Isospora is a genus of protozoan parasites that can cause Intestinal Infections in humans, known as isosporiasis. The most common species associated with human infections are Isospora belli. These parasites primarily infect the small intestine and are transmitted through the ingestion of contaminated food or water, particularly in regions with poor sanitation. Clinical presentation of Isospora infections varies but often includes symptoms such as watery diarrhea, abdominal cramps, nausea, vomiting, and weight loss. Immunocompromised individuals, such as those with HIV/AIDS, are more susceptible to severe and prolonged infections. Isospora can cause chronic diarrhea in these populations, leading to malabsorption and nutritional deficiencies. Diagnosis of Isospora infections involves the detection of oocysts (the infective stage of the parasite) in stool samples. Stool microscopy, using acid-fast staining, is commonly employed for identification. Molecular techniques, such as polymerase chain reaction (PCR), can provide a more sensitive and specific diagnosis, particularly in immunocompromised individuals with low oocyst shedding. Treatment typically involves antimicrobial therapy with drugs like trimethoprim-sulfamethoxazole (TMP-SMX). Rehydration and electrolyte replacement may be necessary in cases of severe diarrhea. Preventive measures include practicing good personal hygiene, ensuring safe food and water sources, and avoiding consumption of undercooked or contaminated food.