The Ministry of Health (MOH) has been notified of two genetically separate clusters involving a total of 18 individuals diagnosed with tuberculosis[1](TB) who had prolonged exposure at the Singapore Pools Bedok Betting Centre. The cases had immediately started treatment following diagnosis and are not a current ongoing public health risk[2].
2. The risk of transmission to persons who are not close contacts is very low. However, as a precautionary measure, officers from the Singapore TB Elimination Programme (STEP) will be contacting patrons who have visited Singapore Pools Bedok Betting Centre between 12 February and 25 March 2020 for TB screening. Screening will be conducted free of charge, at the Tuberculosis Control Unit (TBCU) (142 Moulmein Road). Voluntary screening will also be offered to former patrons who had spent prolonged durations (i.e. cumulatively days) at the Singapore Pools Bedok Betting Centre to watch live horse-racing telecasts between 2018 and 25 March 2020. Patrons who wish to be screened may call the TBCU hotline at 6258 4430.
3. In line with MOH’s TB prevention strategy, officers from STEP had earlier initiated contact investigations upon notification of each of the cases. Close contacts of all the 18 cases had already been identified and contacted by STEP for screening.
Identification of TB clusters
4. The two clusters were determined by genetic sequencing and epidemiological investigations which concluded in January 2021, as part of retrospective testing of TB cases to determine linkages. The 18 cases were diagnosed between February 2015 and October 2020. The link among five cases diagnosed between July 2018 and February 2020 was established and MOH was notified of the cluster on 28 July 2020. The 13 cases in the second cluster, who were diagnosed between February 2015 and October 2020, were notified to MOH between 1 December 2020 and 11 January 2021.
5. Investigations into the cases did not reveal any common links, other than that they had all frequently visited the Singapore Pools Bedok Betting Centre over a period ranging from months to years and spent prolonged durations at the centre watching live horse-racing telecasts. The cases did not know each other, and had not identified each other as close contacts.
Precautionary TB Screening beyond close contacts
6. While screening is not compulsory, MOH strongly encourages these individuals to be screened. Those with positive screening results will be offered appropriate advice and follow-up. Those with active TB will be treated immediately while those with latent non-infectious TB will be monitored and treated if necessary.
7. Screening for individuals who had visited the Singapore Pools Bedok Betting Centre or its vicinity, but did not spend prolonged time watching horse-racing telecasts, is assessed to be unnecessary due to the very low risk of transmission posed to such individuals.
Health Advisory
8. TB is typically spread through close and prolonged contact with an infectious individual, and not by contact with items or surfaces touched by a person with TB. Therefore persons who are contacted and screened following the detection of a TB individual typically comprise family members, close workplace colleagues and acquaintances from common social activities with close and regular interaction. This approach is recommended by the World Health Organization (WHO) and is practised in Singapore.
9. TB is endemic in Singapore and latent TB infection is not uncommon in our population, as TB had been prevalent in Singapore until the 1970s and older Singaporeans could have been exposed to TB and acquired latent TB infection when they were younger. Persons with latent TB do not experience symptoms of TB and are not infectious.
10. TB is curable and the spread of TB is preventable. Early detection and prompt treatment of cases remain important in helping those infected and rendering them non-infectious. For individuals diagnosed with active TB, adherence to treatment is important.
Annex A
[1] TB can be cured with anti-TB drugs. Treatment of active TB, which is sensitive to first-line anti TB drugs, usually involves a combination of different drugs, taken for six to nine months.
[2] Individuals diagnosed with TB will rapidly become non-infectious once treatment starts.