Three school districts in the country have cancelled in-person learning this week as local officials report drastic drops in student and teacher attendance attributed to COVID-19 and other illnesses.

Two school districts in Kentucky announced in-person closures for this week, citing a rise in illness among staff and students. Magoffin County Schools said all schools will close Thursday and Friday due to widespread illness. School officials said attendance has been quite low in the past week, and a mixture of viruses, including COVID-19 and influenza, motivated the closure.

Lee County School District announced illness-related closures for Tuesday and Wednesday, and NTI days, or non-traditional instruction, for Thursday and Friday. Officials said there had been an increase in respiratory illnesses the last few days, and a significant drop in attendance motivated the closure.

Scott Lockard, public health director for the Kentucky River District Health Department, which serves Lee County and six others in eastern Kentucky, said that ever since the pandemic started, there has generally been a rise in illnesses when schools first go back into session as people return to large gatherings.

“There was a lot of illness in the county, and the absentee rate got up to the level where the school system felt it justified closing,” Lockard told USA TODAY.

So far, lab test data reported to the department in eastern Kentucky has confirmed positive COVID-19 results but no influenza cases. However, Lockard noted respiratory illnesses in general are a concern, as symptoms often overlap with COVID-19. Also, testing is not as readily available as it once was, and many people have turned to home tests, which means lab reports typically underscore the level of illness.

Runge Independent School District in southern Texas, which serves 195 students, announced a weeklong closure due to illnesses, ABC News reported. According to the district’s online COVID-19 tracker, ten of the district’s 43 staff members had tested positive for COVID-19 as of Monday.