Published Wednesday 30 Sep 2020

What are public health units, who works there, and what are they doing to stop the spread of COVID-19?

Since the beginning of the COVID-19 pandemic in early 2020, staff in public health services have been working hard to help protect New Zealanders from the spread of this new illness. The public may wonder: Where are these public health units, who works there, and what are they doing to stop the spread of COVID-19?

First, the facts. There are 12 Public Health Services in New Zealand. Staff are employed by District Health Boards (DHBs). Regional Public Health (RPH), based in Wellington, provides services to the Wairarapa, Hutt Valley and Wellington regions. The public health services also have direct links with the Ministry of Health.

Public health service work is often work ‘under the radar’ to improve the health of the population and prevent illness. Health promoters work at a community level on many initiatives including advocating for better housing, supporting smoke-free initiatives and improving access to nutritious food and healthier environments. The communicable disease teams work to reduce the spread of many infectious (notifiable) diseases, for example tuberculosis, meningococcal disease, measles and many others. The school team support the health of school children and deliver immunisations. The environmental health team works with councils and other agencies on safe drinking water, and improving our physical environment. The staff include specialist public health doctors and nurses, health promoters, health protection officers, analysts and managers.

The medical officers of health and the health protection officers are statutory officers. This means that they have legal powers under the Health Act and other laws, to protect the public’s health. Some of these powers are quite restrictive of people’s freedoms, for example ordering people to stay in a specific place while they are infectious. These powers are used only very occasionally, and with a lot of caution.

Contact tracing

Since the first whisperings of a potential global pandemic in early January 2020, the public health units, including RPH, have been in full preparation and response mode. The first case in New Zealand was on 28 February, and was followed by ongoing cases in travellers returning from overseas. These travellers seeded local outbreaks, often before they realised that they were infectious. The challenge with COVID-19 is that the virus is so infectious and people can pass on the disease even before they have symptoms. This increases the number of people that need to be rapidly contacted, tested, and advised.

Public health staff have to work very fast to interview the people with COVID-19, give them support and advice, and track down all of the people who could have been in contact with them while they were infectious. This process is known as ‘contact tracing,’ a concept that prior to the COVID-19 response, many New Zealanders will not have been familiar with. However, contact tracing is bread-and-butter work for public health nurses, who carry out the same process for cases of many different diseases. Contact tracing aims to establish a potential source of infection, and to look for close contacts who had interaction with a case while they were considered infectious.

After we are notified of a COVID-19 case we start with a phone interview. Details we need to know are the history of illness, travel, any contact with a known case. This helps us understand where they became infected. We then establish when the case would have been infectious and therefore could have shared the virus with others around them. This is the period of time we are most concerned with, and it is for this time we want to know all of their activities – where, when, with whom? Individuals who have had close contact with the case during this period are then followed up by us - provided with education about their exposure, the need to quarantine and then are followed up daily to review their health status. Other people who had less direct contact, for example who were in a supermarket at the same time, are considered ‘casual contacts’. Casual contacts do not need to be quarantined but they need to be alert for signs and symptoms, and tested if necessary. Obviously, all the work we do is carried out with sensitivity and the individual’s privacy as a priority.

It can be tricky for a person to recall what they did over the past days and weeks, especially if they are unwell. Sometimes it can take time and multiple phone calls to ensure we cover off all the potential places and people who may have been exposed. It’s a pretty time consuming job. One case could have had many activities in the period of concern – parties, café visits, university lectures, gym classes, dinners with friends, flights, buses, taxis and so on.

Liz MacDonald, Clinical Nurse Specialist, says:

The contact tracing aspect of our work is really interesting. It sometimes feels like you’re both public health nurse and private investigator as you work to track people down, and attempt to identify links between cases. Sometimes people choose to share some entertaining anecdotes with us and we find out what interesting lives people lead, even during their illness. We prefer people to over-share with us, in the pursuit of getting the most accurate information and again, the information people share with us is treated with sensitivity and the individual’s right to privacy at front of mind.

Supporting other Public Health Units

Auckland Regional Public Health Service (ARPHS) has been kept very busy, since the re-emergence of community cases of COVID-19 in Auckland in August. Regional Public Health, Wellington, and other public health services have been helping out with contact tracing for Auckland. A national database for cases and contacts has been developed this year by the Ministry of Health, so all public health units can see the same information. Once a case has been interviewed by the Auckland team, and contacts identified, the contacts are initially informed of the situation by a national team, and further daily follow up is undertaken by staff around the country.

Other ongoing COVID-19 activities for RPH include working with the Managed Isolation Facilities, where people returning from overseas stay for two weeks. We work alongside the DHB staff, border staff, defence and the hotel staff to ensure that all precautions are taken and that any new cases of COVID-19 are managed thoroughly and safely. We also work with the port and maritime authorities to ensure safety at the sea border. Our health promoters work to provide information and support to our communities which are less likely to access information through ‘mainstream’ communication channels.


This year has been challenging and rewarding for public health workers. It is important for us to always remember the ‘be kind’ mantra with each other at work, and while thinking about the people that we are working hard to support. Preventing COVID-19 is an all-of-society effort. The Māori whakatauki, or saying, is relevant to our work:Nāu te rourou, nāku te rourou, ka ora ai te iwi.With your food basket and my food basket the people will thrive. This whakatauki talks to community, to collaboration and a strengths-based approach. This is how we approach public health work, understanding that everybody has something to offer, a piece of the puzzle, and by working together we can all thrive.