Articles: The Straits Times March 18, 2010 – The Forgotten Disease (pg 12-13)
The Straits Times March 18, 2010 – The Taming of TB (pg 14)
World Tuberculosis Day (24 March) is approaching once more; but tuberculosis seems to have become a “forgotten disease”! How much do you know about tuberculosis and its dangers?
Tuberculosis (more commonly known as TB) is transmitted from person-to-person by coughing or sneezing.[1] This produces “droplet nuclei” that are dispersed in the air. Each droplet nuclei contains one to three of the microorganism, Mycobacterium tuberculosis. Primary infection usually results from inhaling airborne particles that contain M. tuberculosis.1
Tuberculosis was a major health issue in Singapore in the post-war period during the 1950s and 1960s. Back then, there were more than 5,000 new cases yearly owing to high transmission rates of the disease coupled with few effective testing and treatment options available.
The Singapore Anti-Tuberculosis Association (SATA) was set up in 1947 to cope with the problem. By the 1970s and 1980s, treatment improved as more drugs were developed and became accessible. Enhanced understanding of the pathophysiology of the disease also allowed clinicians to develop more effective treatment algorithms. Health-care facilities also became better equipped with more screening and identification options. All of these factors seemed to indicate that tuberculosis would be on the decline. However, the number has risen again today despite how developed we are. 1,451 new tuberculosis cases appeared in 2008, the highest over the last decade.
When the microorganisms enter the body, the body’s immune system usually contains them and the infected person may not know that he has the latent form of disease. This is because symptoms will not show up unless the person’s immune system is unable to fend off the microbial attack. 1
Some symptoms include chronic cough (with sputum), unexplained weight loss, intermittent fever, night sweats and if serious, blood may surface in the sputum.[2] However, these symptoms are similar to many other ailments and thus, are often overlooked. While chest x-rays can be done, they do not point to a definite diagnosis.* Consequently, several tests may run to confidently diagnose tuberculosis.1 This process can take up to two months.
Once diagnosed, treatment comes in the form of a daily cocktail of pills. Depending on the severity of the condition, different drugs are used. Some anti-tuberculosis agents include Isoniazid, Rifampicin, Pyrazinamide, Ethambutol etc. Treatment can take up to nine months and it is imperative that patients adhere strictly to the drug regimen to prevent the development of drug resistance.
Despite the need for compliance, as many as 50% of all diagnosed patients fail to adhere to the prescribed drug regimen. Patients tend to become non-compliant once symptomatic improvement is seen. However, as the microorganisms have not been completely eradicated from the body, they can develop drug resistance.[3] This causes a rather serious complication subsequently as they are likely to manifest symptoms but by then, drug therapy would have become ineffective in dealing with the microorganism proliferation.
The World Health Organisation (WHO) has warned of a rise in multi-drug-resistant tuberculosis (MDR-TB) cases which cannot be treated with conventional drugs. Although the number of resistant cases have remained very low so far in Singapore (no more than four cases each in 2007 and 2008), this may change if more patients do not comply with their treatment. The fact that no new anti-tuberculosis drugs have been developed to deal with the mutant strains simply increases the chance for MDR-TB to proliferate.
Children younger than 2 years of age and adults older than 65 years of age have two to five fold risk for active disease compared with other age groups. Patients with underlying immune suppression (e.g., renal failure, cancer, and immunosuppressive drug treatment) have 4 to 16 times greater risk than other patients.[4] Such special populations are advised to seek medical advice if they find themselves with the symptoms mentioned above. If left untreated, one infected person can pass the germs to up to 15 others within a year. In 2008, 78 people here died from tuberculosis, accounting for one in 200 (0.5 per cent) of all deaths.
Preventing the disease from multiplying in the country is a difficult task given the inflow of foreign visitors and workers. As a result, the only viable way to stop the number of cases from rising again is to keep transmission rates down. SATA has done this by promoting community health through smoking cessation, health education sessions and health screenings.
As with any other preventive health measures, boosting the body’s immune system with sufficient exercise, sleep and nutrition lowers the risk of contracting the disease. Good hygiene practices such as washing of hands and covering of mouth when coughing can also limit the spread of disease. Compulsory BCG# vaccination for infants and children here has also kept the number of tuberculosis cases to a minimum. Nevertheless, it is still the social responsibility of every individual to minimise the threat of infection.
Pharmacists can play an important role in the prevention and treatment of tuberculosis. They can help ensure patient compliance by providing patients with more information about the drugs they are prescribed and how each drug can help them. Most importantly, they can press home the need for adherence to regimen.
Research pharmacists can also help develop drugs that are effective against MDR-TB as the drugs currently in use were developed in the 1970s and may no longer be relevant in MDR-TB cases. By pushing the frontier of modern medicine, it is hoped that they can better safeguard the health of our community and protect the world we live in.
Want to know more facts about Tuberculosis?
Find out more from the World Health Organization’s Tuberculosis page here
For facts closer to home, you can view the Ministry of Health’s FAQs page about Tuberculosis: here
Alternatively, for a quick overview of general facts about Tuberculosis, you may view the WHO’s Stop TB Partnership’s fact sheet for 2008 here
Picture Credits:
Stop TB Partnership (World TB Day Page)
Vaccination Guide for Children in Singapore
References:
[1] Iseman MD. A Clinician’s Guide to Tuberculosis. Philadelphia: Lippincott Williams & Wilkins, 2000.
[2] World Health Organization Report on the Global Tuberculosis Epidemic. Geneva: WHO, 1998.
* The clinician normally makes a diagnosis based on a combination of factors that include physical examination, clinical presentations, laboratory tests results and chest radiographs.
[3] Mahmoudi A, Iseman MD. Pitfalls in the care of patients with tuberculosis: Common errors and their association with the acquisition of drug resistance. JAMA 1993;270:65–68.
[4] Centers for Disease Control and Prevention. Meeting the challenge of multidrug-resistant tuberculosis: Summary of a conference. MMWR 1992;41:51–71.
#Bacillus Calmette-Guérin vaccination
Review done by: Winston Xu
Jolyn Seah
Pharmacy Year 1
