Microorganism

A microorganism is any living organism too small to be seen with the naked eye, including bacteria, viruses, fungi, protozoa, and some algae. Some are harmless or beneficial, while others (pathogens) can cause infection or spoilage.

Hygiene and disinfection programmes are ultimately designed to control harmful microorganisms on hands, surfaces, equipment, food, and in water.

Referenced in disinfectant efficacy claims, environmental monitoring, food safety limits, and infection prevention policies.