Final answer:
Outdoor interactive fountains can be a source of Giardia infection due to contamination with Giardia lamblia. The parasite's cysts resist chlorination and survive in cold water, and children are especially vulnerable to infection due to fecal-oral transmission pathways.
Step-by-step explanation:
Outdoor interactive fountains are commonly linked to Giardia infection because these environments can become contaminated with the parasite Giardia lamblia, which spreads through a fecal-oral route. Contaminated water or food, or direct contact with an infected individual, can transmit pathogens including this protozoan. The parasite's cyst stage is resistant to chlorination and can survive in cold water, making it difficult to eradicate from municipal water systems without proper filtration.
Children are particularly at risk for Giardia infection because of their propensity to put objects in their mouths and poor hand hygiene, which can lead to the ingestion of contaminated water from fountains. Outbreaks can also occur when public water supplies are contaminated, and symptoms of giardiasis include diarrhea, abdominal pain, and fever. Preventive measures include avoiding ingestion of untreated water from outdoor sources and ensuring good sanitation standards.