Tuberculosis or ‘TB’ is still with us

A cough that will not go away should prompt you to get checked for tuberculosis or TB. Tuberculosis is an infectious disease caused by the germ Mycobacterium tuberculosis or Mtb that affects mainly the lungs. TB can also affect the spine (potentially leading to paralysis), the lymph nodes, or the covering of the brain (leading to meningitis). TB is spread through droplets when a person coughs or sneezes or breathes. TB may be missed by doctors and patients, with treatments being given for the common cold, flu, COVID-19, asthma, sinusitis, or allergies. This is because the signs and symptoms of TB may be non-specific, long lasting, or on and off. Anyone with a cough, weight loss, fever or night sweats for two or more weeks should be checked for TB. The disease reminds me of cancer, because of how it sometimes causes a hole to develop in the lung.

Many of us have been exposed to the Mtb germ, but we do not develop disease, as our immune system is able to keep the germ in check. Conditions and medications that weaken our immune system increase the chance of developing active TB disease. These conditions include HIV, cancers, and chronic diseases like kidney disease and diabetes. The immune system may also be weakened in persons who take steroids or strong immune suppressive medications to treat auto-immune conditions.

TB IS ALSO A SOCIAL DISEASE

TB is more common among persons living in crowded, unsanitary conditions with poor ventilation, including overcrowded dwellings, camps for refugees and displaced persons, and in closed settings such as prisons. Poverty and malnutrition increase the risk for TB, and for catastrophic consequences, including the inability to work due to the long period of treatment required and the need to be isolated from others to prevent spread.

How is TB diagnosed?

Good medical practice starts with interviewing the patient about their general health and the environment in which they live, work or spend a lot of time. Medications are available to cure TB, but the course of treatment is usually long, lasting at least six months for lung TB, for example. Failure to take the anti-TB medications every day as prescribed results in the Mtb germ becoming resistant to the medications, and more costly drugs and longer duration of treatment will be required.

A skin test may be used to check your immune system to see whether it has ‘seen’ the Mtb germ before. However, because Jamaica provides the TB vaccine at around birth, this can lead to a positive skin screening test, which does not necessarily mean that the person has active TB disease. The vaccine against TB is not one of the more effective vaccines, as it only seems to provide some protection against the spread of Mtb throughout the blood in young children, but not much protection thereafter. There is a blood test that screens your immune system with greater accuracy, although this is not currently widely available in Jamaica. It is currently offered only by the private sector. In addition, imaging tests, like chest X-ray are useful in picking up changes in the lungs that are associated with active TB.

The most useful tests are those done on sputum that is coughed up by someone with TB. The Mtb germ can be seen in the sputum using a microscope, or by tests that look for the genes of Mtb. The Mtb germ can also be grown from the sputum to help in diagnosing TB disease. Because no single test is perfect at diagnosing TB, the health team puts everything together and determines the likelihood that you have TB, and the risk of the infected persons getting worse or spreading it others.

Deaths from TB in Jamaica have fallen significantly from twelve deaths per million in the population in 1998 to two deaths per million in 2022. However, with about 80 cases of TB being diagnosed every year in Jamaica, we must maintain vigilance to prevent a resurgence, and eventually even eliminate TB.

Dr. Yohann White is medical director at Para Caribe Consulting. Send feedback to columns@gleanerjm.com, yohann.white@caribewellness.com or @CaribeWellness on Social Media.