A possible Covid-19 cluster has surfaced at Tan Tock Seng Hospital, with a nurse infected and likely infections in a doctor and three patients in a general ward.
The Ministry of Health (MOH) said one of the three new Covid-19 community cases yesterday is a nurse from Tan Tock Seng Hospital (TTSH).
The Filipino woman, 46, was deployed at ward 9D, a general ward.
She had a sore throat and body aches on Tuesday, and sought treatment at TTSH. She was diagnosed with Covid-19 the same day.
She had been vaccinated, and received the first dose of the vaccine on Jan 26 and the second on Feb 18.
The vaccine is effective in preventing symptomatic disease for the vast majority of those vaccinated, but it is possible for vaccinated individuals to get infected, said MOH in a statement.
TTSH locked down the affected ward, and tested patients and staff there. It found four more possible cases of infection. They are a doctor and three patients who were being cared for in the same ward.
As a precautionary measure, all staff who treated the infected patients, as well as all visitors, patients and staff working in Ward 9D, will be placed under quarantine, said the ministry.
Epidemiological investigations and contact tracing are ongoing.
As MOH is conducting further testing for these four cases, they have not been included in yesterday's case count, the ministry explained.
The Straits Times understands that one of the patients who tested positive for the virus is a 72-year-old woman who had been warded at the hospital since April 20.
She was admitted to the C class ward for rheumatoid arthritis, and developed a cough and fever on Sunday. Her symptoms persisted and she was tested for Covid-19 yesterday morning. The results came back positive in the late afternoon.
She has not received the Covid-19 vaccine. Her husband, son, daughter and a seven-year-old grandson who had visited her have been quarantined.
Generally, the incubation period for the virus is five to six days, but could also be as short as two days, or longer than 14 days. Patients can be infectious for a couple of days before symptoms appear.
In a Facebook post last night, TTSH said: "Visitors will not be allowed to the ward till further notice. As a further precaution, we are tightening our ward visiting policy till further notice, allowing only two pre-registered visitors throughout a patient's stay... We will also be swabbing all staff in the main hospital's ward block."
Another community case yesterday is an Immigration and Checkpoints Authority officer, 38, who works at Changi Airport Terminal 1. He had not gone to work after he started coughing last Friday.
The third community case is a Singapore man, 58, who returned from Nepal last December. He was detected when he took a pre-departure test on Monday to return to work in Nepal, where he is a construction project manager. He is asymptomatic. All three community cases are unlinked.