Translation guide
The English word "infection" covers both the process of becoming infected and the resulting illness. In Japanese, different words are used depending on whether you are talking about the medical condition, the act of transmission, or a wound becoming infected.
To refer to an infection as a disease or medical condition, such as a bacterial or viral infection.
The standard medical term for an infectious disease. Used in formal and everyday contexts.
新型コロナウイルス感染症が世界中に広がった。
The novel coronavirus infection spread throughout the world.
感染症の予防には手洗いが大切です。
Hand washing is important for preventing infections.
Often used as part of compound words or in the context of the act of becoming infected. Can also refer to the infection itself, but 感染症 is more common for the disease.
傷口から感染が広がった。
The infection spread from the wound.
To describe the process of catching an infection or the spread of pathogens.
Refers to the act of being infected by a pathogen. Used as a noun or as part of the verb 感染する.
ウイルスに感染しないようにマスクを着用してください。
Please wear a mask to avoid getting infected with the virus.
彼はインフルエンザに感染した。
He caught the flu.
Emphasizes contagion or transmission from person to person. Often used for highly contagious diseases.
To refer to an infection in a cut or wound, often with pus or inflammation.
Specifically refers to suppuration or the formation of pus in a wound. Commonly used in everyday language.
傷が化膿して痛みがひどくなった。
The wound became infected and the pain got worse.
Can also be used for wound infections, but 化膿 is more specific when pus is present.
To refer to a computer or device being infected with malware.
The standard term for a computer virus infection. Used with ウイルスに感染する.
パソコンがウイルスに感染した。
My computer got infected with a virus.
感染 (kansen) refers to the act or process of infection, while 感染症 (kansenshō) refers to the infectious disease itself. Use 感染症 when naming a disease (e.g., 新型コロナウイルス感染症), and 感染 when describing the transmission or state of being infected.
For infected wounds with pus, 化膿 (kanō) is more natural than 感染. Saying 傷が感染した is understandable but 化膿した is the common expression.
この病気は伝染力が強い。
This disease is highly contagious.
傷口が感染して赤く腫れている。
The wound is infected and red and swollen.