The Canterbury District Health Board is assuring safety measures were in place when a guest from managed isolation visited a patient at Christchurch Hospital.
Another visitor, who was there on Monday, said they felt the guest, believed to be on day 12 of MIQ, put others at risk, and staff were not happy.
They claim the person was visiting a patient who was not critical or dying.
Canterbury DHB confirmed the visit took place.
Executive lead for Covid-19 Ralph La Salle said robust infection prevention control measures were in place to protect others.
He said those leaving MIQ have a transport plan, wear PPE and are required to return a negative Covid-19 test.
A Managed Isolation and Quarantine spokesperson said the threshold for exemptions is extremely high and very few exemptions are granted.
They also must return a negative Covid-19 test before they can go into the community.
"MIQ exemptions under the exceptional circumstances category cover requests such as the death of a family member or to visit a terminally ill relative. These applications are assessed on a case-by-case basis.
"The key factor in assessing an exceptional circumstances exemption application is the public health risk of transmitting Covid-19 to the community. Those applications that are approved are usually as a temporary pass out, when the applicant leaves the managed isolation for a short period of time and returns directly to the managed isolation facility."
The spokesperson said applicants must agree to strict release plans with travel provided with an approved escort, such as security or government personnel.
The strict release plan sets out where the individual will visit, and for how long. This includes keeping 2 metres apart from family and loved ones.