Thread by @opinion

Following pandemic news too closely can be an emotional roller coaster, with dire public health warnings immediately followed by hopeful new studies.

Here’s a hopeful new study: Vaccines sharply cut all Covid-19 infections — not just symptoms trib.al/O7A3VUE

The new data were collected from 4,000 people who were vaccinated with the Pfizer or Moderna vaccines between December 2020 and March 2021. The group was made up of:

👩🏽‍⚕️Health care workers
🚑First responders
🥡Delivery workers
👨🏼‍🏫Teachers
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The participants were asked not only to monitor symptoms but also to test themselves weekly.

The study authors concluded the vaccines caused a 90% reduction in all infections. If people aren’t getting infected, they can’t transmit the virus to others trib.al/O7A3VUE

New virus variants are also a worry, as some have shown ability to evade antibodies generated by the original strain.

But experts such as @DrPaulOffit are more optimistic. The vaccines show some efficacy against all the currently known variants trib.al/O7A3VUE

Offit saw enough evidence of decreased transmission that he said he liked the idea of issuing vaccine passports for travel.

Data from Israel, where most of the population is already vaccinated, show rapidly dropping deaths and hospitalizations trib.al/O7A3VUE

The new study should also allay fears that the vaccines’ astounding clinical trial results wouldn’t hold up in the real world.

One concern was a small sample size. While there were thousands enrolled in trials, infections were relatively uncommon trib.al/O7A3VUE

In this new study, there were 161 infections in the control group of 994 unvaccinated people.

By contrast, among the 2,479 participants who had two doses:

➡️8 infections between the 1st and 2nd doses
➡️3 infections after they were fully vaccinated trib.al/O7A3VUE

Vaccines induce not just antibodies, but so-called cellular immunity meaning they stimulate production of specialized virus-fighting cells called T-cells, which compared to antibodies:

✅Work against a broader range of variants
✅Last longer
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The Johnson & Johnson vaccine was only used in five people in the CDC study, but induces cellular immunity after just one shot.

The Pfizer and Moderna vaccines induce T-cells only after two shots trib.al/O7A3VUE

.@MonicaGandhi9 believes the shots will effectively end the pandemic because the T-cells can fight different variants.

“I do understand it almost seems too good to be true that the vaccines will get us out of this,” she says. “But they will” trib.al/O7A3VUE

It’s hard to predict the course of this pandemic, but vaccine experts do see the possibility the virus could become less of a threat.

Then it’ll be hard to hold back a return to normal life — one with restaurants, travel, and yes, roller coasters trib.al/O7A3VUE

For more on vaccines and the return to normal, listen to @fayeflam's podcast, "Follow the Science" on iTunes and Spotify: