Now it is a full-blown world public health crisis, and probably the most serious such crisis of our lifetime.

No country and no person is immune from the disease and the old and infirm are particularly at risk. The biggest issue now is slowing the rate of growth so that our hospital system can cope with the rate of incoming cases for treatment.

We need to keep our distance from everyone in the coming months.

The reason why was explained to me by Dr Emma Gillmore, a Cloncurry GP who says we urgently need to slow the rate of COVID-19 infections.

COVID-19 infections are following an exponential curve, doubling so far in Queensland roughly every four to six days.

Using the power of multiples 2 becomes a thousand in nine iterations (roughly one to two months according to current infections), and a thousand becomes a million in another nine iterations (roughly three months from the start of the cycle).

Dr Gillmore says we urgently need to "flatten the curve" to slow the rate of cases so health facilities can cope.

"Say, one in a thousand people need intensive care, that is fine for our hospital system if there are just 100 people with the disease they can accommodate 1 extra person in ICU but if there are 10,000 cases - that is 100 extra ICU beds of which we do not have," Dr Gillmore said.

Dr Gillmore said survival rates would go down if a massive tidal wave of people get infected at the same time as we just simply cant provide the best level of care to everyone at the exact same time.

"This is an important time to be reminded of the power of hand hygiene and common sense in large crowd exposure," she said. "Flattening the curve" is now a textbook public health response to epidemics.

Once a virus can no longer be contained, the goal is to slow its spread.

Exponential growth leaves health care systems struggling. But with fewer people sick at a time services aren't overwhelmed and deaths diminish buying time to treat the flood of patients as researchers develop vaccines.