuse to wear masks. there are even establishments which have signs "No Masks Allowed" and will not allow anyone to enter who is wearing a mask. (I found this out as I talked to cousins in Idaho and Colorado.). Even in cities who have "masks required" there has been little enforcement.
From: FDA Briefing Document Pfizer-BioNTech COVID-19 Vaccine:
Vaccine efficacy for the primary endpoint against confirmed COVID-19 occurring at least 7 days after the second dose was 95.0% with 8 COVID-19 cases in the vaccine group compared to 162 COVID-19 cases in the placebo group.
Only 3% of participants had evidence of prior infection at study enrollment, and additional analyses showed that very few COVID-19 cases occurred in these participants over the course of the entire study (9 in the placebo group and 10 in the BNT162b2 group, only 1 of which occurred 7 days or more after completion of the vaccination regimen – data not shown). ..... While limited, these data do suggest that previously infected individuals can be at risk of COVID-19 (i.e., reinfection) and could benefit from vaccination.
Based on the cumulative incidence curve for the all-available efficacy population after Dose 1, COVID-19 disease onset appears to occur similarly for both BNT162b2 and placebo groups until approximately 14 days after Dose 1, at which time point, the curves diverge, with more cases accumulating in the placebo group than in the BNT162b2 group, and there does not appear to be evidence of waning protection during the follow-up time of approximately 2 months following the second dose that is being evaluated at this point in time.
The graph would not transfer, but the incidence of covid 19 infections were the same between the Placebo and the vaccinated group until about 14 days after the first dose. At this point there is 95% protection from the vaccine over the 2 months periods studied. There is absolutely no information at this time, with this vaccine that the second dose would be better given months later.
During and after the SARs Infections in 2009, there were papers written on what type of vaccines could and should have been tried. These included: inactivated vaccines, virally and bacterially vectored vaccines, recombinant protein and DNA vaccines, as well as the use of attenuated virus vaccines.
Here is a link to a CDC article about current types of vaccines which are in the pipeline.
Be safe!
