Thread by @vipintukur

The new #MayoClinic study finds Vaccine Effectiveness (VE) of #Pfizer shot dropped to 42% against #Delta #SARSCoV2 infection (not against hospitalization & deaths). 1/

medrxiv.org/content/10.110…

Earlier unpublished reports from #Israel also indicated the same 2/

Few other recent studies have also placed the #VE of Pfizer mRNA vaccine between 40-60% against #SARSCoV2 infection/symptomatic disease but not against severe disease & deaths. Table by @EricTopol 3/

If we retrospectively analyze the performance of the two #Covid vaccines employed here in India, their performance against Delta (#Covishield VE 63·1% & #Covaxin 65.2%) was on par with their much hyped contemporaries in the US 4/

Now, the FDA has authorized a third dose of #Pfizer & #Moderna’s vaccines for immunocompromised. Is the decision, right? May be for the immunocompromised 5/

nytimes.com/2021/08/12/us/…

But for general population, we need to first sort out the one key issue: Was it the real waning of the #Pfizer vaccine or merely the low VE against the #Delta as its prevalence had increased during the later months in #Israel? 6/

So, what do we need? A booster/3rd dose of generic #SARSCoV2 dose or a specific booster against #Delta with revised formulation? 7/