Be/go down with something

Pro Tip 1/3

Temporary Illness

The phrase is often used for illnesses that are short-lived and not too severe.

Sorry, I can't join you for dinner; I've gone down with the stomach bug.

Pro Tip 2/3

Colloquial Use

It's common in casual conversation, but not in formal or medical contexts.

Many people in our office are going down with the flu these days.

Pro Tip 3/3

Not for Injuries

Used for diseases or infections, not for physical injuries like a broken leg.

I may not attend the party; looks like I'm going down with a fever.