SEATTLE — According to the Centers for Disease Control (CDC), the prevalence of drug-resistant tuberculosis is expected to increase worldwide over the next two decades. Four countries in particular — Russia, India, the Philippines, and South Africa — are home to 40 percent of all tuberculosis cases. The rise of drug-resistant TB would have a substantial negative impact on mortality and poverty rates.
Multidrug-resistant tuberculosis (MDR-TB) is resistant to isoniazid and rifampin, the two most commonly used and potent TB drugs. Extensively drug-resistant tuberculosis (XDR-TB) is resistant to these two drugs plus fluoroquinolone and at least one of three injectable second-line drugs. Treatment options for XDR-TB patients are limited and less effective. MDR-TB and XDR-TB are spread through the air, and can also develop when medication for TB is not taken correctly.
By 2040, MDR-TB is expected to comprise 5 percent of TB cases in Russia, India, the Philippines and South Africa, with estimates for Russia reaching as high as 32 percent of TB cases. XDR-TB is anticipated to account for nearly 10 percent of TB cases in all four countries by 2040. This rise of drug-resistant TB will be primarily airborne rather than acquired drug resistance. Treatment for non-resistant TB takes approximately six to nine months compared to up to two years for drug-resistant TB. Worse, fatality rates are close to 30 percent for MDR-TB and 80 percent for XDR TB. And, as drug-resistant cases arise, the potential for the rise of totally resistant TB, for which fatality is 100 percent, becomes an increasing concern.
Those in poverty are at an extremely high risk for drug-resistant TB. Lack of access to healthcare facilities can delay diagnosis and increases the likelihood of not completing the entire treatment regimen. The high prevalence of comorbidities, such as HIV, as well as crowded living conditions and poor sanitation, are also factors.
One low-income country has successfully combated the rise of drug-resistant TB. Peru is a hotspot for the disease; the country has the highest incidence of TB in the Americas, as well as 35 percent of MDR-TB cases and 75 percent of XDR-TB cases in the region. But Peru also boasts the highest cure rate for TB, with 87 percent of new cases cured and 66 percent of XDR cases cured, compared to a 28 percent global cure rate for XDR-TB.
In addition to a surveillance system established by the Peruvian Ministry of Health, a partnership with the NGO Partners in Health resulted in a TB detection laboratory, which allows for faster and more accurate diagnosis of the disease. Partners in Health also helped establish a community-based program for health workers to regularly check in with TB patients at their homes to ensure treatment adherence. And, the government pledged to cover nearly 80 percent of the cost of TB treatment, lifting a huge economic barrier.
The rise of drug-resistant TB is a major concern globally, particularly for those in poverty. Adoption of community-based programs like Peru’s in Russia, India, South Africa and the Philippines is an important step in ensuring proper care and treatment of TB and combating the rise of drug-resistant TB.
– Nicole Toomey