The first case of swine flu in the Roanoke Valley was confirmed at Salem High School this week, according to Salem school officials.

The case was reported in a letter sent to parents Friday, the last day of classes.

School officials did not specify the severity of the case or whether the individual was a student or staff member, citing patient confidentiality.

"Based on information shared with me by the health department, the probability of transmission of the virus at the school was very low," Salem School Superintendent Alan Seibert said in a prepared statement late Saturday. "The understandably high level of confidentiality afforded to students by a school division and patients by health care professionals prevent me from sharing any further information."

The U.S. Centers for Disease Control and Prevention has said that the H1N1 influenza virus, or swine flu, does not appear to be more severe than seasonal flu and has recommended that good hygiene is the best defense against the communicable disease.

At least 84 cases of swine flu have been confirmed in the state with relatively few hospitalizations and one death, according to the Virginia Department of Health. In early May, at least nine of those cases were reported at Washington and Lee University in Lexington.

Salem school officials said in the letter that the state health department authorized them Friday to report the case to the public.

Kim Woolwine, whose 17-year-old son will be a senior at the school next year, said she learned of the case when she opened her mail Saturday afternoon. She said it appeared that school administrators made an effort to communicate with her and other parents as quickly as possible.

"It sounded from the letter that they just found out themselves," she said. "I was just a little surprised hearing that it hit this close to home."