On March 20, 2020, the Government Technology Agency (GovTech) in Singapore released TraceTogether, which uses Bluetooth technology to notify users when they come into contact with COVID-19 patients.
The app is designed to expand existing contact tracking efforts so that authorities can quickly identify and quarantine close contacts of COVID-19 patients.
Since its inception, TraceTogether, using the BlueTrace protocol, has amassed more than two million users – roughly one in three people living in Singapore.
However, experts believe that TraceTogether needs to be downloaded by a larger section of the Singapore population for the app to have a significant impact on contact tracking.
One problem that affects the effectiveness of TraceTogether is the fact that it doesn't work well on Apple's iOS operating system.
TraceTogether needs to run in the foreground for it to work most effectively, contradict user behavior, and shorten battery life.
To get around this problem, tech giants Apple and Google recently partnered to launch Exposure Notification (EN), a protocol that can run on both iOS and Android systems.
“Each protocol has its own strengths. Both are trying to do the same, but have different limitations, ”said Harish Pillay, chief technology architect at open source software provider Red Hat.
We determine the reasons why TraceTogether is better suited to the needs of Singapore.
Catering for the local context
It is important to note that TraceTogether was specifically designed to support the Department of Health's (MOH) response to a public health crisis – to intervene and quickly control the spread of the coronavirus.
(The app) provides contact tracers with additional information so they can locate infected contacts more quickly, reduce the spread of the disease, and give the population more freedom to move, work, and socialize than would otherwise be possible.
– Roland Turner, chief privacy officer of the relationship analysis provider
Once confirmed that a user is infected with COVID-19, they can upload the TraceTogether Bluetooth data.
From there, MOH contact tracers can decrypt the list of close contacts and quickly place quarantine orders. All IDs are encrypted to protect user data. Only MOH retains exclusive access to the identification key.
However, some have raised questions as to why the government has not used the EN protocol, as this would result in greater acceptance among iOS users and higher acceptance would mean better contact tracking.
In a Facebook post on June 15, the minister responsible for the Smart Nation initiative, Dr. Vivian Balakrishnan: “While it is a good and innovative system, we have decided that it is less effective in the local context. ”
Credit: Vulcan Post
Determination of the source of infection
First, EN ultimately relies on users to be responsible by monitoring their own symptoms and uploading their data to the cloud if they can get by with COVID-19.
Second, EN should withhold certain information from health authorities such as the MOH.
In a situation where three infected people A, B and C come into close contact with three other people X, Y and Z, EN X, Y and Z would inform them that they may have been exposed, but would not be able to see if the exposure was associated with either A, B or C.
While EN MOH allows knowing who the potential close contacts of the infected person are, contact tracers cannot identify how, when and who infected the person at all.
Without this information, MOH contact tracers cannot accurately identify the transmission chain, determine the exact source of infection, and check which close contacts were actually exposed to COVID-19.
"The cost of this limitation is a greater spread of disease because there is no experienced contact tracer in the loop," said Turner.
Photo credit: GovTech
"It appears that COVID-19 is a more complicated disease than EN was developed," added open source activist Dr. Andrew "Bunnie" Huang added.
“In particular, EN cannot determine the cause of infections. Asymptomatic carriers may receive numerous notifications that they have been exposed to COVID-19 even though they have actually exposed others to the virus. "
– Dr. Andrew "Bunnie" Huang, open source activist
Based on the statement by Dr. Huang, firmware developer Sean "xobs" Cross concluded, "The exposure notification protocol is not enough to support contact tracking."
On the other hand, Dr. Huang states that TraceTogether's BlueTrace protocol has the potential to uncover the cause of infection or causality – but only if there are enough participants in the network. Therefore, improving the accessibility of TraceTogether has top priority.
Accessibility from TraceTogether
However, since about one in five Singaporeans still doesn't have a smartphone, TraceTogether has to be more than an app to achieve a greater range.
Not everyone can afford a smartphone, and older smartphone models or operating system versions don't do the BlueTrace or EN protocol well. To ensure effective protection for as many people as possible, we had to consider (hardware) tokens that are simpler, more effective, and more convenient than phones.
– Dr. Vivian Balakrishnan, Foreign Minister and Minister responsible for the Smart Nation Program Office initiative
A new portable device called TraceTogether Token will help address some of the challenges the mobile app faces, such as: B. the need for maximum effectiveness and battery consumption.
However, such an option would not have been possible with EN, which is limited to the iOS and Android operating systems.
TraceTogether and the underlying BlueTrace protocol are a native solution that is tailored to the needs of the country. They are an example of how technology can be used to support a very human endeavor – the specialized and professional work of our contact tracers.
This article first appeared on GovTech. You can also get byte-sized (geddit?) Technical stories from GovTech Here.
Selected image source: AFP / Vulcan Post