Walk into an increasing number of quarantined hospital wards in England and the United States and see patients with hacking coughs, fevers, and the look of death. Propped up in beds, these unusual patients are taking drugs to help fight their infection–the age-old disease of tuberculosis. At least for the majority, they are responding to treatment, but some have multi-drug resistant Tuberculosis (MDR-TB). All patients have to stick with six months of treatment, but for the MDR-TB sufferers, the future is less certain.
Every year we mourn the two million who die annually from this disease, and praise the achievements of those who combat this age-old scourge. TB is so bad that along with AIDS and malaria, it has its own special funding arrangement for treatment through the U.N.’s Global Fund. But treatment is becoming less possible because MDR-TB is increasing, and for 400,000 new MDR-TB cases each year there is only one drug that will defeat the disease. Once resistance makes impotent this drug–capreomycin–the millions of MDR-TB patients will be in the same position as those who faced this disease in the 19th century. It is scary and remarkable that Americans could perhaps one day face the same lack of treatment as the tragic literary figure, Camille, who died so painfully from consumption (the old name for TB).
TB is a highly contagious airborne bacterial infection that can spread through the lymph nodes and bloodstream to any organ of the body, but is most commonly found in the lungs. It is very easily transmitted through coughing, sneezing, and just breathing, which is why the World Health Organization (WHO) estimates that each patient transmits the disease to 20 others.
Unlike malaria, which requires numerous mosquitoes, and HIV, which requires sexual transmission or blood transfusion for transmission, TB is easily transmitted through the air. As a result, quarantining TB (and especially MDR-TB) patients becomes important. In Europe and U.S. this is relatively easy because there are significant resources and relatively few cases. But in Africa (and in Eastern Europe, Russia, and elsewhere) resources are absent and caseloads are high, consequently transmission flourishes. Not only does this mean millions of new cases, but it also indirectly helps drug resistance to build.
Treating TB takes a very long time. Failure to complete a course of treatment encourages the development of MDR-TB. Furthermore, if a doctor prescribes the wrong drugs, or does not provide the correct regime for the drugs to be administered, resistance can also develop. Patients who develop MDR-TB can then transmit this new, more dangerous strain to others, just as in “normal” TB.
But the bad news does not stop there. MDR-TB takes an horrifically long 18-24 months of treatment. We have all taken drugs for an infection, and started to feel better after a few days, and wonder why we are bothering with the last few days of treatment. We sometimes don’t finish the course, and it provides a training ground for any surviving bacteria. For the vast majority of us, and on most occasions, this doesn’t matter. But for MDR-TB it can be fatal, not only to the existing patient but to everyone else who might contract it.
Failure to properly treat and contain MDR-TB could result in the creation of a new, even deadlier strain of the disease, which would be resistant to even capreomycin.
Capreomycin is a drug developed and patented by Lilly Pharmaceuticals. Fortunately MDR-TB is susceptible to it, although MDR-TB resists streptomycin, isoniazid, rifampin, and other drugs. Lilly donate large amounts of drugs to the World Health Organization for public-private partnership programs to treat MDR-TB.
Given the extremely long treatment time for MDR-TB, the treatment programs follow Direct Observed Treatment (DOT), where drugs are only administered in a setting where patients cannot forget (intentionally or otherwise) to complete their course of treatment. These programs are currently operating in numerous locations around the world, including South Africa…and keep the number of new MDR-TB cases to under 400,000, when it would be far higher without them.
Given that Lilly cannot make enough capreomycin for the world, it transfers the drug-making technology to small, but competent, drug companies in poor countries. They can then manufacturer the drugs themselves for distribution to WHO programs. Lilly takes no royalty for this production.
The only real long-term hope for tuberculosis sufferers in poor parts of the world is that those countries become wealthy enough to combat the disease in the same way that richer countries do today. Making people healthy enough, through good diet, decent housing, and clean water is the best way for them to fight off TB. But before Africa, Russia, Eastern Europe, and elsewhere embrace capitalistic institutions and become rich, public-private partnerships like the WHO-Lilly one are essential.
There are also lessons for treating AIDS patients from the treatment of MDR-TB. HIV treatment is not a cure, so it lasts indefinitely. The DOT approach adopted for MDR-TB for over 18 months of treatment should be copied for delivery of HIV medicines. Since resistance to HIV drugs is even more prevalent than to TB drugs, this can’t happen soon enough.
For most TB patients the pain is obvious but compared to those with two-year treatment courses, or worse–those without treatment–TB is a painful lottery and for many the result is a death sentence