The Bewdley School, off Stourport Road, confirmed it was liaising with Public Health England after the confirmed case.
In a letter to parents, published on The Bewdley School's website, the headteacher said the member of staff's symptoms began on Saturday – and the staff member had been teaching "only five separate classes" on Thursday and Friday.
The letter said that they were confident that "social distancing was maintained between the staff member and all students on both days." It adds that the school will remain open and no students will be contacted to self isolate.
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The letter states: "I am writing to inform you that we have been notified that a member of staff has tested positive for Covid-19. Data protection requirements obviously make the identity of the member of staff confidential.
"We have been liaising with Public Health England and the local Health Protection Team and I can confirm that the individual started experiencing symptoms on Saturday afternoon and has not been in since as per our risk assessment.
"To determine whether the staff member has been in contact with others who now might be at risk of infection, Public Health England are using the following time frames: if symptomatic: two days before onset of symptoms until 10 days after onset of symptoms; and if asymptomatic: two days before date of test until 10 days after date of test.
"As the symptoms started on Saturday, we have looked in detail at the two days before – the member of staff was in school on Thursday and Friday teaching only five separate classes.
"Following detailed discussion with the member of staff and the Health Protection Team, we are confident that social distancing was maintained between the staff member and all students on both days. Therefore, the school will remain open as usual and no students will be contacted to self-isolate."
It comes only days after the school confirmed another Covid-19 case within the school, in a letter published on their website on October 1. It is not known whether the first confirmed case was a pupil or teacher, and when approached by the Express & Star the school declined to comment further.