Cryptosporidiosis is a parasite that causes severe bouts of diarrhea and dehydration.
Eleven cases have been reported this month. That's three more than last year's total.
The bug passes by human waste coming into contact with water.
Hot spots for the bug are public pools and daycare centers.
Lubbock Health officials say there are some easy ways to avoid crypto.
"If people have diarrhea, don't go swimming for two weeks after the symptoms subside and wash your hands regularly," said Judy Davis of the Lubbock Health Department.
Children in diapers and people with weakened immune systems should also avoid public pools.
Most people get over the illness on their own, but some medical care may be required.