The US entertainment correspondent, 46, discovered she had tested positive as she prepared to go to LA.
She wrote on Instagram: “As I prepared to fly to LA to host E!’s Emmy coverage, I discovered that I, along with my husband Bill and our son Duke, tested positive for Covid-19.
“As you may know, the health of those around me is always my first priority.
“We are all three doing well and are isolating at home and taking very good care of one another.”
In a video message, Rancic said she was tested as part of the broadcaster’s “very strict testing guidelines”.
She said it would have been her “20th year on the E! red carpet” but added: “I’m very thankful i heard it before I travelled and possibly could have exposed other people and for that I’m thankful.”
And she said: “I’m doing well… We’re all doing well and taking care of each other.”
