It is a medical paradox that has public-health workers very worried. Powerful drugs meant to cure people of tuberculosis are indirectly killing them instead.
And the World Health Organization (WHO) is raising the alarm.
Second-Line Drugs
For years, doctors have been battling multi-drug resistant cases of tuberculosis using ever-stronger pharmaceuticals called second-line drugs.
But if those strong pharmaceuticals are not used as prescribed, they can give rise to a new strain of extreme drug-resistant tuberculosis.
And that has no cure.
In Eastern Europe and the former Soviet Union, where there has been a resurgence of tuberculosis, cases of the extreme drug-resistant variant are rising fast.
"The treatment of TB, in general, has to follow some fundamental principles," says Ernesto Jaramillo, a WHO medical officer at the Johannesburg conference. "First of all, the treatment regimen has to be properly designed and should consist of a cocktail with the right drugs, that should be delivered in the right way. If medical doctors prescribe the wrong drugs, and or if the patient does not take the drugs properly, then the obvious consequence is that -- over time -- drug resistance develops."
A recent outbreak in South Africa of what scientists call extreme drug-resistant tuberculosis, or XDR-TB, killed 52 out of 53 patients infected.
Eastern Europe, Former Soviet Union
In Eastern Europe and the former Soviet Union, where there has been a resurgence of tuberculosis, cases of the extreme drug-resistant variant are rising fast.
Latvia is one example. According to the World Health Organization, it has one of the highest rates. Every fifth case of multi-drug resistant tuberculosis in the country has already morphed into the extreme drug-resistant type.
Russia, Ukraine, and the Central Asian countries, where tuberculosis cases among prisoners have reached epidemic proportions, could soon face the same problem.
This is largely due to a breakdown of the health services in the post-Communist era.
Complex Treatment
Patients who suffer from multi-drug resistant tuberculosis have to take a cocktail of medicines for a long period of time. That is expensive and requires close doctor supervision.
If treatments are skipped or medicines are taken out of sequence, the disease is not cured and can metamorphose into the extreme drug-resistant variety.
Jaramillo says the meeting in Johannesburg will start working on guidelines for health-care workers worldwide, to stop the rise of extreme drug resistant tuberculosis.
Prisoners in Nizhny Novgorod, Russia, being screened for tuberculosis (TASS)
“What we are going to do is to set up a task force that will be reviewing the current situation and making precise recommendations by the end of the year about how to tackle [extreme drug-resistant TB]," he says. "But in the meantime, what we are strongly recommending is to ensure that second-line drugs -- the drugs used to treat [multi-drug resistant] TB -- are properly used. The rational use of second-line drugs is the most powerful way to prevent the creation of extreme drug-resistant TB."
Working With Drug Companies
The WHO is also trying to persuade pharmaceutical companies to offer discounted drugs to countries in need, to avoid an epidemic of extreme drug-resistant tuberculosis, before it is too late.
"There has been important progress in recent years," Jaramillo says. "One major pharmaceutical company has embarked on transferring technology for producing two key drugs. However, the treatment regimens for multi-drug resistant TB consist of at least four drugs. So although there is progress it is still not enough for what we need."
In one piece of good news earlier this year, U.S. tycoon Bill Gates announced a gift of $600 million to fund antituberculosis programs around the world.