SINGAPORE - The Covid-19 viral strain that caused the cluster at Block 506 Hougang Avenue 8 has been found to be the same as the one detected at other blocks in the vicinity.
This points to either a common exposure to the virus or some people being initially infected and then subsequently spreading it through their household or via common areas such as lifts and staircases, said Singapore's director of medical services Kenneth Mak on Thursday (June 10).
"It does not necessarily mean that the virus has spread through sewage systems or even airflow," he said at a virtual press conference by the multi-ministry task force on Covid-19.
But investigations are still ongoing, and the Ministry of Health (MOH) has yet to arrive at a firm decision on what the mode of transmission is. It is also looking at the other cases that have arisen in neighbouring blocks. Tests suggest that the viral strain for these infections is the same.
The genome of the virus is first sequenced before a phylogenetic analysis is done on it, which allows for cases to be linked to clusters and variants of concerns to be identified.
"We are also focusing on the blocks around Block 506… The initial testing we did was for that particular block, but we've extended it now, as we have also picked up other cases in the vicinity," Associate Professor Mak said.
Block 506 Hougang Avenue 8 was first announced as a new cluster by MOH on June 3. A special testing operation was also carried out at the block on May 21 and 22 after the earlier cases were detected.
It was also previously reported that Covid-19 viral fragments were detected in wastewater samples collected from Blocks 501 and 507 Hougang Avenue 8.