The scale of the challenge in fight against TB in South Africa

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Southern Africa faces enormous challenges in the fight against TB and TB/HIV coinfection, according to several reports made at the South African TB conference, held in July in Durban.

“What happens in South Africa matters,” Dr Kevin De Cock, head of the HIV Department of WHO said an HIV/AIDS meeting in South Africa 2007. Though he was speaking of HIV, the same can clearly be said for the country’s TB epidemic.

With more than 500,000 cases of TB expected in South Africa this year, the country ranks fourth in the absolute number of TB cases, surpassed only by a few much more populous countries such as India. But with 998 cases per 100,000 people, South Africa ranks second highest in the incidence of TB cases per capita (the highest incidence is in Swaziland, a neighbouring country just a few hours drive away from Durban).

Glossary

extensively drug-resistant TB (XDR-TB)

A form of drug-resistant tuberculosis in which bacteria are resistant to isoniazid and rifampicin, the two most powerful anti-TB drugs, plus any fluoroquinolone and at least one injectable second-line drug. 

multidrug-resistant tuberculosis (MDR-TB)

A specific form of drug-resistant TB, due to bacilli resistant to at least isoniazid and rifampicin, the two most powerful anti-TB drugs. MDR-TB usually occurs when treatment is interrupted, thus allowing organisms in which mutations for drug resistance have occurred to proliferate.

community setting

In the language of healthcare, something that happens in a “community setting” or in “the community” occurs outside of a hospital.

active TB

Active disease caused by Mycobacterium tuberculosis, as evidenced by a confirmatory culture, or, in the absence of culture, suggestive clinical symptoms.

directly observed therapy (DOT)

When a health care professional watches as a person takes each dose of a medication, to verify that all doses are taken as prescribed.

It is well established that the HIV epidemic has driven the explosion of TB in the country. South Africa also ranks second (again, after Swaziland) in the prevalence of TB cases with HIV coinfection and almost 30% of the world’s cases of active TB/HIV coinfection reside in the country. It is believed that 60% of people with TB are also infected with HIV in South Africa.

Worse, one third of 5 million people living with HIV in South Africa have been latently infected with Mycobacterium tuberculosis (M.Tb) and they have a 50% lifetime risk of developing active disease. So the problem of TB cannot be tackled without adequately addressing HIV.

The two epidemics converged about a decade ago — unfortunately, at roughly the same time the country became a democracy. News of South Africa’s HIV/TB health crisis was initially met by the Mbeki administration with suspicion and distrust of the potential partners who were drawing attention to the problem, including people with HIV and their caregivers. The severity of the situation wasn’t fully appreciated, which lead to a delay in mounting effective response to both epidemics.

Social problems inherited from the previous regime compounded the problem.

For example, high unemployment in many communities has forced many in South Africa to be highly mobile, such as the men who must leave their families to go work in the mines, where they live communally and work in poorly ventilated environments that increase the risk of TB. In addition, although the government has been building new homes, it did not keep up with demand from a rapidly growing population. So millions of people are forced to live in overcrowded, poorly ventilated homes in shantytowns.

“In South Africa, 40% of people are actually classified as being poor,” said Professor Anton Stoltz of the University of Pretoria, and the Foundation for Professional Development (which helped organize the conference). “People living in shacks have a high risk for TB because they are living [in cramped conditions] with no airflow systems and they infect each other.”

The high burden of disease, the mobility of population, and the difficulty accessing many of the areas where they reside, strained the TB control system well past its breaking point. While facilities could still diagnose a high number of smear-positive cases and dispense treatment, people with HIV and harder to diagnose TB were often under the system’s radar. Meanwhile, mechanisms to support treatment adherence such as Directly Observed Therapy (DOTS) collapsed without the full complement of trained staff to follow up on patients.

As a result, a high number of people default on TB treatment; and the cure rate is low: below 70% in all the provinces, and below 50% in four, KwaZulu Natal, Mpumalanga, Northwest and the Northern Cape in 2006 (the target is 85%). Consequently, a drug resistance crisis has been emerging. From 2004 and 2007, the total number of MDR- or XDR-TB cases that were diagnosed doubled (to 6000-7000 cases per year); while the number of XDR-TB cases increased 7-fold (to 536 in 2007). But given the fact that many people do not survive long enough to be diagnosed ( especially people with HIV) the actual number of cases is believed to be much higher.

“There was a huge increase in MDR/XDR-TB in the country, but is it perhaps the tip of the iceberg?” said Prof Stoltz. “WHO did a cross-sectional study all over the labs in the world and found that 20% of all TB that they looked at was basically MDR-TB. So If we would say that we have round about 900-1000 people per 100,000 infected, 20% of that comes to about 90 000 people with MDR-TB.”

The surge in the number of new drug-resistant TB cases — and the XDR-TB outbreak — caught the TB programme by surprise. But the hysteria about the “killer TB bug” in the media put tremendous political pressure on the government to do something. The de facto policy reaction has been to try to isolate people with MDR or XDR-TB in TB hospitals — to both prevent them from spreading the infection in the community, and to make certain that they received adequate treatment. But this raises important human rights issues.

“We are going to have legal challenges of the public versus individual rights: what is public health versus the constitutional rights of the patient?” said Dr Stoltz.

Further complicating matters, at present, there are not enough beds in these facilities for all the patients known to have drug-resistant TB — which means that while some are forced to reside in hospitals, others people remain in the community, untreated, and potentially transmitting drug resistant TB for months.

Similar challenges and social context in Lesotho but a different response

Another neighbouring country, Lesotho, faces similar challenges to South Africa but has been taking a very different approach to managing the disease, according to Dr Hind Satti of Partners in Health, who spoke about a couple weeks ago at a Treatment Action Group satellite symposium that preceded the World Lung Health Conference in Paris. Lesotho has an estimated annual incidence for all cases of 691 per 100,000 people, while the HIV prevalence rate was 23.2% in 2005. According to national TB programme figures this year, 80% of TB cases are HIV coinfected.

“The disease has socioeconomic causes and consequences, and we cannot treat it without looking at these social aspects of the disease,” said Dr Satti. In Lesotho, these include poor housing, malnutrition, overcrowding, poverty, and poor infrastructure. “Addressing adherence is key to treatment success, especially those with MDR-TB and HIV disease — without real support to the patient there is no way they can take over 35 pills a day.” But Lesotho has adopted successful community-based models of care for addressing these issues — including providing care to people with MDR-TB in their own homes — rather than trying to house them all in isolation wards in hospitals, unless they are critically ill.

“I think another thing we need to look at is developing context-specific responses,” said Paula Akugizibwe of AIDS and Rights Alliance for Southern Africa in a discussion after Dr Satti’s presentation, “We often develop guidelines and models of care and then bring them to a situation and try to force fit them. What’s been done in Lesotho, this decentralised model of DR-TB care, that’s a realistic approach. We’ve seen so many other places, in South Africa for example, where’s there’s this insistence on treating all DR-TB patients in these facilities — that at this very moment do not have the space to contain all of them — because that’s theoretically the way that it’s felt that it should be done.”