Two men from Rochester, New York, have succumbed to pneumonia after using bat faeces, commonly known as guano, as a fertilizer for growing cannabis. The incident has raised alarms about the potential health risks associated with this unconventional agricultural practice.

The deceased, aged 64 and 59, reportedly inhaled spores of the Histoplasma capsulatum fungus, which is prevalent in bat droppings. This fungus can cause histoplasmosis, a severe lung infection that can lead to pneumonia and in extreme cases, death. According to medical experts, the symptoms of histoplasmosis include fever, cough, fatigue and chest pain, which can escalate to more severe respiratory issues.

Dr. John Smith, a specialist from the University of Rochester, emphasized the dangers of using untested natural fertilizers. "While guano is often touted as a 'natural superfood' for plants due to its high nitrogen content, it can harbour dangerous pathogens," he stated. "It's crucial for individuals to ensure that any organic material used in agriculture is free from harmful fungi or bacteria."

The Centers for Disease Control and Prevention (CDC) has noted that while histoplasmosis is not typically fatal in healthy individuals, those with compromised immune systems or pre-existing conditions are at higher risk. The CDC estimates that around 250,000 Americans contract the disease annually, with a mortality rate of approximately 5 to 7 percent.

This incident highlights the growing trend of using bat guano in cannabis cultivation, particularly in regions where marijuana legalization is expanding. Health officials are urging caution and recommending that growers seek alternative fertilizers that have been independently tested for safety.