[HN Gopher] Repeated influenza vaccination effects might apply t...
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       Repeated influenza vaccination effects might apply to Covid-19
       vaccines
        
       Author : nradov
       Score  : 17 points
       Date   : 2022-05-03 19:57 UTC (3 hours ago)
        
 (HTM) web link (www.thelancet.com)
 (TXT) w3m dump (www.thelancet.com)
        
       | AftHurrahWinch wrote:
       | The bottom line is: "Data on influenza vaccines suggests that
       | repeated vaccinations in an individual might ultimately result in
       | a blunted immune response, declines in vaccine effectiveness, and
       | a possibly reduced duration of protection... ...The underlying
       | mechanisms through which previous vaccinations can affect the
       | effectiveness of subsequent vaccinations in an individual are
       | unclear, but two theories are widely discussed in the influenza
       | literature. "
       | 
       | The theories are: "...the antigenic distance hypothesis... the
       | blunting of influenza vaccine effectiveness by previous influenza
       | vaccination has been the most pronounced when the vaccine antigen
       | was unchanged, but an antigenically distinct virus became the
       | predominant circulating strain."
       | 
       | And: "Since vaccine-induced immunity blocks or reduces the risk
       | of infection, the theory asserts that the percentage of people
       | who are unvaccinated with presumably stronger infection-induced
       | immunity will increase over time. Thus, estimates of COVID-19
       | vaccine effectiveness will probably decline as the gap in immune
       | protection between people who are repeatedly vaccinated versus
       | those who are unvaccinated declines."
       | 
       | The first theory would apply in instances where the antigen
       | changes but the vaccine is not updated.
       | 
       | The second theory would apply if vaccinated people didn't also
       | acquire infection-induced immunity.
        
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       (page generated 2022-05-03 23:02 UTC)