Multi-drug resistant (MDR) TB has more than doubled in the past three years at Durban’s busiest TB treatment clinic, the Prince Cyril Zulu Communicable Diseases Centre in Warwick Triangle, which oversees the treatment of 5 000 TB patients every month.

This confirms the findings of a report released by the World Health Organisation last week (16 March) that singled out South Africa as one of 10 worldwide hot spots for MDR TB.

TB and HIV/AIDS expert Professor Salim Abdool Karim says that the increase in MDR TB is “a warning bell to take action”.

“But that action is not complicated,” adds Abdool Karim, who is the University of KwaZulu-Natal’s deputy vice-chancellor for research.

“MDR TB is avoidable, provided that people complete their treatment. It occurs when people don’t take the full course or take it intermittently. The TB organism is then exposed to the drugs at levels that don’t kill it and it adapts, thus becoming drug resistant,” he explains.

Abdool Karim says that, at present, MDR TB is mostly found in people who have defaulted on TB treatment and have thus acquired resistance.

TB is an airborne disease, and the bacteria are usually spread when an infected person coughs, spits or sneezes. MDR TB is spread in exactly the same way, and does not just affect those who have failed to complete their six-month TB treatment. Anyone exposed to a person with MDR TB can get the resistant strain even if they have never had TB before.

“As the numbers of patients who have defaulted and become drug resistant increase, this will pose a great problem because these people then become sources of community-acquired MDR TB,” warns Abdool Karim.

According to Prince Cyril Zulu’s nursing manager, Jeanne Liebetrau, around 1.3% of those who have never had TB before are infected with MDR TB, while 7.3% of those treated for recurrent TB show some resistance to the standard TB drugs.

Meanwhile, cases of ordinary pulmonary (lung) TB have increased fivefold in the past 10 years at the centre, jumping from 807 cases in 1992 to 4 077 in 2002. About 5 200 new TB patients were treated last year.

Millions of South Africans have been exposed to TB bacteria, but the disease only generally develops in people with weak immune systems. The massive increase in TB is in part due to the HIV epidemic, as well as malnutrition, stress, diabetes and other conditions that affect immunity.

KwaZulu-Natal has one of the worst TB cure rates in the country, with less than half of new cases being cured. However, Abdool Karim says it is difficult to get accurate statistics as “patients come for treatment, then disappear so we have no idea whether they are cured or not”.

In a bid to improve the cure rate, the Prince Cyril Zulu Centre employs 18 fieldworkers who try to link TB patients to a local directly observed treatment short-course (DOTS) programme, where responsible community members or clinic staff oversee their daily treatment.

“At the centre, patients are asked where it would be most convenient for them to collect their medicine,” says Dr Ayo Olowolagba, who heads both the centre and the city’s communicable diseases section.

“Our infection controllers, who each have a car and are responsible for different areas of Durban, then deliver the medication to the patient’s local clinic, DOTS supporter, or to their employer,” he explains.

But there are still problems with this system, as patients from outside the metro often give false addresses in order to be treated at the centre and then fail to pick up their medication.

Ordinary TB treatment is based on two drugs, Isoniazid and Rifampicin. It lasts for six months and costs around R400. MDR TB, which usually requires lengthy hospitalisation and a variety of different drugs for at least 18 months, can cost R20 000.

A profile of defaulters drawn up by centre staff in 2001 shows that the vast majority (73%) lived in informal settlements, and over half (55%) stopped treatment after only four weeks.

“Most people default in the first two months of treatment, when they start to feel well,” says Liebetrau.

“The best cure rates happen in communities like Lamontville, where the local health committees are strong and DOTS is going well,” she adds.

Many of the centre’s patients are also infected with HIV. For this reason, the Centre for the AIDS Programme of Research in SA (Caprisa) is involved in research to see whether patients will be able to tolerate antiretroviral drugs at the same time as TB treatment.

“We are trying to understand whether we can give patients four TB drugs and three antiretroviral drugs at the same time,” says Abdool Karim, who is also a director of Caprisa.

“Research has shown that mortality in people infected with TB and HIV peaks after three months of TB treatment and again at around seven to eight months. So we are trying to understand whether we can save lives by treating people at the same time,” he says.

At present, it is usual practice for people to complete their TB treatment before going onto ARVs.

 E-mail Kerry Cullinan