A new local Covid cluster involving three cases in Singapore has been linked to an imported case who may have been reinfected in India before arriving in Singapore, news agency CNA quoted the country’s Ministry of Health as saying.
The cluster was identified through epidemiological investigations into a case where a 41-year-old accountant was confirmed to have the disease on April 16. Her husband, a restaurant manager, was confirmed to be infected on April 18.
The woman’s brother-in-law is an imported case, identified as a household contact of the woman and her husband.
The 43-year-old Indian national is a work pass holder and had arrived from India on April 2 and was asymptomatic then. He had tested positive for the disease in an on-arrival swab test, and had been taken to a hospital.
He was discharged from the hospital on April 6, without the need for further isolation as he was deemed to have been shedding minute fragments of the virus RNA, which were no longer transmissible and infective to others, the report mentions.
However, eleven days later, on April 17, the man was tested for the disease after being identified as a close contact of his sister-in-law.
His tests came back positive. “The Ct value of his PCR test taken on Apr 17 was lower than his test done on Apr 2, indicating a higher viral load this time,” said the Ministry, according to CNA.
“His antibody titres are also currently very high, suggesting that he was exposed to a new infection which boosted his antibody levels,” it added.
The Ministry said that in consultation with an expert panel comprising infectious diseases and microbiology experts, it was assessed that he was likely to have been reinfected with COVID-19 recently.
The Singapore government said it would closely monitor cases for reinfection amid emergence of new Covid-19 variants.