Both Locally Transmitted COVID-19 Cases Reported on 26 Apr Could’ve Been Past Infections

One of the difficult things about contact tracing is that a COVID-19 infection doesn’t come with a timestamp.

So, if you’re infected with the virus, you won’t know when you got infected or when you recovered.

Even if you test positive this month, for example, you may have even got infected months ago. 

And that’s what may have happened to the two locally transmitted COVID-19 cases reported yesterday (26 Apr).

Dormitory Resident Who Tested Positive May Have Gotten Infected Last Year

One case was in the community, while another was in a migrant workers’ dormitory.

The migrant worker who tested positive for the coronavirus lives at Westlite Woodlands dormitory, the site of a growing COVID-19 cluster.

However, the authorities believe the 35-year-old Bangladeshi contracted the virus abroad.

This is because the men from the cluster who previously tested positive live in a different block and had not interacted with the man.

The 35-year-old is employed by Jenta Decoration Contractor as a construction worker but does not typically interact with clients.

The work permit holder was in Bangladesh from 17 February to 21 December last year, after which he returned to Singapore and served a stay-home notice (SHN) at a dedicated facility from 21 December to 4 January.

A swab test on 1 January came back negative, as did the several tests he subsequently took as part of rostered routine testing.

The last of these tests was on 20 April.

Two days later, the man was quarantined as part of the precautionary measures taken following the detection of another case in his dormitory.

Then, on 23 April, the man was tested and this time the result came back positive. He was taken to the National Centre for Infectious Diseases (NCID).

Curiously, the man then tested negative just two days later. 

The authorities believe he was infected while overseas and that he’s now shedding minute fragments of the virus RNA which are no longer transmissible and infective to others.

This theory is supported by his serology test result, which came back positive and indicates a past infection.

Authorities Believe 19YO Community Case is a Past Infection

The sole community case reported yesterday (26 Apr) is a 19-year-old student who studies in the United Kingdom (UK) and returned to Singapore last December.

Last year, she had been in the UK from 11 September to 1 December.  She said she experienced acute respiratory infection symptoms while in the UK in September, but was not tested for COVID-19 then.

She then returned to Singapore and served her SHN, during which she tested negative for COVID-19.

Then, on 23 April, the 19-year-old took a pre-departure test in preparation for her trip to the UK and tested positive.

Just like the 35-year-old Bangladeshi, the Ministry of Health (MOH) believes this could be a past infection, as her serology test has come back positive too.

“She could be shedding minute fragments of the virus RNA from a past infection which are no longer transmissible and infective to others, but given that we are not able to definitively conclude when she had been infected, we will take all the necessary public health actions as a precautionary measure,” MOH said.

Both cases are currently unlinked.

Feature Image: kandl stock / Shutterstock.com