New Zealanders are being advised to keep their bubbles exclusive during alert level 3 in order to get through the COVID-19 pandemic "much more quickly".
Microbiologist Dr Siouxsie Wiles answered Kiwis' questions about the virus during a livestream on Tuesday and she says many people asked how they can expand their bubbles once level 4 lifts.
Her advice is unless it's a necessity, for example you need someone to look after your children while you're at work, then don't bring new people into your bubble.
"What's really, really important to understand is that those of us who don't have to expand our bubbles, that can stay home, must stay home. Because the more of us who do that, the less chance we have of the virus, that's still here, spreading to other people."
She says that her interviews with international media outlets have highlighted how "everyone is looking to us" to see how New Zealand responds to the virus.
"So my thing to New Zealand is let's not screw this up. Let's do this. If you don't have to expand your bubble, don't. It's just a few more weeks. If you do, it's all about thinking through how you can make sure that your bubble is still tight and small."
Prime Minister Jacinda Ardern announced on Monday that New Zealand will move from level 4 to level 3 on April 27 at 11:59pm. From there, level 3 will be in place for at least two weeks. Cabinet will then review how the country has tracked during that period and will make further decisions on May 11.
More businesses will be able to operate again, but no customers are allowed in shops. Hospitality stores can reopen only if they have a drive-thru, delivery or contactless pick-up system. Retail businesses can also open but only for online purchases or sending products to customers.
Wiles says level 3 is for opening up more of the economy, it's not about being able to physically socialise with others.
"It's that exclusive relationship. If you do really need to expand your bubble a little bit, then make sure that they're not expanding with someone else.
"The more of us who stay home the better, because we will get through this much more quickly."