SINGAPORE - The majority of those tested at an Ang Mo Kio HDB block where a cluster of multi-drug-resistant tuberculosis cases was found do not have TB, the Ministry of Health (MOH) said on Monday (July 4).
A total of 164 of the 223 current and former residents tested at a screening exercise conducted at the block tested negative and “do not require follow up”, MOH said.
But two residents of Block 203, Ang Mo Kio Avenue 3, have chest X-ray results which suggest possible active TB disease.
"They are currently being followed up for treatment, monitoring and contact tracing," MOH said.
Three residents had previously contracted TB earlier in life and had completed treatment, while nine others have yet to complete their screening.
Forty-five residents have latent TB, which is caused by past exposure to the bacteria. They are not infectious.
Latent TB is prevalent in Singapore, and this result is not out of the ordinary, MOH said.
About 22 per cent of those screened at Block 203 had latent TB. This is within the baseline prevalence anticipated -23 per cent - after accounting for the demographic profile and other factors, MOH said.
Those with latent TB "have no symptoms, do not feel sick and cannot spread TB to others", it added.
A screening was held at the block from June 16 to 19, and the results were sent to residents from June 30.
In addition, 12 current and former residents were screened at other clinics from June 20 to 30 and will receive receive their results soon, MOH said.
Last month, in what the ministry said was a "highly unusual occurrence", six residents in the block were diagnosed with the same strain of multi-drug-resistant TB over a four-year period.
Residents and former residents who lived in the block from July 2011 may continue to make an appointment to be screened for free at the TB Control Unit, MOH said.
They can also go to any Sata CommHealth clinic in Ang Mo Kio for a free screening.
MOH has been working with grassroots leaders in Ang Mo Kio to encourage residents to go for screenings.
A second round of visits were conducted on Saturday, and another letter will be sent to those who have not been tested, MOH said.
The Ministry also alerted nearby clinics and Ang Mo Kio Polyclinic to look out for residents from Block 203 who show symptoms of TB.