noun
infectiousness; contagiousness
Refers to the property of being able to spread infection, used in medical and biological contexts.
このウイルスは感染性が非常に高い。
This virus is highly infectious.
感染性の有無を調べる必要がある。
We need to check for infectiousness.
伝染性 is often used for contagious diseases spread by direct contact, whereas 感染性 is broader and includes various routes of infection.
Compound of 感染 (kansen, 'infection') + 性 (-sei, '-ness, property').