Can someone have listeria & not know it?no symptoms purely educational as there's a few stomach bugs goin in my household at the moment i'm pregnant

Listeria: Listeria is usually transmitted food to person ,not person to person except mother to fetus. It can be w/o symptoms. Use basic precautions not sharing food ,utensils washing hands. Eat only pasteurized cheeses, avoid deli- smoked non cooked raw meats / fish(sushi) , sprouts. You can get a blood test for listeria. The bug at home is likely viral f/u/w/ doc https://www.cdc.gov/listeria/faq.html