Second National Drug Resistance Survey on Tuberculosis in the Philippines

TechReport TB

Tuberculosis, or TB, is a contagious disease caused by Mycobacterium tuberculosis which most frequently targets the lungs. The bacteria can be transmitted from person to person by droplet nuclei from the throat and lungs of people with TB. The latest global report of World Health Organization (WHO) in 2012 put estimates of new TB cases at 8.6 million and 1.3 million deaths.

Most cases of tuberculosis are curable, allowing an effective strategy to control the spread of TB to be implemented. Individuals with infectious TB are treated with a full course of the correct dosage of anti-TB medicines that includes isoniazid, rifampicin, pyrazinamide, streptomycin and ethambutol. Due to a lengthy treatment course of 6 to 8 months, WHO recommends a supervised treatment strategy to ensure a regular and uninterrupted intake of medicine called directly-observed treatment, short-course (DOTS). The DOTS strategy is not simply concerned with patient treatment only but is a management strategy for public health systems that incorporates case-detection through high quality bacteriology, standardized short-course chemotherapy, ensuring patient adherence to treatment, adequate drug supply, and monitoring system for program supervision and evaluation, and very importantly, political commitment. A
global strategy anchored on these had enabled countries, especially the high-burden ones, to improve their TB control programs by increasing detection and cure rates and obtaining greater political commitment.

Major obstacles remain in the efforts to achieving global TB control targets. Multiple drug resistance TB (MDR-TB) is one of them. MDR-TB is defined as a form of drug resistant TB due to a M. Tuberculosis resistant to at least both isoniazid and rifampicin, the two most powerful anti-TB drugs. Treatment for MDR-TB is longer than the usual course, using more expensive second-line drugs that have more side effects. MDR-TB management is included in the new and comprehensive Stop TB strategy. An even more serious threat is the emergence of extensively-drug resistant TB (XDR-TB) in patients who are infected with MDR-TB and resistant also to any of the fluoroquinolones and any injectable anti-TB drugs.

The assessment of the spread of anti-TB drug resistance has thus become a necessary component of the global fight to stop TB. Since 1994, the WHO, IUATLD (The Union) and other partners have spearheaded the Global Project on Anti-Tuberculosis Drug Resistance Surveillance (The Global Project). This partnership assists countries in planning the expansion of MDR-TB management using accurate data on national prevalence and patterns of drug resistance. It supports National Reference Laboratories in countries in the conduct of national surveillance for drug resistance using properly selected representative samples of adequate size, data collection and analysis which delineates between new and previously treated cases and internationally accepted methodology and quality control of drug testing. The standardization of these procedures for national surveillance allows global level evaluation of the magnitude and trends in anti-tuberculosis drug resistance. Through these surveys, the growing global burden of MDR-TB has been documented, and in recent years, also the spread of XDR-TB (WHO Global Report 2013).

The Philippines is one of the 22 high burden countries for tuberculosis. In 2012, there were approximately 450,000 cases with 23,000 deaths. This corresponded to 461 existing cases of TB and 24 deaths per 100,000 population in the country. Incident cases of TB were counted at 265 per 100,000 populations (WHO Global Report 2013).

Programmatic management of multi-drug resistant TB was started in 1999 by the Tropical Disease Foundation (TDF) through the TDF – Makati Medical Center (MMC) DOTS Clinic. In 2003, the Philippines received funding support from the Gobal Fund to Fight AIDS, TB and Malaria (GFATM) with the TDF as principal recipient to treat MDRTB cases. First covering the National Capital Region, additional treatment centers were set-up. Local government units (LGUs) and other partners were then engaged by working with the Center for Health Development (CHD) and other partners by referring MDR-TB suspects to the treatment centers. These LGUs were also expected to provide continuing MDR-TB care. Significantly, the National TB Reference Laboratory (NTRL) was designated as the lead agency in the establishment of a laboratory network in the Philippines. In 2008, the National Implementing Guidelines for the Programmatic Management of Drug-Resistant TB (PMDT) was signed by the Secretary of Health. The principal recipient
designation by GFATM was transferred from the TDF to Philippine Business for Social Progress (PBSP) in 2010 and necessary adjustments were implemented. There are 44 PMDT facilities in the country located in 16 regions (Lofranco, unpublished report).

The Philippines conducted its first National Drug Resistance Survey in 2004 employing the recommended procedures of the WHO and The Union (Philippine Nationwide Tuberculosis Drug Resistance Survey Team [PNTDRST], 2009). In this survey they reported that the prevalences of the different forms of anti-TB drug resistance were high. Resistance to any drug was 20.40% in new TB cases and 38.80% in previously treated TB cases. Multi-drug resistant TB prevalence was 3.80% and 20.90%, respectively, among the two groups of TB patients. Funded by the Global Fund Project “Sustaining TB Control and Ensuring Universal Access to Comprehensive Quality TB Care”, the 2nd National Drug Resistance Survey (DRS) started in 2011 and was completed in 2012. This report presents the results of this study.

Download the full version of the Second National Drug Resistance Survey on Tuberculosis Technical Report (June18.2015) here.