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The Latest: Johnson & Johnson’s vaccine nears approval

Dear Reader,

Today, the Coronavirus Blog team is patiently awaiting the verdict from the Food and Drug Administration’s daylong advisory panel meeting on the Johnson & Johnson vaccine. If experts give it the green light, the FDA could approve the vaccine as early as Saturday.

The Johnson & Johnson vaccine could greatly help speed up the U.S. vaccine rollout because it only requires one shot and doesn’t need special refrigeration, as Emily Mullin notes in a fascinating explainer on its inner workings. The United States has secured 100 million doses of the vaccine, though they likely won’t be widely available until April because of manufacturing delays.

Keep an eye on the Blog for updates on the vaccine’s approval. While you’re on the site, you might notice a brand-new navigation bar at the top of the page. It’s there to help you access our latest coverage on various Covid-19-related topics quickly and easily.

I’ve really enjoyed hearing from Blog readers. Last week, a reader asked whether it was wise to plan a summer vacation; much as I wished I could say yes, travel is still not recommended right now. If you’ve got any questions about Covid-19, feel free to email me any time.

Stay safe and stay hopeful,

Yasmin Tayag
Editor, Medium Coronavirus Blog

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Recently updated mask guidance from the Centers for Disease Control and Prevention suggested wearing a disposable mask “knotted and tucked” to ensure a tighter fit on the face. It’s a great way to add security to your mask, but the CDC’s instructions for doing so can be puzzling. Here’s a step-by-step explanation:

1. Fold your mask in half lengthwise.

2. With the mask still folded, take one ear loop and knot it, keeping the knot as close as possible to the edge of the mask. Repeat on the other side.

3. Unfold your mask. It should look like a little canoe with holes on either end. Fold the extra fabric on each end inward, as if to close up the canoe.

4. Put on the mask, taking care to make sure the fabric you folded inward stays folded.

Read the full story for illustrated instructions.

Pfizer’s vaccine just got easier to distribute. One of the downsides of Pfizer’s otherwise great vaccine is that it requires storage in ultracold temperatures — at least, according to the original protocol. This has made distribution more complicated. But last week, Pfizer submitted data to the FDA showing that the vaccine could actually be stored under normal freezer conditions. On Thursday, the FDA released new guidance giving the thumbs up to this new storage option, paving the way for a smoother rollout. Read more.

Why Johnson & Johnson’s vaccine only needs one shot. Unlike the vaccines from Moderna and Pfizer, which use mRNA technology, Johnson & Johnson’s vaccine uses a viral vector, a more traditional approach. A viral vector is a modified virus — one that isn’t infectious — that can deliver genes from the target virus to our cells. Johnson & Johnson uses a virus called Adenovirus 26 as its viral vector. As one expert told Emily Mullin, adenovirus vaccines tend to induce a robust immune response, which is why they often only need one dose. Read more.

Fat stigma and the vaccine. The inclusion of high BMI as one of the criteria for vaccine eligibility in some states has its pros and cons, as Virginia Sole-Smith argues in a compelling piece in Elemental. On one hand, people with high BMI are at higher risk for severe Covid-19 and should be protected. But on the other, putting high BMI in the same eligibility category as pulmonary disease and cancer perpetuates fat stigma, which negatively impacts the quality of medical care that fat people receive. Read more.

What’s in Johnson & Johnson’s Covid-19 Vaccine?

Podcast: Filipino nurses have been disproportionately affected by the pandemic

What’s Driving Inequitable Covid-19 Vaccine Distribution?

A Golden Rule for a Semi-Vaccinated World

Editor, Medium Coronavirus Blog. Senior editor at Future Human by OneZero. Previously: science at Inverse, genetics at NYU.