Coordinated and inter-sectoral response is a must to end TB

Clarity Sibanda, CNS Correspondent, Zimbabwe
Photo credit: CNS:
A call has been made for governments to act for the prevention of TB-diabetes, a public health challenge that will become more serious unless action is taken now to prevent it in the quest to meet one of the 2015 sustainable development goals which aims to end the TB epidemic by 2030. Paul Jensen, Senior Advisor (Policy) of the International Union Against Tuberculosis and Lung Disease (The Union) said in a webinar organized by Citizen News Service (CNS) that a large proportion of people with diabetes and TB are either not diagnosed, or diagnosed too late.

“It is estimated that 15% of all people with TB worldwide also have diabetes. This comes out to be 1,042,000 adults who have TB and who are also living with diabetes, a number only slightly less than the number of people with TB who are living with the HIV infection”, he informed. For years, the public health community knew that HIV was a major risk factor for TB and that TB –HIV was killing large numbers of people but the tables are slightly turning and the focus is shifting to TB-diabetes co-infection as well.

What causes TB

TB is an infectious disease that usually affects the lungs and is  caused by the bacteria Mycobacterium tuberculosis that most often affects the lungs, although it can also affect other organs such as the bones, stomach, brain, uterus, etc. and the disease can either be active or latent (where no symptoms occur, and the condition cannot be passed on). Latent TB infection carries the bacteria in the body in an inactive state that are not contagious, but they can become active. In active TB, the bacteria do cause symptoms and can be transmitted to others.

About one-third of the world's population is believed to have latent TB. There is a 10% chance of latent TB becoming active TB, but this risk is much higher in people who have compromised immune systems like those living with HIV, the malnourished or those who smoke.

Incessant tobacco smoking has been found to increase the risk of developing active TB with more than 20% of TB cases worldwide attributable to the act. Those  with compromised immune systems, such as people living with HIV, are 26-31 times more likely to develop TB and are also at a higher risk of developing active TB and dying from the disease. This is because smoking and HIV suppresses the immune system, making it harder for the body to fight the TB bacteria.

TB affects all age groups and all parts of the world. However, the disease mostly affects young adults, and people living in developing countries. The good news is that although TB is contagious it is not easy to catch. The chances of catching TB from someone you live or work with are much higher than from a stranger. Most people with active TB who have received appropriate treatment for at least two weeks are no longer contagious.

Since antibiotics began to be used to fight TB, some strains have become resistant to drugs. Multidrug-resistant TB (MDR-TB) arises when the normally used antibiotics fail to kill all of the bacteria, and the surviving bacteria develop resistance to those drugs. MDR-TB is treatable and curable only with the use of very specific anti-TB drugs, which are not only very costly (and hence not affordable by many who need them) but the treatment duration is also 4 times longer as compared to treatment of drug sensitive TB and also accompanied by serious side effects. In 2012, around 450,000 people developed MDR-TB.

TB in Zimbabwe

Zimbabwe, a third world country, is one of the 22 high TB burden countries. Incidences of TB (per 100,000 people) in Zimbabwe was last measured at 552 in 2013, according to the WHO, and these incidences are the estimated number of new pulmonary, smear positive, and extra-pulmonary tuberculosis cases.

Alarming spread of drug-resistant TB threatens global health

Medecins Sans Frontieres/Doctors Without Borders (MSF) has published a briefing paper about the alarming spread of MDR-TB, which they refer to as the "biggest threat to global health you've ever heard of."

Moreover, a new study published in The Lancet has found that patients in South Africa with untreatable TB are being discharged into the community, which, according to researchers, is contributing to the continued spread of the disease.

It is not all gloom

Fortunately, the majority of TB cases can be cured when the right medication is available and administered correctly. But without proper treatment up to two-thirds of people ill with TB will die. People with latent TB may need just one kind of TB antibiotic, whereas people with active TB will require a prescription of multiple drugs, with isoniazid and rifampicin being the two most powerful, first-line (or standard) anti-TB drugs.

TB bacteria can develop a resistance to antibiotics that fail to kill them completely. It is therefore vital that any course of treatment given is fully completed to increase the chance of successful eradication of infection and to reduce the risk of antibiotic resistance developing. TB patients are urged to fully complete any course of treatment, even if the TB symptoms have gone away. Any bacteria that have survived the treatment could become resistant to the medication that has been prescribed, and could lead to developing MDR-TB in the future.

The standard length of time for a course of TB antibiotics is about 6 months in case of drug sensitive TB. All TB medication is toxic to the liver, and although side effects are uncommon, when they do occur, they can be quite serious. Potential side effects should be reported to a health care provider and include dark urine, fever, jaundice, loss of appetite, nausea and vomiting.

A few general infection control measures can be taken to limit the spread of active TB. Wearing a mask, covering the mouth while coughing, and simply having good ventilation in the house can also limit the spread of bacteria. The most important thing to do is to finish entire course of medication when they are prescribed. MDR-TB bacteria are far deadlier than regular TB bacteria. Some cases of MDR-TB require extensive courses of chemotherapy, which can be expensive and cause severe adverse drug reactions in patients.

As Paul Jensen of The Union says, coordinated planning and service delivery across communicable and non-communicable disease is now necessary and must happen at different levels of the health system. A major education programme for care givers and patients must also be implemented so that persons with diabetes understand the risk of TB, recognise the symptoms and present to health care services when they think they might have TB.

Clarity Sibanda, Citizen News Service - CNS
8 August 2015