A cough is all it takes to infect a person

Dr Daniel K.C. Lee, a consultant respiratory physician at Prince Court Medical Centre, answers some questions on tuberculosis.

Question: How does a person get tuberculosis (TB)?

Answer: TB is usually transmitted through the air. One can get infected by being near a person who is suffering from TB. If the TB sufferer coughs out mycobacteria into the air, the healthy person could breathe in the polluted air.

Question: What happens when a person gets TB?

Answer: Healthy individuals are usually able to fight the mycobacteria on their own. BCG (Bacillus Calmette-Guerin) vaccination will also help battle the infection but it is not completely effective. It has become apparent over the years that BCG does not offer complete immunity against TB. A new vaccine is currently being developed.

A person who is exposed to TB does not necessarily go on to develop the disease. A person develops TB when his immune system is compromised, for example, when he is under extreme stress or is battling cancer, HIV or AIDS.

Question: What are the symptoms of TB?

Answer: The most common symptom is coughing, which is usually prolonged and produces phlegm. Some people will cough up blood. TB sufferers also experience fever, night sweats, poor appetite and weight loss. Others may have swollen lymph glands, usually around the neck.

Question: What are other risk factors?

Answer: Having contact with TB patients (it is always best to avoid anyone who is coughing or take precautions, such as wearing the N95 mask), compromised immunity (avoid being stressed, overly-worried, depressed or overworked) and unhealthy lifestyle (do not smoke or take illicit drugs or participate in risky behaviour).

Question: How is TB diagnosed?

Answer: Seeing a respiratory specialist is crucial. Clinical history is important and the chest X-ray is scrutinised. Other tests are the Mantoux skin prick test, QuantiFERON-TB blood test, sputum sample, bronchial lavage obtained from flexible fibreoptic bronchoscopy and CT scan of the chest.

Question: What could be the factors leading to the increase in TB cases in Malaysia?

Answer: This has been mainly blamed on the influx of foreign workers from Third World countries. Strict health screenings for foreign visitors is lacking.

Question: Is awareness of TB still lacking in Malaysia?

Answer: Yes. When someone has been diagnosed with TB, visitors to the hospital rarely take precautions, such as wearing masks. TB is highly contagious. A cough is all it takes.