Dvir Aran on Twitter
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You’ve probably seen reports from Israel on low vaccine effectiveness in this wave. Is it because of Delta? Waning immunity? We think the reason is mostly that we got the denominator wrong.https://t.co/yloh5Vo9Xi— Dvir Aran (@dvir_a) July 27, 2021

The Israeli study finding that Pfizer is only 39% effective against Delta calcualted that figure by dividing the covid surge in cities with high vaccination rates to the Israeli national average of people vaccinated. This is a bad comparison because you have to compare apples to apples, and the denominator of that study should have been the vaccination rate of people in cities.

Because vaccination rate is higher in Israeli cities than the national average, the study compared an accurate estimate of the number of cases to a gross undercount of the number of people vaccinated. As a result, the numerator was correct but the denominator was way too low, which resulted in an estimate of effectiveness that was way too low as well.

This wasn't hard to predict. Every other study around the world estimated the vaccine's effective against symptomatic COVID at ~80%, so any study that claims it's 39% should be seriously scrutinized. Now that that study has been scrutinized more, it clearly doesn't hold water and we should accept the null hypothesis of ~80%.

tl;dr: the vaccine keeps working, and the anti-vaxxers can stay wrong and stay mad.

  • layla
    ·
    3 years ago

    I hope so, but we all know people in the West will be on their third or fourth shot before people in the global south even get their first. And anyway, nobody (afaik) in the global south is getting mRNA vaccines, which are the more effective kind.

      • nohaybanda [he/him]
        ·
        3 years ago

        Meanwhile we're throwing doses out bacause a stupid amount of people here in Bulgaria are anti-vaxxers. :agony-minion:

        I'm so sorry comrade. We should send all our doses to countries which need and want it.

    • aaaaaaadjsf [he/him, comrade/them]
      ·
      3 years ago

      I live in the global south, and I unironically support US people getting an unofficial booster shot or third dose at this point, provided they consult with the appropriate medical professionals. The US isn't sending vaccines our way, and the antivaxx chuds aren't going to get the vaccine anytime soon. Might as well make use of these doses before they expire.

      • layla
        ·
        3 years ago

        Yeah I agree, the issue is that they're hoarding the vaccines in the first place.

        • aaaaaaadjsf [he/him, comrade/them]
          ·
          3 years ago

          Yeah that's the biggest issue. It sucks do bad, I can only start to register for a vaccine by the 1 September. If I get vaccinated before the end of the year it'll be a miracle