GUILDERLAND — For the third day in a row, Superintendent Marie Wiles has sent out a “Dear GCSD Families” email announcing another case of COVID-19 in the Guilderland Central School District.

On Friday evening, the newest case was at the district’s hardest-hit school, Guilderland High School. This is the district’s 30th case so far this school year.

“Today a member of the Guilderland High School community contacted the district to inform us of their positive COVID-19 test results,” Wiles wrote. “At this time, the Albany County Department of Health has not confirmed this case.

“In the interest of time, GHS principal Michael Piscitelli is following their guidelines to determine who needs to quarantine and is notifying those individuals. The department of health should be following up with them as well.

“Once the department of health confirms this case,” Wiles wrote, “it will be reported and will appear on the NYS COVID-19 Report Card for our district.”

Guilderland High School, according to the state’s dashboard, has had a total of 16 positive cases this year — 12 students and four staff members. Friday’s case would bring the tally at the high school to 17.

This school year, the high school has been on a hybrid schedule with some in-person and some remote classes. The high school had moved to all-remote learning from Nov. 19 until Thanksgiving break because of a staff shortage due to quarantine requirements. The original high school schedule resumed on Monday, Wiles told The Enterprise earlier this week, adding, “It’s back to normal.”

Wiles’s Friday evening email concluded, “It is important to remember to complete the daily health screening before sending your child to school. If your child has symptoms of COVID-19, please contact your health care provider and school nurse as soon as possible. You can find more information about protocols for returning to school here on the district website.”

Albany County has launched two testing sites — one of them in Voorheesville — where students with symptoms like coughing and running a fever, who are therefore excluded from classes, can get tested for COVID-19. Appointments are coordinated through school nurses.