On Saturday (Feb 6), the MOH said the 28-year-old male Bangladeshi national holds a work permit and resides in a dormitory at 43 Tech Park Crescent.
He had been confirmed to have Covid-19 infection on April 12 last year and subsequently recovered, consistently testing negative for the infection from June onwards.
But on Jan 25, his test result came back positive for Covid-19 infection, and he was isolated.
Numerous repeat tests conducted subsequently were also positive for the virus.
He was identified from rostered monitoring testing conducted as part of the MOH's surveillance of recovered workers to monitor their post-infection immunity.
He reported that he felt unwell on Jan 22 and 23, but was otherwise asymptomatic.
The MOH said that while reinfection is rare, the expert panel, which comprises infectious diseases and microbiology experts from the National Centre for Infectious Diseases, Singapore General Hospital and the National Public Health Laboratory, assessed that the clinical and laboratory evidence suggests this is a likely case of reinfection.
The MOH added: "In addition to his positive polymerase chain reaction (PCR) test results, there was a corresponding marked increase in antibody titres compared to the period prior to the likely reinfection, suggesting that he was exposed to a new infection which boosted his antibody levels."
It also noted that the virus detected in his samples taken in January this year is also genetically distinct from that associated with the dormitories outbreak last year, suggesting this is likely a different and new infection.
"MOH will continue to closely monitor recovered Covid-19 cases to determine their post-infection immunity. So far, there is no indication that recovered workers in the dormitories have significant loss of post-infection immunity," the ministry said.
On Saturday, the MOH reported 26 new cases, all imported. There were no new cases of locally transmitted infection.
Overall, the number of new cases in the community has decreased from three cases in the week before to one case in the past week.
The number of unlinked cases in the community has also decreased from two cases in the week before to one case in the past week.
Published : February 08, 2021
By : Sue-Ann Tan The Straits Times/ANN