Do i have giardiasis if no symptoms but swam in kerala?

Usually not: Just because you swam somewhere doesn't mean you will get giardia. It is a parasite and is acquired by swallowing it (contaminated food or water). The symptoms ate gas, cramping pain, and on and off diarrhea.

Probably not: You generally shouldn't worry about GI parasites unless you're sick. Giardiasis isn't subtle, and you get it by drinking contaminated water or eating contaminated food, not by swimming.

Giardiasis: Occassionally there are no symptoms - but that is not the norm. Is this Kerala in India? Is the water you swam in known to be contaminated? Usual symptoms are diarrhea, oily floating stool, gas, nausea, vomiting & abdominal cramps. If untreated it can cause bloody diarrhea, dehydration & weight loss.