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spread (e.g. of a disease); rampancy; infestation; proliferation; being widespread
ウイルスのまん延を防ぐため手を洗う。
I wash my hands to prevent the spread of the virus.
まん延する病気に対して予防措置を講じる。
Preventive measures are taken against spreading diseases.
情報のまん延が社会に大きな影響を与える。
The spread of information greatly affects society.