Outbreak in South Africa regarded as major setback in fight against spread of TB The WHO has warned of a possible TB endemic in the developing world, writes Joe Humphreysin Johannesburg
Efforts to combat the spread of tuberculosis globally have received a major setback with confirmation of an outbreak of a drug-resistant strain of the disease in South Africa.
South African researchers first identified extreme drug-resistant TB (XDR-TB) in the local population six months ago.
Now, they estimate there are at least 600 cases of infection in the country, with a fatality rate of 84 per cent.
The World Health Organisation (WHO) has called for an urgent international response, warning of a possible epidemic of XDR-TB in the developing world, especially among populations already weakened by HIV/Aids.
XDR-TB, and the more common multidrug-resistant TB (MDR-TB), tend to emerge in locations with poorly managed tuberculosis treatment programmes.
Wealthy nations are not immune from infection, however, with the WHO recording cases of the disease in 28 territories, including the United States.
Ireland recorded its first case of XDR-TB in 2005 - the latest year for which statistics have been compiled by the Health Protection Surveillance Centre (HPSC).
A further two cases of MDR-TB were recorded in Ireland in 2005.
In South Africa, the outbreak - which began in rural KwaZulu-Natal - has prompted a degree of panic.
Earlier this month, a number of patients demanded to be discharged from East London's Fort Grey Hospital after cases of XDR-TB were transferred to the institution. A hospital spokesman said some patients "went on the rampage", trying to flee the institution as quickly as possible, until finally calm prevailed.
In a related incident, patients suffering from MDR-TB complained last month that they had been "imprisoned" in a Johannesburg hospital, and were being "treated like criminals" by the authorities.
The South African Medical Research Council (SAMRC) has warned the government against taking a heavy-handed approach to the crisis, saying public welfare must be balanced against individual rights.
In a statement, the council noted there was a "real risk" XDR-TB would be driven underground, "especially if isolation measures are coercive. This is a situation [South Africa] can ill afford."
To date, most cases of MDR-TB have been recorded in countries of the former Soviet Union, and in Asia.
The WHO estimated in 2004 that more than 400,000 people could not be treated with at least two key first-line tuberculosis drugs. Most cases were in China, India and Russia.
A particularly worrying finding in South Africa is that more than 80 per cent of those infected with XDR-TB are HIV/Aids patients.
The correlation extends from the fact that HIV/Aids sufferers have - for various reasons - more difficulty consuming an even supply of TB drugs. It is in this environment, where tuberculosis treatment courses have been either interrupted or prematurely stopped, that drug-resistant forms of the disease tend to emerge.
Mario Raviglione, director of the WHO's Stop TB Department, said this week that if the trends continued there could be a "practically uncontrollable" epidemic of XDR-TB among HIV/Aids sufferers in the developing world.
He said it was possible the strain had already spread to other countries in Sub-Saharan Africa where monitoring was less effective.
"If all the elements of good TB control are put in place, we have a chance of taking care of this disease," he said. "If we let the situation . . . with XDR go out of control, as it might well do, then we are in trouble. All of our gains over the last 10 years in controlling TB would be lost."
HIV/Aids patients often have difficulty sticking rigidly to TB treatment courses because of problems with diarrhoea and other Aids-related ailments. Additional factors in Africa that can hamper the supply of TB medication are poverty and weak public health management.
South Africa's department of health has announced plans to improve the training of nurses and doctors to deal with the crisis. It has also rushed through the licensing of a number of second-line medications for the treatment of drug-resistant TB.
The drugs have been found to produce side effects including deafness and mental illness. However, these can be controlled by properly trained physicians, according to Dr Patrizia Carlevaro of the multinational drugs firm Lilly, which produces some of the medications.
Speaking on a visit to Johannesburg, she said Latvia, and some other countries in the former Soviet Union, had done "pretty well" in managing XDR-TB by using the drugs, along with other interventions. She stressed, however, "You don't just send the drugs without any training. That would be very dangerous."
Tuberculosis, an airborne disease spread like the common cold, afflicts about nine million people each year and kills 1.6 million, according to the WHO.
There were 461 cases of TB in Ireland in 2005, according to the HPSC which has said that drug-resistant TB "needs to be kept under close surveillance".
The State body referred to the issue in a recent report on the epidemiology of tuberculosis in Ireland.
"It is of critical importance to TB control in Ireland that surveillance of TB and reporting of outcome data be maintained at a high level in view of the increased incidence of TB, in particular multidrug-resistant forms, worldwide," the HPSC said.