(This post is contributed by a PHAA member working in the NSW health contact tracing team)
The phrase ‘contact tracer’ much like ‘epidemiologist’ or ‘Public Health Order’ is a term that previously was rarely used outside of Public Health circles. Now a year and a half into a worldwide pandemic it has become part of our common dialogue. But what does the phrase mean and what does work in the role look like?
Described often in the media as ‘disease detectives,’ contact tracers work to identify, assess, and manage people who have been exposed to COVID-19. Together with other infectious disease control methods, contact tracing can work to detect and break trains of transmission.
NSW takes a decentralised approach to public health. With eight local health districts covering the Sydney metropolitan region and seven covering rural and regional NSW, all of which sit under the umbrella of the state’s ministry of health. Working within one of the local health districts contact tracers work with an experienced team of public health medical officers, and public health nurses to minimise the transmission of COIVD-19.
The first major component of contact tracing is case interviews. Case interviews involve downstream and upstream contact tracings as well as linking the patient up with clinical and welfare support, which they will need access to while they are unwell and isolating.
Downstream contact tracing involves identifying where the case has been during their infectious period. An individual’s infectious period is calculated as two days before symptom onset, or two days before the positive swab in an asymptomatic case. This process identifies potential COVID-19 exposure sites and identifying close contacts.
Upstream contact tracing is about discussing with a positive case about where they have been before their infectious period to try and identify a source. In cases where an individual has been identified as a close contact already or linked to a venue of concern this process is quite straightforward. Other times when no known source is clearly identifiable this needs to be pieced together through an interviewing and testing of the contacts of the cases to see if any links can be established.
Try to think about all the places you have been in the past two and half weeks and you can see how this can become quite an extensive process! Using tools such as QR code check-ins, photos from the cases camera roll, banking statements, calendars, and diaries to piece together the story of the individual’s movements to try to identify an exposure site or interaction with a source case.
An equally important part of the case interview is ensuring that the case is linked up with appropriate health services to follow up the clinic management of their care. This ranges from virtual healthcare through clinical nurses and doctors, psychological support, welfare support and cultural support.
The second major component of contact tracing is venue assessments. This involves getting in touch with all venues visited by positive cases throughout their infectious period. Venue risk assessments involve discussion with the venue owner or manager to assess the level of risk to staff and patrons from the positive case exposure. This process may involve consulting with CCTV footage, QR code check-ins and staff lists. The nature of this risk assessment will change based on the health advice at the time and the stage in the outbreak response we are in.
Definitions for close and casual contacts from these venues are constantly evolving based on the best health advice at the time. In particular, with the recent Sydney delta outbreak definitions have changed rapidly and these reflections shift to match this. Venues of particular concern include health care facilities, hospitals, and vaccination hubs. Extensive risk assessments involving a team of clinicians are often included for venues of this nature.
Venue assessments also involve discussion with the manager or supervisor about media exposure, identification of staff and customers who were visiting at the time. And finally discussing the protocol for deep cleaning and assistance and advice for this process to ensure the venue is safe to re-open the next business day.
The third major component of contact tracing is getting in touch with close contacts. Normally at a district level, this involves contacting household and social contacts of cases. While venue level close contacts are referred to the NSW Ministry of Health who have an entire dedicated close contact tracing team who work exceptionally hard to contact all of these individuals.
Close contact calls involve discussing the isolation requirements for the identified individual for the 14 days post-exposure to the positive case. Major considerations include the individual’s capacity to successfully isolate at home, including how many bedrooms and bathrooms they have, how many people they live with and if alternative accommodation needs to be arranged.
Additionally, we discuss the covid-19 testing regime for the close contact, the dates that the individual needs to be tested, if they can access a testing clinic without using public transport or if testing needs to be arranged to visit them.
Another vital aspect of this discussion involves referring the close contact to the close contact tracing team for follow up throughout their isolation. Concerns about psychological support, welfare support and cultural support are all also identified in this interview to ensure that the individual has access to everything they need to isolate effectively and safely.
While this is a generalised overview of what contact tracing involves every single case is unique and definitions and protocols are constantly changing based on the newest medical advice! No two days ever look alike.