Testing within the foreign worker population is currently being focused on dormitories with isolated number of cases.

"That's where the chances of success are greatest in terms of trying to disrupt the chain of transmission," said Ministry of Health's (MOH) director of medical services Kenneth Mak at a briefing on Apr. 28.

Shedding light on testing strategy at foreign worker dormitories, Mak said that it was being used beyond simply confirming an individual's Covid-19 diagnosis.

"We use testing a lot more strategically also to target those dormitories where we are intending to find out a little bit more about where the level of infection is."

In these dormitories where cases appear to be isolated rather than widespread, authorities have been conducting "active case finding" to identify the close contacts of confirmed patients.

These close contacts are then separated from the rest of the workers in the dormitory in order to limit the transmission of the virus.

Isolating first, testing later

Mak said that in the course of conducting tests at various dormitories, MOH had found some with only a small number of infections.

"Yet we've also seen in some dormitories, practically every foreign worker who presents to our medical team with symptoms of acute respiratory infection tests positive."

The priority in these dormitories with widespread infections was not mass testing.

Instead workers who are symptomatic are isolated, even if they have not yet been tested.

"The majority of them are very very well," he said, explaining that at isolation facilities there wasn't much more authorities to could do apart from monitoring their conditions.

The numbers will eventually catch up

Mak also confirmed that the daily reported numbers of new Covid-19 cases did not include these isolated workers who had yet to be tested, and may therefore be lower than the true number of infections.

However, he denied that this was an attempt to obscure the true number of infections.

"It's really a question of making sure that our priorities for testing match the needs that we have on the ground," Mak said.

He added that these symptomatic workers would be tested later, and that the numbers would eventually "catch up".

A MOH press release form Apr. 27, also listed testing migrant workers who have moved out of dormitories and working in essential services as an "urgent priority".

Top image by Sumita Thiagarajan and via MOM's website