[BostonCard]

While we're on the subject of vaccine efficacy and we have a lot of experts in our midst, can anyone confirm or debunk the following:

I've been told/read that the flu shot loses its efficacy over time, and so if you are most worried about a peak flu season in Jan/Feb, you may want to wait and get the flu jab in November so that its peak efficacy overlaps with peak flu season. Is that total nonsense? For that reason, I've typically waited to get the flu shot until later in the fall, but if there's truly zero benefit to waiting, I'll take care of this now while COVID-19 case counts are lower in my community. 

Thanks!

https://www.cdc.gov/mmwr/preview/mmwrhtm...enzaSeason

There may be something to that...

Antibody levels induced by vaccine decline over the months after vaccination (99,352–354). Although a 2008 literature review found no clear evidence of more rapid decline among the elderly (105), a 2010 study noted significant decline in titers 6 months postvaccination among persons aged ≥65 years (though titers still met European Medicines Agency levels considered adequate for protection) (354). More recently, some investigators have estimated vaccine effectiveness over the course of a season, as a function of time since vaccination. A case-control study conducted in Navarre, Spain, during the 2011–12 season revealed a decline in vaccine effectiveness from 61% (95% CI = 5–84) in the first 100 days postvaccination to 42% (95% CI = -39–75) for 100–119 days postvaccination and to -35% (95% CI = -211–41) thereafter. This decline primarily affected persons aged ≥65 years, among whom vaccine effectiveness declined from 85% (95% CI = -8–98) to 24% (95% CI = -224–82) to -208 (95% CI = -1,563–43) over these intervals.

That being said, the efficacy of the vaccine is 0 when you don’t get it.  So they advise the following:

While delaying vaccination until later in the season might permit greater immunity later in the season, such deferral might result in missed opportunities to vaccinate, as well as difficulties in vaccinating a population within a more constrained time period. Community vaccination programs should balance maximizing likelihood of persistence of vaccine-induced protection through the season with avoiding missed opportunities to vaccinate or vaccinating after influenza circulation occurs.

BC

[BostonCard]

While we're on the subject of vaccine efficacy and we have a lot of experts in our midst, can anyone confirm or debunk the following:

I've been told/read that the flu shot loses its efficacy over time, and so if you are most worried about a peak flu season in Jan/Feb, you may want to wait and get the flu jab in November so that its peak efficacy overlaps with peak flu season. Is that total nonsense? For that reason, I've typically waited to get the flu shot until later in the fall, but if there's truly zero benefit to waiting, I'll take care of this now while COVID-19 case counts are lower in my community. 

Thanks!

https://www.cdc.gov/mmwr/preview/mmwrhtm...enzaSeason

There may be something to that...

Antibody levels induced by vaccine decline over the months after vaccination (99,352–354). Although a 2008 literature review found no clear evidence of more rapid decline among the elderly (105), a 2010 study noted significant decline in titers 6 months postvaccination among persons aged ≥65 years (though titers still met European Medicines Agency levels considered adequate for protection) (354). More recently, some investigators have estimated vaccine effectiveness over the course of a season, as a function of time since vaccination. A case-control study conducted in Navarre, Spain, during the 2011–12 season revealed a decline in vaccine effectiveness from 61% (95% CI = 5–84) in the first 100 days postvaccination to 42% (95% CI = -39–75) for 100–119 days postvaccination and to -35% (95% CI = -211–41) thereafter. This decline primarily affected persons aged ≥65 years, among whom vaccine effectiveness declined from 85% (95% CI = -8–98) to 24% (95% CI = -224–82) to -208 (95% CI = -1,563–43) over these intervals.

That being said, the efficacy of the vaccine is 0 when you don’t get it.  So they advise the following:

While delaying vaccination until later in the season might permit greater immunity later in the season, such deferral might result in missed opportunities to vaccinate, as well as difficulties in vaccinating a population within a more constrained time period. Community vaccination programs should balance maximizing likelihood of persistence of vaccine-induced protection through the season with avoiding missed opportunities to vaccinate or vaccinating after influenza circulation occurs.

BC