In an unassuming office building in Woden, a group of dedicated "disease detectives" are on the COVID-19 case. There's no PPE and much of their work is done over the phone, but it's lifesaving stuff. It's their work - along with the public's cooperation - which will determine whether Canberra's health system will be able to manage the pandemic, or whether there will be scenes reminiscent of New York and Milan. They are the team behind the ACT's extensive contact tracing. The method is old school but tried and tested, and in the absence of a vaccine provides the best chance of suppressing the virus to sustainable levels.
The best defence
The principles of contact tracing are simple. Find a case, isolate them from the community and meticulously trace their steps to find people they came in contact with. Successfully completed tracing can be the difference between a full blown outbreak and the virus being well managed. The work of contact tracers came into the spotlight last week when Prime Minister Scott Morrison said contact tracing would be "beefed up" to industrial levels across the country. It would only be then - as well as when the health system was strengthened and testing extended - that some social distancing restrictions may be eased.
Epidemiologist and ACT Health operations team leader Tim Sloan-Gardner says it was only through contact tracing a full picture of the outbreak could be captured. While no one working in public health has experienced an epidemic on the scale of coronavirus, the principles they are applying are the same for any other pathogen. Sloan-Gardner says public health workers anticipated a pandemic at some point, expectingit to be of zoonotic origin like a flu or a coronavirus. "I don't think you can ever be prepared for a pandemic, and I think it's pretty clear we were never prepared for something of this scale internationally either. No one expected it to get this big so quickly," he says.
Public health registrar Dr Naomi Clarke says contact tracing is the bread and butter of public health units. "It is not a new skill, you obviously have to adapt the approach as you learn more about any given bug," she says. "But these are the skills that our staff know. They're very skilled in contact tracing and we're getting new staff and training them, but this is not a skill that's specific to COVID-19."
When tracing the steps of a confirmed case, contact tracers aren't looking for a person they may have passed on the street, or the supermarket worker who briefly served them behind a partition. To be regarded as a close contact of a confirmed case, and therefore required to isolate, the person needs to have been in face-to-face conversation with the patient for 15 minutes, or have spent two or more hours in an enclosed space with them. The public will usually be informed about a case's presence at a public event if they spent a significant amount of time there. "So it's about balancing the risk and the need to inform the public," Sloan-Gardner says.
The contact tracing team has had to expand rapidly and is drawing on all the expertise it can. Medical students have been trained up to help out if needed, while nurses from units that are no longer working at full capacity due to the epidemic are being redeployed. The Australian Defence Force is also assisting.
On the case
When a test returns a positive result, the contact tracers are immediately contacted by pathology. They are then responsible for calling the case and letting them know the result. The tracers get a variety of responses - from surprised to anxious - but have been pleased with how cooperative people have been.
Case manager and public health nurse Sue Reid says they will go through the patient's symptoms to find out when they likely became infectious, and when they started to feel unwell, to determine a possible source of infection. They then begin retracing the case's steps to find out where they may have spread the virus.
"We really drill quite deeply into that," Reid says."It's not like basic movements, it's more like a day to day, sometimes even minute to minute. You might say to somebody, well were you in a coffee shop? Who did you sit next to? Some of our investigations have been quite protracted. "It's really about getting their trust as well ... so it can take some time."
One of those complicated investigations finished on Friday, and the team concluded a source of the infection was not able to be found. That case is now considered the ACT's first case of local transmission. Once the team has received all the details possible from the case, the information is sent to a contact tracing team who meticulously track down anyone who was in contact with the case.
There can be hundreds of people at any one time the team is trying to find to determine who needs to isolate to stop the virus in its tracks. After 14 days with no symptoms, cases are generally allowed to leave isolation, but health care workers are usually required to take a test to make sure. "While we are doing a really great job of flattening the curve, leaving one contact un-contacted could then result in onward transmission," Clarke says.
The team will also cross reference with the patient's close contacts, to make sure they haven't omitted any movements. The team has to apply some real detective work to track some people down. For example, they were only given email addresses for some of the recent cruise ship arrivals in the ACT. "We work really hard [to find people]. Sometimes you might have a mobile number that doesn't work. And we have to really work hard to think about ways we can contact these people. It may sound like it's just one person, but that one person may be in touch with dozens of other people," Clarke says.
An emotional toll
The work can get personal. While they never meet the cases face to face, after knowing detailed accounts of their life and having ongoing interactions with them for weeks, they often feel like they really know the patients. There have been three deaths so far in the ACT, and all have hit the tracers hard. They're also responsible for looking out for the welfare of those told to isolate. "These people could be at home on their own," Sloan-Gardner says. "So do they have appropriate accommodation, do they have access to food, do they have access to regular medications that they need as well?"
Reid says the cases often just appreciate the calls. "I think you really build up a rapport with them," she says. "Sometimes they just really need a chat, and there are people who are on their own and don't have anybody at home so that can be quite lonely and isolating for them."
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