While global death rates from some of the biggest infectious disease killers have dropped markedly in recent years, mortality rates from TB have been the same, with 1.5 to 2 million people dying each year from the curable disease. According to Salman Keshavjee, of Harvard Medical School, we need to change the paradigm when it comes to TB control to see the same results we’ve seen from global HIV/AIDS and malaria responses.
His views on how to achieve zero deaths from TB are summarized in the Institute of Medicine’s recent report on the global crisis of drug-resistant TB, itself a summary of a joint workshop hosted by the IOM and the Institute of Microbiology of the Chinese Academy of Sciences in Beijing earlier this year. At the workshop, participants discussed the opportunities for emerging leadership in drug-resistant TB control from the BRICS countries – Brazil, Russia, India, China, and South Africa – and discussed innovative strategies to advance efforts to address drug-resistant TB.
“Overall, we have not been successful with the tools that we have been using,” Keshavjee said. Optimal biomedical approaches and delivery systems haven’t been used to attack the disease, he said in his presentation, and one of those approaches is the Directly Observed Treatment-Short course (DOTS) system. Calling the DOTS system a minimalist, not an optimized strategy, he pointed out that it was never designed to address drug resistance. “Years of advocating an approach that overlooked resistant strains was a mistake,” he said.
While DOTS requires having a regular supply of high-quality drugs, which has had great benefits, the program also has several limitations, including a lack of integration with country procurement systems, a lack of second-line drugs or drugs for adverse events, a reliance on patients presenting themselves when sick rather than active case detection, and no strategy for addressing latent TB disease. With a focus on short-course therapy, DOTS has curtailed the development of appropriate adjunct therapies, such as surgery for patients with advanced disease.
The minimalist approach has resulted in a lack of focus on transmission and infection control, which has contributed to the spread of the disease. It has also led to limited engagement with the private sector. “The paradigm we have been working within has been very inflexible,” he said.
Keshavjee urged moving from a minimalist approach to an “optimalist approach,” with includes employing the FAST strategy, introduced earlier at the Beijing workshop. FAST stands for:
- Find TB cases through rapid diagnosis
- Perform Active case finding by focusing on cough surveillance
- Separate safely and reduce exposure through infection control
- Treat effectively based on rapid drug susceptibility testing
With one-third of all TB cases going undetected each year, developing a true point-of-care test for TB and drug resistant TB is key for rapid case detection in resource limited settings, he said. He added that although HIV and TB have been driving each other’s epidemics for years, the percentage of people infected with HIV screened for TB remains low. “On a global level, every person with HIV should be screened,” he said. He also pointed out that more appropriate diagnostics and case-finding strategies for children remain “a dire need.”
Universal access to care may be extremely difficult to achieve, he said, but it must be a priority, because when patients are started on an effective treatment regimen, they become less infectious, preventing the spread of disease. The way to achieve universal access to care is through community-based care, he explained. Community-based care takes into account the unique needs of patients, who “have lives, they have kids, they can’t be locked up for two years,” he said. Community-based care provides other much needed services, such as provision of food and other enablers that help patients successfully complete treatment.
Keshavjee encourages people to see TB in a broader view, and recognize that TB is a disease of poverty, which means that decreasing poverty can have an enormous effect on TB control. “TB is a biological phenomenon, but it’s also a social phenomenon,” he said. Socioeconomic interventions can reduce the exposure to TB risk factors, lower the burden of disease, improve screening, and boost treatment success, he said.
He cited the example of Brazil, which has seen a huge decline in TB rates in recent years. Compared to other BRICS countries, MDR-TB levels have remained low in Brazil among both newly diagnosed and rediagnosed diseases, for two reasons: massive poverty reduction efforts and free access to high-quality health care. Thanks to programs like Bolsa Familia, almost forty million people were lifted out of poverty under the presidency of Luiz Inacio Lula da Silva from 2003 to 2011. In the same period, Brazil’s TB rate declined by 50 percent, while the global rate has declined by only 15 percent. In addition, Brazil’s Unified Health Care System has been a comprehensive response to the country’s health challenges.
“I’m not suggesting that we shift our focus away completely from biomedicine to the business of economic development,” he said. “But this shows us that if you have people coming out of poverty you probably get less disease, you’re able to fight disease better, and you have better outcomes if you have disease. This should convince us that we have to think about having some component that invests in the social aspects of TB for our patients as an integral part of every program.”