A long-term probe has found that South Africans with highly drug-resistant TB are "systematically" discharged from hospital without being cured, placing themselves and others at risk, its authors said Friday.
"Treatment failure and discharge of such patients into the wider community is occurring systematically on a country-wide level," said Keertan Dheda, a University of Cape Town professor of pulmonology who led the study.
Experts have long warned that patients with drug-resistant TB who are released without support have a low chance of survival—and may also infect others with the dangerous germ.
But the extent of the problem has not been known, until now.
Reporting in The Lancet, Dheda's team followed 107 people in three provinces who had been hospitalised with extensively drug-resistant (XDR) tuberculosis—meaning they had failed to respond to most or all the main classes of antibiotics.
Forty-four of them were also co-infected with HIV—an extremely dangerous condition that amplifies both diseases.
After four years, 79 of them (74 percent) had died, 32 of whom also had the HIV co-infection.
Seven were still alive and 11 could not be located, the investigation found.
During the study period, 45 of the patients were discharged from hospital.
Just under half of them had failed to respond to treatment and lived less than 20 months on average before they died.
This survival period amounts to a major risk for others in the community, said the study.
In one case, DNA finger-printing of a TB strain confirmed that one XDR-TB patient who had failed treatment and was discharged, transmitted the same germ to his brother, who also died.
"Many patients who fail treatment are being discharged back into the community because little bed space is available in designated tuberculosis hospitals and alternative long-term residential and palliative care facilities are scarce," said Dheda.
He called for the testing of new combined drugs and "tough community infection control plans" to minimise the spread of XDR TB.
Community stay facilities and better home-based care "are urgently needed," he said.
The UN's World Health Organisation (WHO) last year reported that the global incidence of TB is declining, at about two percent a year.
In 2012, 8.6 million people had TB, and 1.3 million died of the disease.
The report warned, though, of little progress in controlling XDR strains and a worrying but slightly less dangerous category called multidrug-resistant (MDR) tuberculosis.
South Africa, along with Swaziland, has the highest rates of prevalence of TB in the world, with nearly 1,000 cases per 100,000 people.
It also has one of the highest rates for diagnosed MDR and the most confirmed cases of XDR TB.
In 2012, about 8,100 cases, 8.5 percent of diagnosed TB cases, were MDR TB, compared with 3.1 percent a decade earlier.
In 2011, about 500 cases were confirmed by lab tests as being XDR, the Lancet report said.
Treating drug-resistant tuberculosis gobbled up almost 45 percent of South Africa's national TB budget, it added.