Tuberculosis: The Issues
Tuberculosis – The curable disease that continues to kill
TB in Children
The Need for New TB Tools
TB in Children
The Need for New TB Tools
With 9.4 million new cases and 1.7 million deaths each year, tuberculosis (TB) is one of the developing world’s biggest killers; 85 percent of cases occur in Asia and Africa with Eastern Europe also affected. In recent years there has been a dramatic resurgence of the disease in people also infected with HIV. In addition, drug-resistant strains of the disease are on the rise. Controlling the spread of TB is severely hampered by the fact that the disease is very difficult to both diagnose and treat, with research and development into new tools to tackle the disease severely lacking.
The most widely-used test for diagnosing active TB in developing countries relies on examining a patient’s phlegm under a microscope. This method, developed nearly 140 years ago, detects less than half of all active TB cases and in particular largely fails to detect the disease in children, people co-infected with HIV and those with drug-resistant forms of TB. Other diagnostic methods exist but these require laboratories, a steady power supply and skilled staff to deliver results which are mainly unavailable in remote and rural settings. A new test that has recently come to market takes us a big step in the right direction, providing more accurate and rapid results, but is still expensive and not simple enough to use in the most resource-limited settings. Efforts to develop an affordable rapid test that delivers results on the spot need to be ramped up.
TB is curable, but treatment takes a minimum of six months on a cocktail of various antibiotics – the treatment regimen has remained essentially unchanged for decades, with no improvements being developed. Treating drug-resistant TB, which does not respond to the main drugs used for TB, requires people to endure an arduous treatment course of up to twenty pills a day, and in the early stages of treatment, a daily painful injection. The side effects of such treatment are severe. In addition, some of the drugs are very expensive and beset by supply problems that have led to dangerous shortages.
Tuberculosis (TB) is the number one killer of people living with HIV/AIDS; due to weakened immune systems, they are much more likely to develop the disease. Unfortunately, diagnosing TB in people with HIV is difficult and the lack of effective diagnostic tools means many people go undiagnosed. Drug-resistant forms of TB (DR-TB) are even more difficult to diagnose and treat. The drugs to treat DR-TB can have intolerable side effects that make it difficult for patients to continue taking them, and some TB drugs can also interact with HIV medicines and so cannot be taken at the same time. Integrating HIV and TB care is critical to lessening the burden on people infected with both HIV and TB, and ensuring they stay on treatment.
TB is one of the top ten causes of death in children, with a global estimate of 130,000 deaths per year. As TB is a disease of poverty, by far the largest numbers of children affected live in low-income countries. The disease is difficult to diagnose and treat in children, and research into new medical tests and medicines that could improve the situation has been severely neglected; the most widely-used test for diagnosing TB in poor countries largely misses cases in children. Most of the TB medicines have not been tested for safety and efficacy in children and none of the current drugs for drug-resistant TB come in child-friendly formulations.
After decades of neglect, there has been a recent upswing of activity in the development of new drugs and diagnostic tests to treat TB. Several new drugs are now expected to come out of the drugs pipeline in the next couple of years, although this is still not sufficient to tackle the dramatic resurgence of the disease. A new molecular TB test is currently being rolled out that could diagnose many more patients, particularly those co-infected with HIV. However, we are still lacking a simpler rapid, accurate and affordable TB test that can deliver results on the spot and is easy-to-use in resource-limited settings.