A new test, developed by Duke-NUS Medical School, that can detect coronavirus infections even in recovered patients, had been used to link Singapore's biggest virus cluster at the Grace Assembly of God church and the cluster at The Life Church and Missions.

On 25 Feb, MOH said that it determined the primary case in the Grace Assembly of God cluster was case 66, who works at the church. Investigations showed that he had attended the same Chinese New Year gathering on 25 Jan as cases 83 and 91. Contract tracers found that the married couple had gone to the Life Church and Missions on 19 Jan, the same day as cases 8 and 9 – Chinese nationals from Wuhan who tested positive for COVID-19 in late Jan.

Health Minister Gan Kim Yong said that the discovery of case 91 as the missing link between the two clusters was good news as it meant that there is a greater assurance that these two clusters are within control.