SINGAPORE: The majority of people screened for tuberculosis (TB) during screenings conducted by the Communicable Diseases Agency (CDA) earlier this month in Bedok have tested negative for the disease.

A total of 3,169 persons were screened for TB during the screening process from May 2 to May 8 – with 85.1 per cent testing negative.

The remaining 14.9 per cent or 473 individuals have tested positive on their blood test and require a follow-up chest X-ray to determine if they have active TB or latent TB infection (LTBI), the agency said in a press release on Wednesday (May 13).

"The vast majority of these individuals are expected to have LTBI, which means they do not exhibit symptoms of TB, are not infectious, and therefore do not pose a public health risk," CDA said.

The agency said the positivity rate of 14.9 per cent is within expectations, given the presence of transmission clusters detected at the three locations, and the high proportion of elderly in the area.

The three locations referred to are: Heartbeat@Bedok, Block 216 Bedok Food Centre & Market and the Singapore Pools Bedok betting centre, where investigations found 13 genetically similar cases across three clusters between January 2023 and February this year. 

The screening done by CDA was for tenants, workers and those who frequented these locations.

CDA noted that the latent TB prevalence among all Singapore residents was 12.7 per cent in 2015. The prevalence of LTBI increases with age, ranging from 2 per cent among persons aged between 18 and 29 years old, to 29 per cent among those aged between 70 and 79 years old, it added.

CDA emphasised that a positive blood test result does not mean a person has active TB disease.

"The blood test indicates whether a person has been exposed to the TB bacteria, and a further chest X-ray is needed to determine their actual health status," it said.

"Most are expected to have LTBI, which is not uncommon in Singaporeans."

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