"Test, trace, isolate, support" – a Public Health intervention
6. To allow for a "test, trace, isolate, support" approach to work, the levels of disease need to be sufficiently low to make the management of outbreaks the exception rather than the rule. We have identified five steps for "test, trace, isolate, support" to be delivered effectively;
a. Effective disease surveillance. We need to understand COVID-19 in Scotland and identify patterns in disease activity, such as local outbreaks.
b. Early identification and isolation of possible cases. We need everyone to be aware of the symptoms of COVID-19, and understand what they need to do themselves to support our "test, trace, isolate, support" approach.
c. Early and rapid testing of possible cases. We are working towards ensuring that everyone who needs a test can get one, regardless of whether they can travel to a drive-through test centre, need to be seen by a healthcare professional, or can self-administer a test at home.
d. Early and effective tracing of close contacts of a confirmed case. This will involve people providing information about who they have been in close contact with, supported by dedicated staff as required and technology where appropriate. This process may start before the person has their test result.
e. Early, effective and supported isolation of close contacts. Chains of transmission can only be broken if those who could transmit the disease to others are isolated, and get the support they need to maintain that isolation.
7. The delivery of "test, trace, isolate, support" will be led by the NHS in Scotland. People who develop symptoms consistent with COVID-19 will be supported to isolate immediately and will be able to access testing.
8. Those who do test positive for COVID-19 will be asked to isolate for 7 days and their close contacts will be asked to self-isolate for 14 days. It will be important that the people identified as close contacts remain in self-isolation for the full 14 days. If they later start to develop symptoms, the process will begin again to test, trace, isolate and support any close contacts they have had while in the isolation period.
9. For the purposes of contact tracing, a close contact is someone who has been physically close enough to the confirmed case for a long enough period of time, that they may have had the infection transmitted to them. For COVID-19, this includes everyone who has been less than 2 metres away from a confirmed case for 15 minutes or more. The risk of the disease being transmitted is higher the closer the contact, the greater the exposure to respiratory droplets (for example from coughing), or the longer the duration of the contact.
10. The "test, trace, isolate, support" approach will be challenging to deliver as part of the response to COVID-19, because of some of the specific features of the disease;
a. The symptoms of COVID-19 are common, which means that at any time a relatively high proportion of the population may have symptoms, such as a cough or a fever – but they may not have COVID-19. Extensive testing will be required to confirm who has the infection.
b. Emerging evidence suggests that transmission can occur before a person is symptomatic. This means that it will be important to confirm cases through testing quickly, and we will need to trace the people a person spent time with before they felt unwell, as well as after their symptoms started.
c. Many people have very mild or atypical symptoms, or no symptoms at all. This means that it will not be possible to identify every possible case by symptom-based assessments, and it will not be possible to interrupt every possible chain of transmission. Other public health measures such as physical distancing and good hand and respiratory hygiene will remain crucial.
d. Transmission can happen in the course of normal and essential activities (e.g. speaking to people, touching contaminated surfaces). Contact tracing will need to adopt a risk based approach, prioritising the close contacts who are at greatest risk from transmission. We will reflect on international evidence and best practice in decisions about the approach in Scotland.
e. Isolation will be challenging. In order to interrupt chains of transmission effectively, we will have to ask close contacts, who may not even know the person with COVID-19, to self-isolate for 14 days. The success of this approach will therefore depend on the continued willingness of the population to do this.
f. We know that some people will find self-isolation for 14 days very challenging. We will work to ensure that support is in place to enable people to do this safely and to minimise the financial, social and wellbeing impacts.