In all, eight employees were terminated because they were not vaccinated or granted an exemption. Most of these employees did not submit an exemption request.

Babcock attributes success of the program to the support of hospital leadership and consistent communication from BJC staff that emphasized patient safety. "Overall, the program went very smoothly," she says. "We were able to talk with the people who had concerns about the vaccine and allay their fears. A large number of employees were really glad that we had made it mandatory and that co-workers were being vaccinated."

At the two teaching hospitals that are part of BJC HealthCare, Barnes-Jewish Hospital and St. Louis Children's Hospital, all 907 medical residents and fellows complied with the mandatory policy; five received medical or religious exemptions.

Although physicians employed by BJC were required to get the flu shot, most physicians affiliated with BJC HealthCare are in private practice or are employed by Washington University School of Medicine and are not covered by the mandatory policy.

In the United States, influenza is associated with 36,000 deaths and more than 200,000 hospitalizations each year, and it is the leading cause of vaccine-preventable death. Other vaccines, including those for the measles, mumps, rubella and chicken pox, already are required by many health-care organizations, including BJC.

Babcock says she now plans to collect data for the 2009 flu season, when employees have been required to get both the seasonal flu vaccine and the H1N1 vaccine.