People who are fully vaccinated are 91 percent less likely to become infected by COVID-19, according a new study by the Centers for Disease Control & Prevention.
The study, conducted in part by Baylor Scott & White Medical Center in Temple, increased evidence of the effectiveness of the Pfizer and Moderna vaccines.
The study reveals that vaccinations benefit people who get the disease despite being fully vaccinated or partially vaccinated.
“COVID-19 vaccines are a critical tool in overcoming this pandemic,” said Dr. Rochelle P. Walensky, CDC director.
Dr. Manjusha Gaglani, director of the Center for Research in Vaccines and Infections at Baylor Scott & White Medical Center in Temple, said this study adds to accumulating evidence that vaccines are effective and should prevent most COVID infections.
“Fully vaccinated people who still get the disease are likely to have milder, shorter illness and appear to be less likely to spread the virus to others,” Gaglani said.
Walensky said the study should alleviate fears of the vaccination.
The study examined data collected from health care workers, first responders, frontline workers and others deemed as essential personnel, she said. “These groups are more likely to be exposed to the virus that causes COVID because of their jobs.”
Nearly 4,000 participants were tested weekly from Dec. 13, 2020, to April 10, 2021, in eight U.S. locations, including Temple. Those that had positive nasal swabs were further tested to determine the amount of detectable virus in the nose and the number of days that they tested positive.
More than 350 of the study’s participants were tracked in Temple, Dr. Gaglani said. The local group consisted of health care and front-line workers from Bell and surrounding counties.
In order to evaluate vaccine benefits, study investigators accounted for the circulation of the virus in the area and how consistently participants used personal protective equipment such as masks and gloves at work and in the community.
Once fully vaccinated, Walensky said, participants’ risk of infection was cut by 91 percent. After partial vaccination, the risk was reduced by 81 percent.
“These estimates included symptomatic and asymptomatic infections,” she said.
To determine whether illnesses were milder, participants who became infected were combined into a single group and compared to participants where were infected but unvaccinated.
“Several findings indicated that those who became infected after being fully or partially vaccinated were more likely to have a milder and shorter illness compared to those who were unvaccinated,” Walensky said.
“For example, fully or partially vaccinated people who developed COVID-19 spent on average six fewer total days sick and two fewer days sick in bed,” she said. “They also had about a 60 percent lower risk of developing symptoms, like fever or chills, compared to those who were unvaccinated.”
“Other study findings suggest that fully or partially vaccinated people who got COVID-19 might be less likely to spread the virus to others,” she said. “For example, fully or partially vaccinated study participants had 40 percent less detectable virus in their nose, and the virus was detected for six fewer days compared to those who were unvaccinated when infected.”
Dr. Gaglani encourages those who have not received a COVID vaccine to do so.
“COVID vaccines are generally safe and highly effective in preventing infection with the SARS2 coronavirus,” Gaglani said.
“Getting vaccinated as soon as possible to reduces the risk of getting sick from COVID-19 and spreading the infection to family and friends.”