MOH explains why 'MySJ Trace' triggers even when at home

COVID-19 | MySejahtera users who have activated its 'MySJ Trace' feature may find the application having interaction despite staying at home, as it detects other devices up to 10 metres away.

This is according to the Health Ministry's Crisis Preparedness and Response Centre's Head of Data Dr Mahesh Appannan, who today took it to Twitter to explain how the latest contact-tracing feature works.

"How could there be an 'interaction' despite staying at home? It is because Bluetooth signals can be detected up to 10 meters. Maybe your handphone is detecting (the phones of) your neighbours including those who live on different floors and adjacent units in an apartment," Mahesh Tweeted.

He was responding to another Twitter user who questioned about her MySJ Trace showing that she had eight interactions when she was at home while her parents have yet to activate the feature.

MySJ Trace is a feature that uses the phone's Bluetooth function to provide live information on interactions between close contacts, subject to access permission from the phone owner.

It was developed to help the health authority detect close contacts in the case of an outbreak, which is useful to control the spread of Covid-19 infection.

Mahesh said that while interactions may be recorded, it does not necessarily mean that a user would automatically be identified as a "casual contact" of a confirmed Covid-19 case.

This is because the algorithm used by the application also takes into account the strength of the signal.

Mahesh also reiterated MOH's assurance that users' privacy would not be compromised by using the feature, stressing that data is not shared every time there is interaction.

Instead, he said, the data would only be kept inside the user's handphone, and they will only be asked to share the data if they are found to be positive Covid-19.

"This is so that notifications can be sent to those considered as close contacts. This needs explicit consent.

"If you are not found Covid-19 positive, your data will not be uploaded, and would be deleted after 14 days," he said.

Mahesh said MOH strongly suggests that the public uses MySJ Trace on top of MySejahtera's check-in function because the latest function also analyzes distance between users, based on strength of the signal. - Mkini