Translation guide
This entry covers how to express the concept of becoming sick or falling ill in Japanese, from casual to formal contexts.
To say someone becomes sick or falls ill in a general sense.
The most common and neutral way to say 'to fall ill' or 'to get sick'. Used for both physical and mental illness.
彼は最近病気になった。
He recently fell ill.
I tend to get sick from stress.
More formal, often used in medical or written contexts. Means 'to develop an illness' or 'to become symptomatic'.
彼は先月発病した。
He fell ill last month.
Very formal, used in official reports or medical documents. Means 'to contract a disease'.
インフルエンザに罹患した。
I contracted influenza.
To emphasize the suddenness of falling ill, like coming down with something.
Literally 'to suddenly become sick'. Natural way to describe an acute onset.
昨日急に病気になった。
I suddenly fell ill yesterday.
Means 'to collapse' or 'to be taken ill'. Implies a sudden, severe onset that prevents normal activity.
彼は仕事中に倒れた。
He fell ill at work.
To say you caught a specific disease, like a cold or flu.
Pattern for catching a specific illness. Replace [病気] with the disease name.
風邪にかかった。
I caught a cold.
インフルエンザにかかった。
I caught the flu.
More casual pattern, often used for colds. '風邪をひく' is a set phrase.
風邪をひいた。
I caught a cold.
To express falling ill to the point of being confined to bed.
Means 'to be laid up (in bed) with illness'. Very common for describing being sick enough to stay in bed.
彼女は風邪で寝込んでいる。
She is laid up with a cold.
Literary/formal expression meaning 'to be confined to a sickbed'.
彼は長い間病床に伏している。
He has been ill in bed for a long time.
Use 病気になる for general illness or when the specific disease is unknown. Use 風邪をひく specifically for catching a cold. 病気になる can sound more serious than 風邪をひく.
昨日から病気で、熱がある。
I've been sick since yesterday and have a fever.
風邪をひいたみたい。
I think I caught a cold.
Do not translate 'fall' literally as 落ちる (おちる) when talking about illness. 'Fall ill' is an idiom; use 病気になる or similar expressions.