SingaporeCAAS on Twitter: "2️⃣ Testing: Take 2 COVID-19 Polymerase Chain Reaction tests. A pre-departure test within 48 hours before departing to Singapore and obtain a negative test result and an on-arrival test
SingaporeCAAS on Twitter: "2️⃣ Testing: Take 2 COVID-19 Polymerase Chain Reaction tests. A pre-departure test within 48 hours before departing to Singapore and obtain a negative test result and an on-arrival test
![Frontiers | Digital Contact Tracing Against COVID-19 in Europe: Current Features and Ongoing Developments Frontiers | Digital Contact Tracing Against COVID-19 in Europe: Current Features and Ongoing Developments](https://www.frontiersin.org/files/Articles/660823/fdgth-03-660823-HTML/image_m/fdgth-03-660823-g001.jpg)