Tuberculosis Patients Still Waiting for New Diagnostic Tools and Treatment
The number of tuberculosis (TB) cases is increasing worldwide. This is particularly true in countries with high HIV prevalence. There is still no evolution in terms of development of new diagnostic tools and treatment. The only available ones are archaic and do not allow the efficient detection and treatment of TB in developing countries, where 99 percent of deaths occur.
Tuberculosis is one of the three main killer infectious diseases. Each year, nearly 9 million people develop the disease of which about two million die, mainly in developing countries. The worst situation is found in Africa where most of the patients who are HIV positive live.
In this context, diagnostic tools and treatments remain limited and archaic. "To diagnose the disease, we still rely on the microscope examination of sputum, a method developed more than 120 years ago and that only allows the detection of 45-65 percent of cases. This rate is even lower for patients infected by both HIV and TB," says Dr. Marie-Eve Raguenaud, a TB specialist with Doctors Without Borders/Médecins Sans Frontières (MSF). Due to the limitations of the test, the treatment of half the patients in developing countries is often delayed or not started at all.
Also, treatment is long and complex. First-line treatments used today were developed 50 years ago. Patients have to follow a daily treatment for 6 to 8 months which is cumbersome and therefore likely to be interrupted if no support system is in place. At the same time, it is crucial to follow the treatment to completion in order to make sure it is effective and to avoid the development of drug resistance. This may lead to a new episode of sickness or even to death.
To avoid the interruption of treatment, the strategy recommended by the World Health Organization (WHO) requires that patients take their drugs under the direct supervision of medical staff or a trained member of the community. This means that, in most cases, patients have to go to a health center to perform this daily action. This strategy is burdensome for patients and limits access to treatment for TB patients.
Tuberculosis in post-conflicts settings
In some countries characterized by insecurity, absence of road network or simply the collapse of the health system, access to health structures is often very difficult for the population. This is the case in several contexts, mainly in countries with chronic conflict or in a post-conflict situation, where MSF is battling TB.
Angola is a case in point. Thirty years of civil war had left the country in limbo when peace finally came about in 2002. Most people have very limited access to healthcare due to the lack of proximity to a health structure. In 2002, MSF and the directors of Kuito Hospital decided to build an accommodation center for people coming from far away in order to allow them to follow their treatment on the spot to its completion. It is a temporary solution in order to improve access to health care and therefore allow an increase in the number of patients being treated for TB.
Treating people infected both with HIV and TB is also a huge challenge. Today, about 30 percent of the 40 million people living with HIV or AIDS worldwide also have TB. People with HIV or AIDS are more likely to develop TB since their weaker immune system prevents them from fighting off the disease. TB is the most common opportunistic infection and the main cause of death for people living with HIV. Still, the effectiveness of the only existing test for TB is even more limited for HIV positive patients.
Regarding treatment, it is very difficult for TB patients. It gets even worse for patients co-infected with HIV/AIDS. "These patients have to take between 13 and 16 pills a day. Also, there are interactions between AIDS and TB treatment which cause side effects like liver problems or allergies," highlights Dr. Van Cutsem who coordinates one of MSF's programs in South Africa. To address the challenges of TB-HIV coinfection, MSF provides TB treatments in the context of its AIDS programs in several countries: South Africa, China, Cambodia, Kenya, Malawi, and Zambia.
Alternative treatment models developed by MSF
In order to improve treatment adherence in contexts where medical supervision is difficult, MSF has introduced more flexible strategies for patients while keeping high adherence levels. Self-administered treatment models have been launched in Somalia. Pediatric treatments were started in Angola and community and family observation schemes introduced in Cambodia and Mozambique. This allows patients to take their drugs at home and benefit from regular medical follow up.
Other models were also developed by MSF, including some to treat patients who are hard to follow like migrants and nomads. For instance, efforts were made to limit the number of visits patients were requested to pay to the clinic, by introducing home visits in Cambodia or factory visits in Thailand.
Also, in all its programs, MSF is increasingly using fixed-dose combination (FDC) drugs against TB that are easy to use and limit the period of treatment to 6 months (instead of 8). The use of combined drugs also reduces the number of tablets that need to be taken every day, which simplifies the treatment a great deal for the patient. MSF also provides pediatric formulations to its projects in order to improve the way children are treated for TB. Using FDCs also reduces the risk of resistance because patients take all drugs in one pill and are less likely to share pills or stop taking one drug because of side effects.
In addition to these recent developments in MSF's projects to improve TB treatment, MSF is also looking to determine, in collaboration with other experts, how to accelerate the development of diagnostic tests that match the needs of patients and medical staff in developing countries. MSF is committed to supporting the development of new tests by evaluating new technologies on its projects on the ground.
What is Tuberculosis?
Tuberculosis is an infectious disease caused by a bacteria, myco-bacterium tuberculosis, that could, according to the World Health Organization (WHO), infect one third of the world population.
Between 5 and 10 percent of infected people develop the disease and become contagious at some point in their lives.
Tuberculosis usually develops in the lungs, the main zone of infection. Major symptoms are: prolonged cough, bloody expectorations, chest pain, and changes in a person's general health status. Coughing, sneezing, talking, and spitting can all spread the bacilli in the air where they can remain for several hours before being inhaled by another person.
People with compromised immune systems are more susceptible to the disease. This is why people living with HIV/AIDS are more likely to develop the disease if infected.
In the last few decades, the number of multi-drug resistant TB cases has been on the increase. Interruption of treatment is usually the cause for the disease becoming resistant to one or more drugs.
MSF and Tuberculosis Treatment
Since its first day of operation, more than 30 years ago, MSF has been active in the field of TB. In recent years, MSF has been increasing the number of TB patients in many projects by refocusing its action from the control of the disease to the care provided to patients.
In 2005, MSF treated patients in 50 projects spread over 27 countries: Angola; Abkhazia (Georgia); Armenia; Burundi; Cambodia; Congo-Brazzaville; Côte d'Ivoire; China; Ethiopia; Guatemala; Guinea; Indonesia; Kenya; Liberia; Malawi; Myanmar; Nepal; Niger; Nigeria; Russia (Chechnya); Democratic Republic of Congo; Somalia; Sudan; Thailand; Uganda; Uzbekistan; Zambia. About 15,100 new TB patients were admitted in MSF programs in 2005, and even more were diagnosed by MSF teams and referred to local health services for treatment, some of which are supported by MSF.
Contexts in which MSF provides treatment vary considerably. In some cases, treatment takes places in chronic conflict situations as in Somalia and southern Sudan, or post-conflict settings like Angola. Also, a number of patients receive TB treatment in health centers supported by MSF, such as in southern Sudan, the Democratic Republic of Congo, and Angola, or even as part of our interventions in prisons. MSF indeed provides treatment in penitentiary institutions in Abkhazia and in Abidjan, Ivory Coast.
Finally, MSF treats multi-drug resistant TB in Ivory Coast, Abkhazia, Thailand, and Uzbekistan.