The dean of the School of Public Health and Health Services resigned abruptly late last month to become a full-time faculty member at the school.

Ruth Katz, who served as the dean of SPHHS for five years, was replaced temporarily by Associate Dean Joseph Reum. Katz e-mailed members of the school in September to say that she was stepping down, but she did not cite reasons behind the decision.

“As many of you have heard, I will be leaving my position as dean of this school, and returning to the faculty as a full-time member of the Department of Health Policy,” Katz wrote in the e-mail. She did not respond to several requests for comment.

Donald Lehman, executive vice president for academic affairs, said deans generally only keep their posts for a handful of years.

“(Ruth Katz) has served for five years as dean of the school and it is not atypical for a dean at the five-year mark to step down,” he said. “We normally expect our deans to serve for at least five years.”

But the change in leadership comes amid concern from the Faculty Senate that the school has traditionally failed to meet the required number of tenured professors. The University quires that 75 percent of all full-time faculty members should be tenured or tenure-acquiring professors.

Lehman said the Faculty Senate was “concerned” about the number of tenured professors, but he said he had “no idea” if this was the reason for Katz’s decision to step down.

Reum said he filed a report with the Faculty Senate last week that outlines how the school plans to increase the number of tenured professors.

Officials from SPHHS contacted Lehman about developing a search committee for Katz’s successor, he said. Currently, no one has been appointed to the committee.

Reum said he has heard from several candidates who have “national standing and are interested in the position.” He would not comment if he had plans to apply for the post.

“What I want to do is the best job that I possibly can as the interim,” Reum said. “It is always best to do what is right in front of you and ahead of you.”

SPHHS, which has fewer than 1,000 students, is in the process of acquiring its own building. The Board of Trustees approved the hiring of an architectural firm that will begin designing plans for the building, Katz said last month.

SPHHS students currently take classes in the School of Medicine and Health Sciences building.

-Eric Thibault contributed to this report.