Nearly a third of health care staff in U.S. hospitals were not vaccinated against COVID-19 as of mid-September, a new study shows.
Researchers analyzed data on more than 3.3 million health care workers at more than 2,000 hospitals nationwide between Jan. 20 and Sept. 15.
"Our analysis revealed that vaccine coverage among U.S. hospital-based [health care personnel] stalled significantly after initial uptake," said lead author Hannah Reses, an epidemiologist at the U.S. Centers for Disease Control and Prevention.
Between January and April, vaccination rates quickly rose from 36% to 60%, but then slowed substantially, reaching 70% as of Sept. 15, the study found.
While vaccination coverage increased just 5% between April and August, it rose another 5% from August to September. Researchers said the jump may have been a response to rising COVID rates associated with the highly contagious Delta variant or vaccination mandates in some areas.
By the study's end, the highest vaccination rates were seen in children's hospitals (77%), followed by short-term acute care hospitals (70.1%), long-term acute care hospitals (68.8%) and critical access hospitals (64%).
Rates were higher in hospitals in metropolitan counties (71%) than in rural counties (65.1%) and non-metropolitan rural counties (63.3%), according to findings. By U.S. government definitions, most counties, whether metro or non-metro, contain a combination of urban and rural populations.
The study was published Nov. 18 in the American Journal of Infection Control.
"Additional efforts are needed now to improve [health care personnel] vaccine coverage and reduce the risk of SARS-CoV-2 transmission to patients and other hospital staff," Reses said in a journal news release.
Ann Marie Pettis, president of the Association for Professionals in Infection Control and Epidemiology, noted that hospital-based health care workers play a "critical role in influencing community uptake of vaccines." They are also at increased risk for getting COVID and spreading it, she added.
"The findings from this analysis suggest that vaccine mandates as well as investment in additional educational and promotional activities could help increase vaccine coverage among [personnel] to better protect public health," Pettis said in the release.