While all stool specimens should be handled with standard precautions, Balantidium coli trophozoites present a unique and heightened risk. They are large (up to 200 µm) and ciliated, making them highly motile. If a wet mount preparation of fresh diarrheic stool containing B. coli trophozoites is mishandled—for example, if a coverslip is pressed too hard or a slide is dropped—the fluid can aerosolize. The motile trophozoites in these droplets could potentially be inhaled. If inhaled, there is a documented, albeit rare, risk of pulmonary infection, as B. coli can cause extraintestinal disease. This is a classic example of a parasite requiring special biosafety considerations (enhanced hygiene, use of biosafety cabinets for manipulating liquid samples, and face protection) beyond universal precautions to prevent exposure via an unusual route (respiratory). Giardia and other flagellate cysts are not motile and are not transmitted via aerosols.

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Zambia

• Joseph Soko – 101 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies