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Katelyn Jetelina updated her COVID-19 vaccine comparisons table on 5/20/21 at her site Your Local Epidemiologist. Highlights include the latest data on how well various vaccines protect against SARS-CoV-2 variants. The post also includes a helpful discussion of two ways that researchers measure how well a vaccine works – efficacy (analyzing the extent of disease protection in experiments) and immunogenicity (analyzing levels of a type of antibodies made in response to a pathogen over time).

A total of 23 U.S. states and Washington, D.C., recently have changed their face-coverings and mask guidance in response to last week's Centers for Disease Control’s update to its guidance for fully vaccinated people, reports Lindsay Kalter for WebMD (5/18/21). The WebMD story’s second page links to various state plans for lifting mask mandates.

A growing body of evidence, including a study published 5/15/21 in The Lancet and another published 5/6/21 in JAMA, suggests that the Pfizer-BioNTech vaccine not only protects us against moderate or severe COVID-19. It also protects us against getting infected at all with SARS-CoV-2 and thereby protects against us transmitting infections to others. Lower amounts of the virus persist in the nasal passages of vaccinated people than in those of unvaccinated people, Dr. Anthony Fauci said 5/16/21 on CBS News’ “Face the Nation.” There are very rare “breakthrough infections” of SARS-CoV-2 in vaccinated people, but “almost always the people [with these infections] are asymptomatic [feel no symptoms], and the level of virus is so low, it makes it extremely unlikely, not impossible, but very, very low likelihood that they are going to transmit it,” Fauci said. These findings, along with ongoing evidence that the vaccines are safe and effective, even against SARS-CoV-2 variants, provided the scientific basis for the U.S. Centers for Disease Control’s guidance (5/13/21) stating that vaccinated people no longer need to wear masks nor socially distance in most indoor and outdoor settings, even crowded ones, reports Apoorva Mandavilli at The New York Times (5/14/21).

In a New York Times survey conducted between April 28 and May 10, 85% of more than 700 epidemiologists responded that they think people in the U.S. will be able to safely gather outdoors on the Fourth of July, as the nation “rounds the bend” (as some writers put it) on the COVID-19 pandemic. Nearly the same percentage of epidemiologists think that U.S. schools can safely reopen in the fall, according to the survey results, as reported by the Times. Another notable finding from the survey: the majority (59%) of the surveyed epidemiologists think that vaccination rates are the most important statistic to examine when considering whether to "resume most pre-pandemic activities without new COVID-era precautions.” So, what vaccination rate or level should you look for? "Half of respondents said at least 80 percent of Americans, including children, would need to be vaccinated before it would be safe to do most activities without precautions," write Claire Cain Miller, Kevin Quealy, and Margo Sanger-Katz (5/15/21).

And where does one find U.S. federal, state, and county vaccination rates? Some experts frequently consult The New York Times' various COVID-19 dashboards, including this U.S. vaccinations tracker, which allows you to look up the percentage of people in each U.S. county who are fully vaccinated. Of course, any single statistical measure provides limited information. Additional factors that influence a region’s SARS-CoV-2 risk include local immunity among people who have recovered from SARS-CoV-2 infections or COVID-19 in the past 14 months (areas that have recovered from coronavirus surges will have higher rates of this “natural immunity”) as well as public-health measures such as masking and distancing requirements.

In freelance journalist Tara Haelle’s 5/13/21 story for Scientific American about the recent U.S. authorization for use of the Pfizer-BioNTech vaccine in adolescents, I learned about a site called VaxTeen. The site states that it is designed to address “the decline in vaccinations” in the U.S. by directly informing teenagers and young adults about vaccine misinformation and encouraging these groups to catch up on any missing shots. One of the site’s main resources is a state-by-state index where teens may look up their legal rights to obtain a vaccination without parental consent. Each state entry includes a statement on how the local laws pertain to COVID-19 vaccinations.

Accumulating research reveals that COVID-19 vaccines are safe and effective during pregnancy, even against some of the SARS-CoV-2 variants (e.g. B.1.1.7, first identified in the UK, and B.1.351, first identified in South Africa), reports Emily Anthes for The New York Times (5/13/21). “Vaccinated women can also pass protective antibodies to their fetuses through the bloodstream and to their infants through breast milk,” Anthes writes, describing the results of a study published 5/13/21 in JAMA. And neither the Pfizer-BioNTech vaccine nor the Moderna vaccine harms the placenta during pregnancy, Anthes describes a 5/11/21 study as concluding. More research is needed to study these same questions in women at earlier stages of pregnancy, the story states.

You might enjoy, “An open letter to sleep: we need to talk,” by Viktoria Shulevich for McSweeney’s (5/20/21).

This is an opinion and analysis article.