A teacher at Cleethorpes Academy, a member of staff at St Lawrence Academy in Scunthorpe, and a pupil at Stallingborough C of E Primary School all tested positive for COVID-19 since the start of term.
The teacher at Cleethorpes Academy has tested positive for coronavirus and is now self-isolating.
The secondary school, part of the Tollbar Multi Academy Trust, confirmed that the member of staff practiced social distancing at all times.
Principal Janice Hornby said there has been minimal risk to students and other staff due to the strict measures in place at the academy.
She said: “We want to reassure parents that the situation is under control and we have followed advice from Public Health England in responding to this matter.
“The member of staff did not come into close contact with any students or other members of staff and we have been advised by Public Health England that no further action is required at this time.”
St Lawrence Academy in Scunthorpe has also taken precautionary measures after a member of staff tested positive for coronavirus.
The individual booked a test after being in contact with an infected person outside the academy a few days earlier. They tested positive on Sunday.
They had not taught children, but had been in contact with several other colleagues last week, all of which stayed off work this week and have since tested negative for the virus.
Due to this, the academy is effectively without 20% of its teaching staff over the next two weeks.
Principal Mike Adnitt said: “I appreciate this will cause a great deal of inconvenience to Years 8 and 9 and their families at a time when everybody was just getting back to normality. We send our best wishes to the member of staff affected.”
Mr Adnitt added that Years 7, 10 and 11 should attend school as normal over the next two weeks. Year 9 this week and Year 8 next week can log on with lessons provided online.
Meanwhile, a whole class bubble has been told to self-isolate for 14 days after a pupil tested positive at Stallingborough C of E Primary School. The school is open as normal for the remaining pupils.