Last month, Doctors Without Borders/Médecins Sans Frontières (MSF) released a special report, their 7th annual list of the "Top Ten Most Underreported Humanitarian Stories". The
list includes the devastating effects of the conflicts in northern Uganda, DR Congo, Colombia, Somalia, Chechnya, on the people living there.
One of the other vastly underreported stories is that tuberculosis (TB) cases are "spiralling out of control" in underdeveloped countries, killing thousands of people per year.
The resurgence of the TB epidemic worldwide has been referred to as a timebomb. There are rising number of cases of multi-drug-resistant TB (MDR-TB), which is fatal if it isn't treated. Treatment is so expensive that it isn't even possible in underdeveloped countries. In places like Africa, the combination of MDR-TB and HIV is indeed a crisis, to put it mildly.
More...
Background
Early history
Tuberculosis is a bacterial respiratory disease caused by Mycobacterium tuberculosis. It is readily spread by water droplets expelled when infected people sneeze, cough, etc.
TB has been around for thousands of years; evidence of TB infections have even been found in Egyptian mummies. It was a major public health problem in 19th and 20th century America and Europe until the antibiotic streptomycin was discovered in 1946.
The return of the epidemic - by the numbers
Between 1985 and 1991, the number of cases in the U.S. alone had increased by 20%. By 1993, the number of TB cases had increased so much worldwide that the World Health Organization declared it a global emergency.
The best way to describe the magnitude of the world TB crisis is to give you some numbers (source):
♦ Someone in the world is newly infected with TB bacilli every second.
♦ One-third of the world's population is infected with TB.
♦ 5-10% of people who are infected with TB bacilli (but who are not infected with HIV) become sick or infectious at some time during their life.
♦ The region of the world with the largest number of TB cases is southeast Asia, at 2.89 million cases.
♦ The region of the world with the highest number of cases per capita is sub-Saharan Africa, at 350 cases per capita.
♦ In 2002, there were 2 million deaths worldwide from TB.
Causes of the current world tuberculosis crisis
As I mentioned previously, the primary causes for the resurgence of the TB pandemic are the rise of multi-drug-resistant (MDR) strains of TB, and HIV infections. Infection with each disease is potentially deadly; concurrent infection is extremely serious and most often fatal.
MDR-TB strains exist because of partial, or inconsistent use, of the most effective anti-TB drugs (isoniazid and rifampicin). In the year 2000, of the 8.7 million new TB cases, 273,000 of these were multi-drug-resistant (source, pdf). The total number of cases worldwide now is probably much higher, since drug-resistant strains are communicable from person to person. It's survival of the fittest, as well as "gene-swapping" between bacteria (don't tell the Republicans!)
As for TB and HIV, the infections essentially fuel each other. Some numbers (source):
♦ One in three HIV-infected people worldwide are co-infected with the TB bacterium.
♦ TB is responsible for the death of one out of every three people with HIV/AIDS worldwide.
♦ People who are HIV-positive and infected with TB are 30 times more likely to develop active TB than people who are HIV-negative.
♦ The TB bacterium enhances HIV replication and might accelerate the natural progression of HIV infection.
♦ Because of the increased spread of HIV in sub-Saharan Africa, the number of TB cases in that region will double to 4 million new cases per year soon after 2005.
♦ Almost half of HIV patients in sub-Saharan Africa develop active TB, whereas only 5% to 10% of individuals infected with TB and not infected with HIV develop active TB.
Doctors Without Borders and the fight against TB
The press release from Doctors Without Borders sums up the problem:
"It's time to openly admit that we'll never be able to 'control TB' by just prescribing more of the same. Massive investment in developing new diagnostic tests and drugs is needed now, so that we can effectively diagnose and treat all those with TB in the shortest possible time," said Dr Francine Matthys, TB advisor to the MSF Campaign for Access to Essential Medicines.
Most TB programs in developing countries rely on sputum microscopy for detection of TB. Developed in 1882, this method only detects the bacilli in about 50% of all people with TB, and its performance is even poorer in children and HIV-positive people. This is alarming, as HIV/AIDS has transformed the face of TB.
Treatment of TB is long and relies on medicines that were invented 40-60 years ago. "In Guinea, and many other developing countries, we regularly see people who have already been treated for TB but return a year or two later with new TB-like symptoms," said Dr Ilse Ramboer, a physician from MSF's TB program in Guinea-Conakry. "These people could be re-infection cases. But they could also be on their way to developing multidrug-resistant TB (MDR TB) - there is no way of telling because most resource-poor settings have no access to drug sensitivity testing." The combination of MDR-TB and HIV/AIDS is a time-bomb waiting to go off in Africa.
Doctors Without Borders are fighting so many new TB cases that the World Health Organization's DOTS approach to tuberculosis control is very difficult to achieve.
So what's the problem? Why not just develop new drugs?
Although the Doctors Without Borders news release gives credit to the Global TB Alliance and Foundation for New Innovative Diagnostics for exploring new diagnostic tests and drugs, sadly, but not surprisingly, the reason is profit:
The drug industry focuses on wealthy markets, not the ones that need them the most, i.e. developing countries. This undoubtedly includes new TB drugs. Moreover, the existing TB drugs that work for MDR-TB can cost tens of thousands of dollars per patient (yes, that's $10,000K minimum per patient). Obviously, this is impossible in, say, Sudan.
Solutions
Some interesting recent research shows promise for a new TB vaccine; the older vaccines aren't active against the new TB strains.
However, the new vaccine is only in the research phases.
Finally, you'd think that the U.S. would be forthcoming with aid to the countries that need it, right?
Think again:
The donor meeting in Paris yesterday on behalf of the Global Fund to Fight Aids, Tuberculosis and Malaria definitely had its surreal aspects. The chairmanship of the Global Fund board is held by Tommy Thompson, the US health secretary, in spite of the fact that President George W. Bush has essentially starved the fund of financial resources. So there was the peculiar spectacle of the health secretary gamely talking up the very fund that his president had been undermining.
The broader context was also bizarre. All speakers agreed that the three pandemics are out of control and that the campaign against them is of unique importance. Eloquent testimonials demonstrated the value of the fund in dozens of impoverished countries. Yet at the end of the day, the rich country governments only inched up their contributions and failed to commit enough to meet the fund's minimum need of $3bn (£1.8bn) for programmes in 2004.
Compare to this. And you wonder why I'm a cynic sometimes.