Which of the following is NOT a symptom of Giardiasis?

Giardiasis is an intestinal infection caused by the parasite Giardia lamblia. It commonly presents with certain gastrointestinal symptoms. Among the options provided, vision problems are not associated with giardiasis.

The hallmark symptoms of giardiasis include prolonged diarrhea, which may be watery and sometimes accompanied by other digestive disturbances such as abdominal cramps and bloating. Severe weight loss can occur as a result of malabsorption associated with the prolonged diarrhea, leading to nutritional deficiencies. Fever may also be present in some cases, though it is not the most prominent symptom.

Vision problems, on the other hand, are not linked to giardiasis. This clarifies why the correct answer points to vision problems as the symptom that does not relate to this particular infection.