If on Tuesday you spent a few hours in a meeting with a colleague who today tested positive for coronavirus, you’d probably be spending some time in self-isolation from now.

That’s based on formal advice from the Federal Department of Health.

Their COVID-19 isolation guidance reads: “If you have been in close contact with a proven case of coronavirus, you must isolate yourself for 14 days from the date of last contact with the confirmed case.”

What constitutes close contact?

That’s defined on the government’s Health Direct website as being face-to-face contact for at least 15 minutes, or being in a closed space for two hours with a person who is infected with coronavirus.

But when is someone infectious? That’s a little less definitive.

The time between someone being exposed to the virus and developing symptoms is between five to six days, according to Health Direct advice. It could range from two to 14 days though. For that reason, “people who might have been in contact with a confirmed case are being asked to self-isolate for 14 days”.

The majority of coronavirus cases seem to spread from people who already have symptoms.

Although, two new studies out of Europe today suggest that's perhaps not always the case, and the virus is most contagious early on.

Home Affairs Minister Peter Dutton said he developed symptoms Friday morning, waking up with a temperature and a sore throat. He sought medical advice and was later today diagnosed with COVID-19.

In a statement, the Prime Minister’s office said advice from the Deputy Chief Medical Officer was that only those who had contact with Mr Dutton in the 24 hours before he became symptomatic need to be isolated or tested.

While Mr Dutton was at a Cabinet meeting on Tuesday, he attended a national security meeting yesterday via video link.

So, according to the Deputy Chief Medical Officer, there’s no need for the PM or other members of Cabinet to be concerned.

Is that consistent with public advice though? The PM’s office said it is.

“In advice provided to the Prime Minister this evening, the Deputy Chief Medical Officer has reiterated that only people who had close contact with the Minister in the preceding 24 hours before he became symptomatic need to self-isolate,” tonight’s statement said.

Confusing? Some might say so. Those that don’t have a Chief Medical officer on speed dial should continue to follow Federal Health Guidelines which state people must self-isolate if:

• You have left or transited through mainland China or Iran in the last 14 days

• You have left or transited through the Republic of Korea on or after 5 March 2020

• You have left or transited through Italy on or after 11 March 2020

• You have been in close contact with a proven case of coronavirus, you must isolate yourself for 14 days from the date of last contact with the confirmed case.

For more information check the Health Direct website.