Psychologists say there's emerging evidence of long-term and in some cases 'severe' effects from time spent in MIQ, brought on by a lack of control, autonomy and social contact.
While many returnees relish the two-week hotel stint, others say they're being caught completely unprepared by the mental health toll.
Debbie described her time in the Crowne Plaza hotel in July as being "stuck in a strange altered reality" where she had no idea how angry, distressed and "weird" she would feel.
"I really hit the bottom. I just sat and cried at the wire fence. I just couldn't move and I just felt like I couldn't do it - and this was only on day 2," she said.
"If it had been like staying in a hotel - I don't go to a hotel with an expectation of support. I just stay there, do what I have to do and I leave. I thought it was going to be that simple but it wasn't... it really is a strange reality of trying to fit into a set of rules, but you don't know what the rules are."
For Carrie-Ann it was a feeling of being lost and unmotivated - and she was still a bit rattled one month later.
Last month she and her three-year-old daughter spent two weeks in Auckland's Grand Mercure, following a trip to the UK to see her ill father.
Carrie-Ann expected it to be a relaxing few days, but the rest of the country went into lockdown and she started to panic about catching the virus after learning about potential transmission at the Crowne Plaza.
She said she struggled without opening windows and was fearful about turning on her air-con.
"I did break a few times in there. I can see how anybody's mental health would really struggle, especially people with kids. You're stuck in there trying to look out for the wellness of your children while you try to keep your own sanity," she said.
"You try to keep positive, but then I just had no motivation. And normally I'm quite active - I like to get out with my kids, doing things. All of a sudden I'm stuck in this room and I just had no motivation to do anything with my daughter. I felt like I was lost."
MIQ officials say there's a mental health clinician on hand at each hotel and nurses available 24/7, if returnees are worried about their own mental wellbeing or someone in their whanau.
The welcome pack given to returnees includes free support helplines, websites and services, while nurses are directed to ask about people's mental health and wellbeing as part of daily health checks.
But RNZ has spoken to several recent returnees who said that didn't happen at their hotels.
Debbie said staff seemed too overworked and too busy to check in on her mental health.
"Each day they took my temperature, checked for Covid-19 symptoms, and then left," she said.
Another returnee who left the Four Points by Sheraton today and asked not to be named: "I haven't been asked how I'm coping, just simply if we have symptoms... I believe there is supposed to be an on-site wellness team... I haven't heard from them once."
Clinical Psychologist Jacqui Maguire warned the impacts of MIQ on some people's mental health are "not to be underestimated".
She said a study by Kings College in London uncovered significant psychological impacts among people who'd spent more than 10 days in hotel quarantine.
In some cases the effects were long-lasting.
"It can increase stress and depression, it can worsen insomnia or bring on insomnia. It can lead to people being irritable, having concentration difficulties or feeling detached from others and for some individuals, especially those that may have an underlying foundation of mental illness or prior trauma in their life, it brings on symptoms akin to post-traumatic stress," she said.
"We should not be taking it too lightly."
Psychologist Dr Jane Millichamp said MIQ might seem monotonous and boring but it's stressful for humans to manage in a "state of limbo" with nothing to do and no social contact.
She said it was important for staff in the hotels to reach out and help people to stay socially connected.
"When people get a bit depressed and when they're feeling really low or very anxious, people don't always have the initiative to reach out. So contacting somebody or picking up the phone and ringing one of the counselling lines - that might not happen," she said.
"I think it would be really good if psychologists or mental health workers or nurses could maybe initiate the contact, especially with teenagers and young people."
Meanwhile, increased pressure on the MIQ system is also giving returnees another reason to feel less than okay.
When lobby group Grounded Kiwis surveyed 902 people who tried to get a spot in MIQ last week, those who were successful reported being well-aware of the thousands of others who'd missed out.
Spokesperson Alexandra Birt said it was upsetting to hear, given all New Zealanders should have the right to return home.
"There were people saying things like they were relieved, then immediately felt so guilty. And people saying they felt like they didn't deserve a voucher."
Jacqui Maguire wants the government to bear the mental health of New Zealanders in mind when it looks at the future options for MIQ.
"I think as a country, as our vaccination rates rise, we need to be really considered about where their 14 days in MIQ is the best option."
"We do know that this will be having a psychological impact on people - is MIQ'ing at home, for example, a better option providing both a physical and psychological health benefits?"
In the meantime, she suggested returnees go into MIQ with realistic expectations.
"If I'm entering MIQ and I know that it's a pressure cooker situation, you know I'm confined to a certain space, I've lost my ability to have autonomy in control over many things, my sense of freedom is diminished. They are significant triggers for poor well being. So if I know this actually before I enter, have I taken the time to problem solve how I'm going to manage through that period of time?" she said.
Jane Millichamp it can be beneficial to build a daily routine with online activities such as catching up with friends and family, yoga or physical exercise.
"Research has shown that allowing yourself to relax and be in the moment is a very good way to increase wellbeing and to reduce anxiety. So I usually recommend trying a free meditation app or mindfulness exercise off the internet."
Where to get help:
Need to Talk? Free call or text 1737 any time to speak to a trained counsellor, for any reason.
Lifeline: 0800 543 354 or text HELP to 4357
Suicide Crisis Helpline: 0508 828 865 / 0508 TAUTOKO (24/7). This is a service for people who may be thinking about suicide, or those who are concerned about family or friends.
Depression Helpline: 0800 111 757 (24/7) or text 4202
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Youthline: 0800 376 633 (24/7) or free text 234 (8am-12am), or email firstname.lastname@example.org
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