Well you would know for certain if they are isolated from a stool sample. Some people are carriers and they have no symptoms or mild symptoms. For others a Giardia infection means severe abdominal cramping and diarrhea. Symptoms can also include any (or none) of the following: loss of appetite, lethargy, upset stomach, bloating, flatulence. Giardiaisis is relatively uncommon in the US. It is contracted by the oral fecal route and can be caught from animals. People working in daycare, hikers, travelers and those who work with wild animals are most at risk. You can also catch this illness from contact with a person or animal with Giardiasis. You can prevent this illness by only drinking treated water, boiling water before drinking when camping and washing hands after contact with sick people or animals (or dirt). An infection is treated with one of several antibiotics if it is stubborn but usually the body is able to eliminate this infection on its own.

Yes, you can, though it helps if you're already healthy. In fact, according to Medicine for Mountaineering, most people develop a resistance to it after their first exposure; but because there are many other bacteria and viruses that produce similar reactions as Giardia, it often takes the blame for it.

"If the disease remains untreated, the body may adjust to the parasite, and virtually no symptoms will remain. Studies indicate that as many as 10% of Americans may carry the parasite at all times."

Raw vegetables

is the giardia a preditor or prey

well, it depends on what you mean by hidden virus...

the best answer i can give you is that it is not a hidden virus based on the fact that it is not a virus.. so yeah

Giardia is a flagellated protozoan. These types of organisms also cause diseases like bacteria. They are eukaryotes instead of prokaryotes like bacteria. This means that they are larger and have organelles. Bacteria are the opposite.