noun
opportunistic pathogen
Medical term for a microorganism that normally does not cause disease but can become pathogenic when the host's immune system is weakened or the normal microbial balance is disrupted.
日和見菌は、免疫力が低下した患者に感染症を引き起こすことがある。
Opportunistic pathogens can cause infections in patients with weakened immune systems.
病原菌 is a general term for pathogenic bacteria, while 日和見菌 specifically refers to those that cause disease only under certain conditions.
Compound of 日和見 (ひよりみ, 'wait-and-see attitude, opportunism') and 菌 (きん, 'bacterium, fungus, microbe'). The term reflects the microorganism's opportunistic behavior.