Which organism is commonly associated with waterborne outbreaks and grows on buffered charcoal yeast extract agar?

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Multiple Choice

Which organism is commonly associated with waterborne outbreaks and grows on buffered charcoal yeast extract agar?

Legionella is strongly linked to water systems and can cause outbreaks when people inhale aerosols from cooling towers, pipes, and hot tubs. In the lab, this organism is grown on buffered charcoal yeast extract agar because it needs a specialized environment to thrive. The charcoal in the medium helps detoxify and absorb substances that would inhibit growth, while the yeast extract provides a rich nutrient base. Importantly, the growth factors iron and cysteine are essential for Legionella, and these are added to BCYE to support its development. Most other common respiratory bacteria do not require this combination and do not grow as well on BCYE, which is why this medium is a classic tool for isolating Legionella from environmental or clinical samples. Mycoplasma pneumoniae relies on cholesterol-containing media and is transmitted more by person-to-person contact, not typical waterborne outbreaks. Staphylococcus aureus grows well on standard media like blood or mannitol salt agar and isn’t characteristically tied to water systems. Haemophilus influenzae requires X and V factors and grows best on chocolate or specialized media, not BCYE.

Legionella is strongly linked to water systems and can cause outbreaks when people inhale aerosols from cooling towers, pipes, and hot tubs. In the lab, this organism is grown on buffered charcoal yeast extract agar because it needs a specialized environment to thrive. The charcoal in the medium helps detoxify and absorb substances that would inhibit growth, while the yeast extract provides a rich nutrient base. Importantly, the growth factors iron and cysteine are essential for Legionella, and these are added to BCYE to support its development. Most other common respiratory bacteria do not require this combination and do not grow as well on BCYE, which is why this medium is a classic tool for isolating Legionella from environmental or clinical samples.

Mycoplasma pneumoniae relies on cholesterol-containing media and is transmitted more by person-to-person contact, not typical waterborne outbreaks. Staphylococcus aureus grows well on standard media like blood or mannitol salt agar and isn’t characteristically tied to water systems. Haemophilus influenzae requires X and V factors and grows best on chocolate or specialized media, not BCYE.

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