IPN Opinion article
by Lorraine Mooney
Most of us probably think of tuberculosis as a disease of the past - something that killed off our weaker ancestors and was eliminated by antibiotics. It may come as something of a shock, then, to learn that each year approximately 8 million people are infected with TB and 2 million die. TB is the second leading cause of death in Africa after Malaria, and some 2 million people are infected with the disease annually. What is perhaps most galling is that these deaths are preventable. But priorities for treatment are warped towards higher-profile diseases such as AIDS.
The failure to treat TB appropriately means that infection rates are rising at 2 per cent a year and resistance to drug therapies is increasing. And it is spreading - resistant strains are spreading at alarming rates in Eastern Europe and have occasionally hit London and New York.
The Mycobacterium tuberculosis bacillus lies dormant in a third of the world's population. In that state it is usually benign, but can be reactivated if the host's immune system is compromised. Once a person becomes tuberculous, they produce 4 billion or so bacilli each day. These can survive freezing, drying and putrefaction and will blow about as dust for months - plenty of time to find a new host.
The good news is that treatments for TB exist. The most advanced of these, bactericidal drugs developed in the fifties and sixties (and now off-patent), have a 98% chance of success - if used appropriately. But TB will develop resistance to any drug used on its own, often after only two to three days. For success, at least four drugs must be used in combination for two months, followed by four months on two drugs.
The bad news is that failure to complete this onerous regimen - which means taking ten or more pills regularly, every day - will almost certainly lead to multi-drug resistant TB (MDR-TB). Given that a patient is no longer infectious after two weeks and begins to feel better, there are cases where the patient stops taking their medicine, or worse, sells it. This is disastrous because mortality rates for MDR-TB run as high as 80%.
To combat this, the World Health Organisation developed a tuberculosis control strategy known as DOTS (Direct Observations of Treatment Short-course). DOTS involves: diagnosis by a laboratory, regular supplies of drugs, strengthened programme supervision, and the use of standard drug treatment with at least the initial treatment being directly observed by a trained treatment supporter.
One reason for the rise in incidence of TB is the explosion in HIV/AIDS. HIV weakens the immune system, providing ideal conditions for TB to thrive. Indeed, a third of HIV patients actually die of TB. As a result, the WHO recommends that patients with TB have routine HIV monitoring in addition to liver function tests, a sputum test and a chest x-ray, both at the beginning and end of TB therapy. But these tests are expensive and require equipment that poor rural clinics simply do not have. Even rich countries are having trouble.
In the late 1990s there were two hospital-based mini-epidemics of MDR-TB in London, and another in the early 1990s in New York City. The estimated cost of treating each patient in that outbreak was $250,000 and the City spent nearly $1billion before it was contained. An audit of 43 high incidence TB districts carried out in England and Wales in 2001 found 86 per cent had insufficient staff to treat patients with TB, while notifications of TB had increased by nearly 20 per cent since 1991.
The situation in poorer countries is considerably worse. Abject poverty means many patients cannot afford to travel to a clinic. Those that have the means to travel often find that when they arrive at the clinic, there are no doctors, no diagnostics and no drugs. In countries where adequate supplies of the drugs are not readily available, the prevalence of MDR-TB is as high as 50%.
Thankfully, drugs are - in principle - available to treat MDR-TB and there are some rays of hope. For instance, five years ago, Eli Lilly initiated a philanthropic programme with the WHO and MÈdecins Sans FrontiËres, to distribute capreomycin and cycloserine at a fraction of production cost.
The WHO has developed a ëDOTS-Plus' programme to treat MDR-TB. But this programme is complex and expensive and it is recommended that it should only be undertaken at recognised centres with experience of managing such patients. DOTS-Plus takes two years and has been estimated to cost 1400 times as much as the standard treatment. However, another public-private partnership - the Global Alliance for TB Drug Development - is developing new drugs that will hopefully reduce the treatment time and cost.
In spite of the high cost of treating MDR-TB, a recent study by Results Educational Fund and the Open Society Institute suggests that a mere $253 million would be sufficient to treat all the TB patients in the most impoverished nations. Sadly, though, it seems unlikely that enough funds will be spent on TB even to make much of a dent in the numbers. This is in spite of the fact that governments around the world have committed billions of dollars to programmes intended to combat the diseases of poverty. The reason for the shortfall in treating TB is that the administrators of the funds are prioritising other diseases, especially AIDS, because they have a higher political profile.
The World Health Organisation has announced that today is World TB Day. If the WHO and other bodies responsible for dispersing funds to deal with diseases would focus on TB every day instead of only on 24 March, maybe we could cure the world of this deadly disease.
Author: Lorraine Mooney is a medical demographer and a Research Fellow with International Policy Network.
This article may be republished without prior consent but with acknowledgement to the author. The views expressed in the article are the author's and are not necessarily shared by the members of the Free Market Foundation.