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COVID-19 vaccines ramp up, AstraZeneca safety confirmed

Health and Benefits|Wellbeing
COVID 19 Coronavirus

By Jeff Levin-Scherz, MD | March 22, 2021

The U.S. is vaccinating an average of 2.5 million people daily, but we seem “stuck” at an average of 50,000 new cases a day.

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About our “The COVID-19 Crisis” series

“The COVID-19 Crisis” series is weekly update by Dr. Jeff Levin-Scherz covering the latest developments related to the COVID-19 pandemic in the U.S. Explore the entire blog series.

Last week there was much good news in the fight against the COVID-19 pandemic, but there were also some worrisome signs.

First, the good news. The U.S. vaccination effort is ramping up rapidly; we are up to an average of 2.5 million doses of vaccine a day, and about 41 million Americans are now fully vaccinated. Supplies are increasing, and many states have announced plans to allow vaccination of all adults sometime over the next month.

The vaccines available in the U.S. still continue to be highly effective against the variants, including B.1.1.7 (U.K.) and B.1.351 (South Africa) and P.1 (Brazil). Data from Israel show dramatic declines in cases and transmission as that country has now vaccinated half of its population.

Caution signs

The U.S. continues to be at about 50,000 new cases a day, just a bit shy of the late July peak. The B.1.1.7 variant now represents about 40% of cases in the U.S., which could be part of the reason the rate of new infections isn’t dropping. Scientists estimate that this variant will be the dominant strain of the virus by the end of this month.

Current daily trends in number of COVID-19 cases in the U.S reflect a moving seven-day average number at 53,463. This is much lower than record highs in January, but on par with cases reported in July of 2020.
Daily trends in number of COVID-19 cases in the U.S. reported to the CDC

Yellow line signifies seven-day moving average number from January 22, 2020, to March 18, 2021.
Source: Centers for Disease Control and Prevention

AstraZeneca vaccine safety

Many countries briefly stopped administering the AstraZeneca vaccine last week due to concerns about blood clots. This is bad news, because the AstraZeneca vaccine is the lowest-cost vaccine with the largest amount of global manufacture.

One of the challenges of giving a vaccine to billions of people is that the vaccine will inevitably coincide with other medical events in a few people. This is especially true with vaccines that are prioritized for the elderly and those with chronic illnesses. Norway also investigated deaths of 21 frail elderly patients after receiving a vaccine in January and ultimately found the death rate in those getting vaccinated was no higher than expected.

Blood clots are common. Blood clots in the lung happen in 60 to 70 people per 100,000 annually, and blood clots in the leg are about twice as common. So in vaccinating a million people over a year, we’d expect about 2,000 clots — or about 40 per week.

Other bad medical events are common, too. In the U.S., there are 100,000 adults with new seizures each year, 800,000 heart attacks a year and 750,000 strokes a year. So some people who get vaccinated will have a bad medical event close to their vaccinations.

The AstraZeneca vaccine has not been granted emergency use authorization by the Food and Drug Administration, so this issue is not relevant in the U.S. However, the flurry of press coverage could set back efforts to get people vaccinated globally, not just in countries that have paused AstraZeneca vaccination.

The European Medicines Agency reviewed the AstraZeneca safety data, and announced its finding on Thursday that the AstraZeneca vaccine “is not associated with an increase in the overall risk of blood clots (thromboembolic events) in those who receive it.” The agency pointed out that there had been 25 cases of two rare types of blood clots among 20 million Europeans who were vaccinated and that it will keep researching the safety of the vaccine. The agency’s conclusion:

  • Because COVID-19 can be so serious and is so widespread, the benefits of the vaccine in preventing it outweigh the risks of side effects.

Though it has not been approved, the safety profile of the AstraZeneca vaccine still looks excellent. We may well see an emergency use authorization in the U.S. over the next month. Major European countries announced they would resume AstraZeneca vaccinations today, although I’m worried that the complicated message around bleeding events could scare some away from this vaccine. British Prime Minister Boris Johnson and French President Emmanuel Macron are both scheduled to get this vaccine today.

New CDC guidance on worksite vaccination

The CDC offered new guidance to employers considering workplace vaccinations, which are similar to what we’ve been advising. They recommend, as we’ve suggested, that employers considering vaccinating employees develop a relationship with the health department(s) in their jurisdiction(s) to be considered for vaccine as supplies allow and to engage a vaccination vendor.

Employers should note that the CDC continues to advise those who are vaccinated to wear masks and to participate in worksite screening or testing programs. I suspect the recommendations on testing those who are fully vaccinated will be eased soon, but the recommendations about masking will continue. If many who are vaccinated stop wearing masks, it’s more difficult to maintain a social norm of mask-wearing.

Other COVID-19 news

  • Studies of long-haul COVID-19 (Post-acute SARS CoV2) continue to show a disturbing frequency of residual effects weeks and months after recovery from the virus. Symptoms include fatigue, shortness of breath, chest pain, cough, loss of smell, joint pain, gastrointestinal complaints, impaired memory, poor concentration and anxiety and depression.

We have already heard that some with long COVID-19 have difficulty qualifying for disability benefits. People who have symptoms that are hard to categorize from a disease that is not yet well defined often feel like their complaints are being ignored. We should be careful to treat them with empathy. We don’t know how long these symptoms will last. On the bright side, some with long COVID-19 report that their symptoms subside when they are vaccinated.

  • A large Danish study shows that those who have had COVID-19 were about 80% less likely to get a new infection than those who had never had the virus. Protection was less complete for older people and declined a bit over time. Those who have had COVID-19 infections should still be vaccinated because the vaccines produce higher antibody levels, and we believe more and longer protection than a previous infection.
  • The EU and China have announced that they will be using some version of a vaccine passport to allow international air travel. Many companies are offering U.S. companies apps that show vaccine status, although most are dependent upon attestation. Some require uploading the CDC handwritten vaccine card; the most valuable proof of vaccination would include electronic verification.

Despite setbacks in vaccination outside the U.S. and the increase in the prevalence of COVID-19 variants, the increase in the number of vaccines available and those eligible to be vaccinated warrants optimism.


Population Health Leader, Health and Benefits, North America

Jeff is a practicing physician and has led Willis Towers Watson’s clinical response to COVID-19. He has served in leadership roles in provider organizations and a health plan, and is an Assistant Professor at Harvard Chan School of Public Health.

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