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Le malade reste en quarantaine pendant dix jours.
The patient stays in quarantine for ten days.
isolation to prevent the spread of disease
Les voyageurs sont placés en quarantaine.
Travelers are placed in quarantine.
the age of about forty, avoir la quarantaine
Il a la quarantaine depuis janvier.
He turned forty in January.
From quarante plus suffix aine, originally forty days of isolation.