Source Investigation is being introduced by HSE Test and Trace today

HSE Press Release: Wednesday, 31st March 2021

As of today, Wednesday, 31st March, source investigation is being introduced by HSE Test and Trace as part of an enhanced testing and tracing service.

80 per cent of cases of COVID-19 are traced to a specific source through our Contact Tracing Centres or through HSE Public Health Teams. The remaining 20 per cent are classified as cases of community transmission. Public Health often re-classify these cases when they have the opportunity to contact the case again. This frequently reduces the 20 per cent community transmission figure downwards.

As of today, to support source identification efforts contact tracers will ask people with COVID-19, who are classified as cases of community transmission, extra questions about events or places they were at in the previous seven days before their symptoms began. 

If the confirmed case did not have symptoms, contact tracers will ask about events or places they were at, the week before the day of their COVID-19 test.

Source investigation is a core public health function in the investigation and control of outbreaks of communicable diseases. Conducting this activity, as standard, with the support of the contact tracers, aims to identify where transmission may have occurred in more cases.  We can use this information where possible to interrupt the chains of transmission. It will provide real-time information about events and situations of where the virus is spreading to Public Health Teams. Public Health Teams may then decide to offer testing to people that were at the same venue or setting at the same time as the case, to stop further spread of disease and prevent clusters of COVID-19 developing in the community.

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Last updated on: 31 / 03 / 2021