Bonus Post: The TB Edition
Cindy here. Sometimes I feel rather out-of-my-element here in Peru, since I don’t speak Spanish and Lauren+Briana have to constantly translate for me. They’re doing a great job of it, and apparently they enjoy my unending stream of questions, as it takes the pressure off them to think of questions and allows them to focus on translating. We have a good triumvirate going on. Still, there are many times where I feel useless and awkward (hopeful GROW-trippers who do not speak Spanish, take heed), so as a side project, I started researching TB as a worldwide problem and the equally global response to it. Tammy and the ghU team has covered some of these facts during a General Meeting, but I decided to include everything here for comprehensiveness.
Some basic TB facts and statistics.
TB is an infectious airborne disease caused by Mycobacterium tuberculosis. It is spread when a person with active TB coughs, sneezes or otherwise transmits their saliva through the air. TB infections are usually latent but can become active TB disease, where the bacteria eats away at your lung tissue or harms other parts of the body (such as the spine, brain, etc).
There are around 9 million new cases of TB each year and close to 2 million deaths. In fact, 1/3 of the entire world’s population is infected with latent TB, and most of these people are unaware of their infected status.
There is also extensive co-infection with HIV/AIDS: over 10% of TB patients are also infected with HIV, and TB is responsible for 1 in 4 deaths among HIV-positive patients. This is because TB is an opportunistic infection that transitions to active disease most easily in immunocompromised patients.
Millennium Development Goal: to halve the incidence of TB by 2015.
There are two additional goals developed by the Stop TB Partnership: to halve TB prevalence and death rates by 2015, and to eliminate TB by 2050 (defined as less than 1 case of TB per 1 million population per year).
Let me take a break here to say something about these statistics. They look nice and definite and are backed up by the World Health Organization (WHO), but I wouldn’t trust them to the letter: they are best estimates rather than verified facts about the state of the world. Peru, and probably many other countries, do not have the personnel to comb the population for active or latent TB cases. They wait for the patients to come to them. Because of stigma or lack of access to healthcare, many patients do not show up at the health clinics to be checked out. Furthermore, the governments of these countries may not receive accurate statistics from the clinics due to bureaucratic inefficiency, or the governments may have incentive to misrepresent the statistics in order to diminish the appearance of poverty. The WHO simply compiles these statistics from various national governments; it does not have the resources to verify them.
So on a fundamental level, we do not know the scope of the epidemic – and that lack of information is both consequence and cause of the problem of TB. Even more scary, despite our lack of a clear, comprehensive picture, TB is still a major public health concern.
Global Plan to Stop TB
The Stop TB Partnership addresses this state of things in its Global Plan, which has two focuses: 1) Implementation of existing diagnostics/interventions and 2) Research and Development.
The Implementation part of the Plan has 4 objectives, which I divide up into the areas of Infrastructure-strengthening and Targeting at-risk sub-populations. These 4 objectives are:
1. Directly Observed Treatments (DOTS) expansion and enhancement
2. Drug-resistant TB
4. Laboratory Strengthening (referring to laboratory diagnosis of TB rather than R&D)
A lot of infrastructure needs to be constructed/strengthened: health clinics, hospitals and diagnostic labs need medicine, equipment and staff.
Two specific sub-populations are targeted: patients with drug-resistant TB (MDR-TB or XDR-TB) and patients co-infected with TB and HIV.
A short detour into the details of drug resistance.
MDR-TB refers to bacterial strains which are resistant to Isoniazid and Rifampicin, the two most important first-line drugs.
XDR-TB is MDR-TB that is resistant to additional drugs (a fluoroquinolone and at least one second-line injectable drug).
The current treatment regimen for regular TB takes 6 months. The current treatment regimen for MDR/XDR-TB takes up to 2 years, is less effective, more toxic and more costly (~$2000-5000 per patient, usually shouldered by the state).
The WHO estimates that around 0.5 million cases of MDR-TB occur each year and up to 150,000 deaths.
The Research & Development part of the Plan has 5 objectives, which basically boil down to we need to know more about this disease, biologically and epidemiologically, and we need to know more about the effectiveness of treatments, social projects and policy. These 5 objectives are:
1. Fundamental research (which will lead to the other 4 objectives…)
2. New diagnostics
3. New drugs
4. New vaccines
5. Operational research (i.e. are things working and how can we make them better)
I’m a big fan of biomedical research. Even though TB is curable, I think we need faster and more accurate diagnostic tests to detect both active and latent forms of the bacteria. We need more therapeutics against drug-resistant bacteria. A(n effective) vaccine against adult TB would revolutionize public health. I know that biomedical research won’t solve everything: there are still the problems of patient compliance and social stigma, which is why infrastructure-building and social programs are crucial to public health. There’s still the overwhelming poverty that inflicts a very large portion of the globe. But I believe that effective diagnostics and treatments (and, hopefully, a vaccine) will go a long way in preventing unnecessary deaths throughout the world. I believe that they will stop the impoverished from being so severely disadvantaged and disrupt the poverty-illness cycle, so that those who are motivated will have the opportunity to work hard and chase their dreams. That’s why I’m glad that the Stop TB Partnership has made R&D an important focus of their Global Plan.
The Global Plan was originally written in 2006, but these objectives are from the 2011 update to the Plan. The update also estimates that the Plan will require $47 billion over 5 years to successfully fund all aspects and objectives, $37 billion for Implementation and $10 billion for R&D. Melecio says that the Partnership is having trouble gathering funds (probably due to the economic slump) and may not meet its goals for 2015. It’s still a pretty good plan for what needs to be done on a global scale to combat the problem of TB, which is why I felt it was valuable to do a post about it.
I don’t know how many of you have made it to the end of this post – I realize it’s pretty text-heavy. But hopefully you’ve learned something, and definitely comment or email if you have any questions! I’ve just learned most of this in the past 2 weeks, so I don’t know if I’m explaining it very well.
Here is a photo of a child so we can all smile and remember what we’re working for, in the end: the potential of the future. 🙂