Half of the country's district health boards are not using the Government's national contact tracing system for Covid-19 and experts are warning this could make it harder to control a future outbreak of the virus.
The 10 DHBs make up the four regional public health units that are not using the National Contact Tracing Solution (NCTS), including the country's two biggest - Auckland and Wellington - as well as Christchurch and Northland.
The NCTS is a cloud-based platform that stores all case and contact details, linked by exposure events, allowing anyone accessing the system to see the status of a particular case.
Effective contact tracing is critical to keep on top of the disease as the country moves rapidly towards level 1 controls. The Government has poured $55 million into developing a national software solution touted as essential in achieving that goal.
While Northland and Christchurch said they would likely use it in the future, Auckland and Wellington appeared reluctant to use it at all.
Auckland Regional Public Health Service (ARPHS) said it had developed its own software to manage multiple notifiable diseases, including Covid-19.
"This customised platform has been continuously developed over the past 12 years and is used in conjunction with the national Episurv system," it said in the statement.
While it was working with the Ministry of Health to determine how its system could work with the NCTS, it noted the national software "is currently for use only with Covid-19, while ARPHS system is used to manage a wide range of notifiable diseases".
Wellington's Regional Public Health Unit issued a similar response.
"Our system was adapted to include a Covid-19 case investigation and contact management module, in addition to other notifiable diseases modules [for example measles and whooping cough].
"We're working with the Ministry of Health to determine how our system will best interlink with the national system to ensure appropriate surge capacity, visibility of our local work at a central government level and connectedness with other public health units around the country."
Director-general of health Ashley Bloomfield told Morning Report that the DHBs bought onto the national system first were the ones without an electronic system.
He said he expected Northland DHB to come onto the system within the next few days.
Bloomfield said the large DHBs - Wellington, Auckland and Christchurch - already have systems that are sophisticated and interface with hospitals and primary care, so they need to make sure they're not losing any of the functionality they've built up.
He said those DHBs were working on a way to link their existing systems to the national interface.
Contact tracing experts told RNZ, on condition of remaining anonymous, there were compelling reasons why every public health unit should use the same software solution.
These included the ability to see what happens to contacts when they're referred to the National Close Contact Tracing Service, or another public health unit that might be picking up some of the work.
The NCTS also guided the user through a process to ensure the correct clinical process was being followed, and there were concerns that unless everyone used the same system, it would be difficult to share contact tracing efforts between public health units in the event of another outbreak.
The first report from the Contact Tracing Assurance Committee, recently appointed to oversee the recommendations from a report by Dr Ayesha Verrall, highlighted these problems and would be discussed with the Minister of Health today, RNZ understands.
Health Ministry ensuring it receives reliable data
The Ministry of Health said it was working with all four public health units (PHUs) to ensure they fed reliable data to the ministry while they were not using the NCTS.
It did not know when these four units would start using the national system, if at all, but it did not affect their ability to contact trace, it said in a statement.
"PHUs have well established existing systems and processes in place for contact tracing that they continue to use. Therefore, their contact tracing capability is not impacted by whether the individual PHU is using the NCTS.
"The NCTS provides a modern technology platform that supports an end-to-end view of all Covid cases and close contacts and ensures everyone undertaking contact tracing can have access to this view. All PHUs already have look-up access to the NCTS and can review the information associated with a case."