Pupils and staff at Hottsbridge, Canonbie and Closeburn primary schools are remaining at home due to cases in the school community.
There are also a small number of children from Lockerbie Academy isolating.
Hottsbridge closed on Friday, while Canonbie and Closeburn schools were closed on Monday.
They are all expected to reopen on Monday, May 10.
Additional testing capacity has been put in place in Lockerbie to deal with the small increase in cases.