Tuberculosis Situation and Measures

18 January 2012

Question No. 135

Name of person: Mrs Lina Chiam

Question

To ask the Minister for Health in the last 5 years (a) what is the number of (i) people infected with tuberculosis; (ii) students infected with tuberculosis; (iii) foreigners in Singapore infected with tuberculosis; (iv) adult Singaporeans infected with tuberculosis; (b) what is the current number of infected patients who are under treatment; and (c) what are the measures the Ministry has adopted so far to prevent an outbreak of this contagious and dangerous disease.

Answer

1. Please allow me to first explain the difference between active tuberculosis (TB) and latent TB infection. Active TB is a disease state where the patient is symptomatic and the disease can spread to others. Latent TB infection is an asymptomatic disease state during which the disease cannot spread to others. The majority of people with latent infection, about 90%, will not develop active TB disease. Only about 10% of persons with latent TB infection develop active TB disease and this may take place many years after the infection although there is a higher risk of active TB during the first two years of infection.

2. On average, about 1380 Singapore residents were diagnosed with active TB each year over the last five years, about 40 cases per 100,000. Most or about 95% of these cases are in adults. Among non-residents, excluding short-term visitors, the average number was also about 40 cases per 100,000 over the same period, or about 450 per year. Short-term visitors were excluded as many of them were workers who were diagnosed during pre-employment medical screening for application of work passes and would be rejected if they were found to have TB. Others were here specifically for TB treatment.

3. There were about 100 students diagnosed with TB each year during the last five years. More than 75% were in students aged 17 years or older.

4. About 1000 people are currently being treated for TB. I would like to highlight that Singapore has one of the lowest incidence rates of TB in Asia, beside Japan. Singapore has a comprehensive national TB control programme which was enhanced in 1997 with the setting up of the Singapore Tuberculosis Elimination Programme (STEP). Under STEP, the key control strategy for TB is firstly, early detection and effective treatment. This is important to stop the spread of TB in the community. Secondly, the TB Control Unit which runs STEP, closely monitors compliance to treatment until cure. While most patients would voluntarily be compliant with treatment, the Infectious Diseases Act gives us the power to mandate treatment of TB patients who are non-compliant if necessary. By actively monitoring the treatment progress of all active TB cases, the risk of treatment failure and development of multi-drug resistance are lowered. Finally, as TB could only be transmitted through prolonged closed contact, contact screening is conducted among household contacts and other close contacts in institutions like schools to identify persons with latent TB infection. Persons with latent infection are offered preventive treatment to reduce the likelihood of developing active disease.

5. My Ministry will continue to monitor the effectiveness of the TB control programme closely and implement enhancements from time to time.