COVID-19 vaccines as effective in real-world settings as in clinical trials

mRNA COVID-19 vaccines offer substantial protection from infection by the novel coronavirus, SARS-CoV-2, in the “real-world”, concludes a large study carried out at six regions across the U.S. including Salt Lake City, Utah. The performance of the vaccines was consistent with their performance in closely controlled clinical trials that led to their approval for emergency use.

The results are particularly noteworthy considering that participants in the study were amongst those at highest-risk for being exposed to the virus, the researchers say. These included health care workers, first responders and essential workers who routinely come in close contact with the public as a routine part of their job.

“There are usually differences in how well interventions perform in clinical trials as compared to real-world settings,” explains Sarang Yoon, assistant professor at the University of Utah Rocky Mountain Center for Occupational and Environmental Health (RMCOEH) and principal investigator of the RECOVER (Research on the Epidemiology of SARS-CoV-2 in Essential Response Personnel) study in Utah. In this case, the results support a large body of evidence, from clinical trials and other research, showing that COVID-19 vaccines are very safe and effective.

“This research is showing how well these vaccines work,” says Yoon.

Headshot of Sarang Yang.

Sarang Yoon, assistant professor at the University of Utah Rocky Mountain Center for Occupational and Environmental Health and principal investigator of the RECOVER (Research on the Epidemiology of SARS-CoV-2 in Essential Response Personnel) study in Utah.

The study published on March 29 in the Morbidity Mortality Weekly Report (MMWR) from the Centers for Disease Control and Prevention. Kurt Hegmann, director of RMCOEH, Matthew Thiese, associate professor and Andrew Phillips, assistant professor of RMCOEH were co-investigators on the Utah study. Additional study sites that are part of the HEROES-RECOVER network are Phoenix and Tucson, Arizona; Portland, Oregon; Duluth, Minnesota; and Temple, Texas.

The study showed the mRNA COVID-19 vaccines were:

  • 90% effective at reducing risk for infection once participants were “fully” vaccinated, two weeks after the second dose.
  • 80% effective at reducing risk for infection after “partial” vaccination, two weeks after the first dose (before the second dose was given).

Among those fully vaccinated, there were only 3 infections among 2,479 workers and no severe COVID-19 infections or deaths in people who were vaccinated. This is much lower when compared to the period when participants were not immunized, 161 infections were identified.

The authors note that even though the vaccines were highly effective after one dose, it is not known how long that immunity lasts. The CDC recommends two doses of the Pfizer-BioNTech and Moderna vaccines.

3,950 study participants submitted samples for COVID-19 tests on a weekly basis for 13 weeks between December 14, 2020 to March 13, 2021. During that time, 2,479 participants have been fully vaccinated, receiving two doses of either the Pfizer-BioNTech or Moderna mRNA COVID-19 vaccine. In addition to submitting samples for COVID-19 test, participants reported weekly whether they had COVID-like symptoms including fever, shortness of breath and loss of taste or smell.

Study participants were:

  • Health care workers (e.g. physicians, nurses, medical assistants),
  • First responders (e.g. firefighters, police officers, staff at correctional facilities), and
  • Frontline and essential workers (e.g. teachers, hospitality, retail, restaurants, airlines).

Results from COVID-19 tests and surveys also showed that among those who tested positive for SARS-CoV-2, 87.3% had COVID-19 symptoms and 10.7% were asymptomatic.

“We are incredibly grateful to our participants for their time and dedication to the study.” says Yoon. “With their help, we will be able to better understand COVID-19 vaccine efficacy and COVID-19 illness.”

The RECOVER study is ongoing and results from future phases will help determine how long COVID-19 vaccines protect against infection and the real-world effectiveness of newer vaccines.

The research will also investigate how well COVID-19 vaccines protect against new variants of the SARS-CoV-2 virus that are highly transmissible and are now circulating in the U.S.

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The research publishes as, “Interim Estimates of Vaccine Effectiveness of BNT162b2 and mRNA-1273 COVID-19 Vaccines in Preventing SARS-CoV-2 Infection among Healthcare Personnel, First Responders, and Other Essential and Frontline Workers – Six U.S. Region, December 2020-March 2021.”

Health and academic professionals with dependents at greatest risk of quitting after COVID-19

Up to one in five employees at an academic medical institution are considering leaving their professions due to the strains of coping with the pandemic in their own lives, according to a new University of Utah Health study. Individuals who had caregiving responsibilities were among those most likely to contemplate leaving or reducing hours.

The findings suggest that retaining highly trained doctors, nurses, and scientists in the aftermath of the COVID-19 pandemic could be the next great health care challenge.

Headshot of Angela Fagerlin.

Angela Fagerlin, professor and chair of the Department of Population Health Sciences at the University of Utah School of Medicine. Photo credit: Charlie Ehlert.

“It’s sobering to learn that, during a time of economic recession, at least one-fifth of our workforce were considering leaving their jobs because of the severe levels of stress they were experiencing,” says Angela Fagerlin, the study’s senior author and professor and chair of the Department of Population Health Sciences at the University of Utah School of Medicine. “Many of these are people who have spent five to ten years of their adult lives training to do this kind of work. Yet, it’s so overwhelming and burdensome that they were potentially thinking about giving it all up.”

Although conducted at a single health care system, the researchers say these findings could have broader implications.

“We suspect these disturbing trends likely exist within other health care systems nationwide,” says Rebecca Delaney, the study’s lead author and a postdoctoral research fellow at the U of U School of Medicine. “These findings are alarming and a warning sign about the morale and well-being of doctors and nurses, as well as non-clinical health care scientists and staff.”

The study appears in JAMA Network Open.

Several studies have examined the effects of burnout, stress, depression, and anxiety on frontline medical staff during the global pandemic. However, most have only included frontline workers or physician trainees. Few of these studies have addressed important family-work balance issues, such as childcare needs during the pandemic, which contribute significantly to the stress and burnout of staff.

To remedy this oversight, Delaney and her colleagues distributed a web-based survey of all 27,700 clinical and non-clinical U of U Health faculty, staff, and trainees in August 2020. Survey items measured childcare needs, work-life balance needs, career development impact, and stress related to the pandemic.

Overall, 18 percent (n=5,030) completed the entire survey. The data was consistent across clinical and non-clinical respondents, confirming that everyone—men, women, those with and without children—were struggling with the impact of COVID-19, Delaney says.

Nearly half (48 percent) reported having at least one child 18 years old or younger. In addition, the researchers found:

  • 49 percent of those who had children reported that parenting and managing virtual education for children was causing them stress
  • Faculty (55 percent) and trainees (60 percent) reported decreased productivity
  • 47 percent of participants expressed concern about COVID-19 affecting their career development, with 64 percent of trainees being highly concerned
  • 30 percent reported considering reducing hours
  • 21 percent reported considering leaving the workforce

In addition to being a single health care system survey, other study limitations included the possibility of selection bias among those who chose to complete the survey. It’s also possible that more employees with children aged 18 or younger responded than those without children.

Although the researchers found that burnout, depression, and anxiety were important, they concluded that greater emphasis on work-life balance, accessibility to dependent care, and ongoing psychological and social support could prevent thousands of medical caregivers from joining this potentially devastating exodus.

“Health care systems must develop effective ways to ensure that well-trained clinicians, support staff, and non-clinical scientists are supported during this unprecedented time as well as after it,” Fagerlin says. “If they do that, then health systems will be more likely to retain a diverse and effective workforce.”


In addition to Drs. Delaney and Fagerlin, U of U Health scientists Amy Locke, Mandy L. Pershing, Claudia Geist, Erin Clouse, Michelle Precourt Debbink, Benjamin Haaland, Amy J. Tanner, and Yoshimi Anzai contributed to this study.

The study, “Experiences of a Health System’s Faculty, Staff and Trainees Career Development, Work Culture, and Child Care Needs During the COVID-19 Pandemic” appears in JAMA Network Open. It was supported by a Jon M. Huntsman Presidential Endowed Chair awarded to Fagerlin, who is also a research scientist at the VA Salt Lake City Health Care System.

U OF U Health research plays major role in new CDC guidelines

Research from University of Utah’s Health and Economic Recovery Outreach (HERO) Project contributed to the Centers for Disease Control and Prevention’s (CDC) revised physical distancing guidelines that reduces the space between students in classrooms from six feet to three feet.

Utah HERO partnered with Granite School District within Salt Lake County to investigate how COVID-19 spreads in elementary schools. The study found low levels of COVID-19 transmission when students and staff wore masks and followed other prevention measures, even when students were unable to be spaced six feet apart and when community infection rates were high.

The study took place in 20 elementary schools in the Granite School District and one independent school in Salt Lake City. To determine whether a positive case was acquired in school or out of school, researchers gathered detailed histories about the positive patient, and tested their initial contacts and household members. Overall, researchers found five secondary cases that were likely due to school exposure for a rate of 7 per 1,000 contacts.

“In four or five of these cases, there were obvious breakdowns in prevention strategies, including poor mask use,” says Adam Hersh, lead study investigator and professor in the Division of Pediatric Infectious Diseases at U of U Health. “This helped us understand why transmission happened in these instances.” Researchers also found in most positive cases, transmission was more likely among members of their households than between two masked students.

Although the study looked at the risk of infection from COVID-19 in one school district, researchers say the information can be related to classrooms in any part of the country if masking and other prevention measures are in place. “In-person schooling can be done safely with multi-layer, strictly enforced prevention measures,” says Andy Pavia, chief of the Division of Pediatric Infectious Diseases at U of U Health. “It enforces and reinforces the Governor’s recommendation that we should continue masking throughout all schools in Utah and provides reassurance that we know how to keep schools safe.”

The study did not look at COVID-19 transmission out of the classroom. “When masks are on, three feet of distance between students seems to be safe,” says Hersh. “However, in circumstances where masks are off, such as lunch, it’s really important to ensure there is more spacing than three feet.” At the time of the study, extracurricular school activities were limited. Researchers say COVID-19 transmission may look very different when students are playing sports and doing other activities where the environment is not as controlled.

The study validates that COVID-19 prevention measures are working and that in-person learning can be done safely under these conditions. “We hope this provides reassurance for our school communities throughout the state and for other communities throughout the county, many of which are struggling with decisions around school opening and school operations,” says Hersh.

Statement from the CDC Morbidity and Mortality Weekly Report (MMWR):

The study from Utah published in the MMWR presented findings supportive of CDC’s revised guidance allowing for three feet of distance between children in school settings. The Utah study, one of many across the nation, affirmed CDC’s recommendation that schools should return to in-person learning and that doing so can be accomplished safely for the protection of students, teachers and communities.  

“Based on available science, like the joint publication today by CDC and University of Utah, schools remain a safe place for America’s students and teachers when following CDC’s guidance,” said Victoria Chu, MD, MPH and author of MMWR article published today. “CDC remains committed to ensuring America’s children can return to in-person schooling for their well-being and development.”