In Jainism, ahimsa (non-violence) extends to all living beings, including tiny life forms like bacteria. The core principle is to avoid causing harm to any living soul as much as possible.

What that means in practice:

• Deliberate harm to bacteria without necessity is discouraged.
• In situations like illness, life-preserving actions (e.g., medical treatment prescribed by a physician) are generally considered appropriate, even if they result in the harm or death of some microbes. The emphasis is on protecting human life and reducing suffering.
• Striving for hygiene, careful food handling, and minimizing unnecessary injury to any living beings aligns with the spirit of ahimsa.

Key nuance:

• Jain ethics emphasize intention and necessity. If harming bacteria is avoidable or incidental, one should minimize it. When there is genuine need to treat illness and preserve life, those actions are generally viewed as permissible within the broader framework of ahimsa.

If you’d like, I can look for a specific Jain Dharma reference that discusses ahimsa and microbiology in more detail.