_  A study done on Toxoplasma gondii, a parasite commonly hosted in cats known for the potential complications it cause for human pregnancies, suppressed the immune system and is found to have some positive effects on Alzheimer's disease mouse models .This parasite promotes a significant decrease in the amount of b-amyloid plaque deposition, a hallmark of Alzheimer's disease, and not to forget the better performance in behavior tests like a water maze.