SPOTSYLVANIA, Va. (AP) — Virginia health officials are expanding an advisory against swimming at Lake Anna after algae blooms spread to other parts of the lake.

News outlets report the Virginia Department of Health collected samples from the lake earlier this month and updated the harmful algae bloom map.

Seven areas now have no-swim advisories. The harmful algae blooms were detected in the upper areas of the North Anna and Pamunkey branches earlier this summer and they’ve now spread to the middle and lower areas of the branches.

The harmful algae can cause skin rashes and stomach illnesses. Officials say samples collected downstream at the Lake Anna State Park beach and the state Route 208 bridge were within safe limits.