Use good flea control. A clean environment is important. Keep your pet's living and feeding areas clean. Wash your pet's bedding regularly. Stay away from animals that have diarrhea.
Neuter pets to avoid roaming and discharges.
Keep the litter box away from the kitchen and eating areas. Change the litter box daily. It takes the toxoplasma parasite at least 24 hours to become infectious. If possible, have someone do it who's not at risk. Use disposable plastic liners and change them each time you change the litter.