Tuberculosis kills more people each year than any other infectious disease—1.6 million deaths worldwide in 2017.
An alarming rise in drug resistance, reliance on harsh drugs that often don't work, and a lack of diagnostic tests practical to use in low-resource settings all help fuel the global tuberculosis (TB) crisis. MSF is a major non-governmental provider of TB care worldwide, especially for drug-resistant TB, and helps lead the global push to make newer, more effective treatments affordable and available to those who need them.
What causes TB?
TB is caused by bacteria that spread through the air when infected people cough or sneeze. It typically affects the lungs but can infect other parts of the body, including the bones and nervous system.
Most people who are exposed to TB never develop symptoms, although they can still harbor the infection in an inactive form. But if the immune system weakens, latent TB bacteria may become active and cause disease. About 10% of people with latent TB go on to develop active TB and become contagious at some point in their lives.
Who is most at risk?
The global TB crisis has grown dramatically since HIV became a widespread epidemic. That’s because people living with HIV/AIDS have weakened immune systems, which increases their risk of contracting and dying from TB—now the leading cause of death among people with HIV. People with other medical conditions that weaken immunity are also at a higher risk of TB infection and death. So are children, the elderly, people from regions with high TB rates, and those living in close quarters like prisons, refugee camps, and crowded slums.
What are the symptoms of TB?
Symptoms are most often a prolonged cough and fevers, but TB can also affect many other organs. Prolonged fevers, night sweats, and weight loss are all common.
How is TB prevented?
Early and effective treatment for people with active infection lessens the chance they will pass it on to others. Masks worn by health workers, caretakers, and those infected with TB can help avoid catching or spreading the disease. A highly effective vaccine is not yet available but is urgently needed to replace the current, poorly effective one developed a century ago.
How is TB diagnosed?
Worldwide, the majority of people infected with TB have not been diagnosed because tests are not available where they live or are not a routine part of primary care. Changing this will require developing better, cheaper and easier-to-use tests.
Until recently, the most common methods to diagnose TB were to examine patient sputum samples (phlem coughed up from lungs) under a microscope or by bacterial culture. Both need a laboratory and a trained technician, making them ill-suited for many low-resource settings. And neither test is reliable in children, people with HIV, people with TB outside the lungs, or those with drug-resistant TB. In the case of culture, it can take as long as 8 weeks to get a result, which delays patients in starting treatment.
In 2010 a much faster, more accurate diagnostic test called GenXpert MTB/RIF was introduced and is now used for many patients, and to identify drug-resistant TB. It's a big improvement but still requires a laboratory with stable electric power, trained technicians, and other supplies and infrastructure, and it still misses TB infections in certain groups of patients. So better diagnostic tools remain an urgent need.
How is TB treated?
Uncomplicated, drug-sensitive TB is curable, but treatment takes a minimum of six months and relies on a cocktail of the same antibiotics that have been used for decades.
People with multi-drug resistant TB (MDR-TB) cannot be cured by the two most powerful 'first-line' antibiotics. Instead, they usually face at least nine months of treatment, and sometimes as much as two years. During this time they must swallow over 10,000 pills and endure 6-8 months of painful daily drug injections, often with severe side effects such as nausea, joint pain, psychosis or hearing loss. These drugs are not adapted for children, and they are more challenging to use in TB patients who also have HIV.
More effective, less harsh treatments for MDR-TB, including its most severe form (extremely drug-resistant TB, or XDR-TB), have recently been developed and offer hope for saving many more lives.They rely on two drugs, bedaquiline and delamanid—the first new TB medicines in 50 years. But access to these new drugs is extremely limited: in 2017 they reached fewer than 5% of patients who need them, and they are not yet available in many countries with the highest TB burden.
How MSF responds
We have been involved in TB care for over three decades, often working alongside national health authorities to diagnose and treat patients in a wide variety of settings--from chronic conflict zones and refugee camps to urban slums, prisons, and remote areas. In 2017 we provided care for TB patients in more than 24 countries, often focused on drug-resistant TB.
Our programs aim to provide as many TB services as possible in outpatient community settings rather than by hospitalizing patients, which has long been the practice. In some cases, we conduct our own clinical studies (or partner with others) to develop the best combinations of new and old drugs, including shorter, all-oral regimens.
We also advocate for rapidly expanding access to these new treatment options, intensifying research and development of new TB diagnostics and medicines, and lowering the cost of treatment.
With the EndTB and PRACTECAL clinical studies, MSF and its research partners aim to develop shorter, more effective, and less toxic MDR-TB treatment regimens that include one or both of the new drugs.
Read how an MSF TB doctor describes the game-changing shift from older to new drugs:
"Combatting MDR-TB: Bringing a Knife to a Gunfight"