The rules for self-isolation for those who are coming back into the country pose a significant problem - and if it's not dealt with soon it could be costly in so many ways.

The man with arguably almost as much power as the Prime Minister these days, Ashley Bloomfield, was - in the first of his many outings this week - defending the treatment of arrivals at the border, which has rightly come in for harsh criticism.

If the figures up until now are to be believed, that most of those who've caught the deadly virus have done so through contact with Kiwis coming home, it's difficult to see how the self-isolation is actually working.

At the outset, Jacinda Ardern said trusting the arrivals to do the right thing and stay at home would be enhanced by their being picked up at the airport and not catching a taxi.

Bloomfield's latest definition of self-isolation from this group fails right there, at the airport. He expects them to go home and self-isolate for 14 days from anyone else who happens to be living in the house.

Short of getting into the boot at the airport, one would have thought the damage would have already been done by the time they get home.

Contrast that with those who come back and who have made no self-isolation plans. They're taken to monitored accommodation, such as a hotel, and are kept there for the required time.

Surely it's better for all of us, if we are determined to stamp out this virus, or at the very least contain it, to quarantine them all at the border. Anything short of that, as we've seen by the contamination figures, is a failure.

Spending the money now on forced quarantine to ensure the virus isn't going to be spread in the way it has been by those returning home will not only ensure the country can safely emerge from this before cabin fever really takes over, it'll turn the business lights on again, although they are likely to be on the dim mode for some time to come.

There have been some positive signs from Jacinda Ardern, with her telling breakfast television that more border restrictions could be on the way and may be announced this week, saying there are still areas that have to be worked on.

Hearteningly, she said she wanted to move a step up, which hopefully will finally be a step in the right direction.

And not a moment too soon, considering hundreds of desperate Kiwis are about to hit our shores on mercy flights.