Washington — The pace of progress in the intense battle between global public health officials and Mycobacterium tuberculosis — the cause of an airborne infectious disease epidemic that killed 1.7 million people in 2006 — slowed during that year, according to the World Health Organization (WHO).
Global Tuberculosis Control 2008, released March 17, describes a decline in tuberculosis (TB) diagnosis, a slight rise in global cases since 2005, the highest levels ever recorded for multidrug-resistant TB and a lethal combination of TB and HIV/AIDS that is fueling the TB epidemic in parts of the world, especially Africa.
The 12th annual WHO report on global TB control was released in advance of World TB Day, observed March 24, and is based on data from 202 countries and territories.
March 24 commemorates the day in 1882 when German physician and Nobel laureate Robert Koch announced his discovery of the bacillus that causes TB. The disease was raging through Europe and the Americas at the time, killing one in seven people.
According to the WHO report, the 9.2 million new cases of TB in 2006 included 700,000 cases among people living with HIV, and 500,000 cases of multidrug resistant TB. An estimated 1.5 million people died from TB in 2006 and another 200,000 people with HIV died from TB. (See “Highest Recorded Rates of Drug-Resistant Tuberculosis Reported.”)
TB is difficult to control, Dr. Michael Iseman, senior staff physician in the Infectious Disease Division at National Jewish Medical and Research Center in Denver, told America.gov, because of a clever pathogenic strategy.
“There is an immense reservoir of latent [dormant] infection in tuberculosis,” said Iseman, one of the world’s experts on diagnosing and treating tuberculosis, especially drug-resistant TB. “It is estimated that roughly half the world has latent infection in their bodies, but the majority of people who are not HIV infected never develop active disease.”
109 YEARS OF TB TREATMENT
The nonsectarian National Jewish Center, one of the best hospitals in the world for respiratory diseases, has been treating TB since 1899 and drug-resistant TB since the 1990s.
Several components make it outstanding, Iseman said, including a diagnostic laboratory that helps determine the best treatment for each patient. “It’s custom-tailored therapy instead of guessing, Iseman said. “We’re blessed to be able to do it the right way.” Other important elements include a team of experienced clinicians, a laboratory that can test a patient’s blood for correct drug dosing levels, skilled surgeons who can safely remove damaged lung tissue and a physical environment that is safe for physicians, nurses and patients.
Tuberculosis requires a monthslong course of treatment with several first-line (most effective) drugs. A patient who does not take the first-line drugs correctly can develop multidrug-resistant (MDR) TB. For MDR-TB, patients take less effective, more toxic second-line drugs. If these are not taken correctly, patients can develop extensively drug-resistant TB, a virtually untreatable condition that also can spread to healthy people.
To make sure patients take their medication properly, Iseman said, “the principle popularized here in Denver was, ‘You’ve got TB. This is not like high blood pressure or diabetes. You don’t have the option of taking your medicine or not.’”
The practice in the United States, he added, is to have a health care provider watch patients take their medicine, either by having patients come to the hospital or by sending someone out to the patients.
“It’s paternalistic as hell,” Iseman said, “but it worked and that’s why we have cut case rates in America in half over a decade. It’s a phenomenal success story that hasn’t been widely appreciated.”
A similar principal is at the heart of the WHO Stop TB Strategy. DOTS (directly observed treatment-short course), Stop TB spokesman Glenn Thomas told America.gov, includes five elements.
These are political commitment with increased and sustained financing, case detection through quality-assured bacteriology, standardized treatment with supervision and patient support, an effective drug supply and management system, and monitoring and evaluation.
In the “supervision and patient support” element, Thomas said, “supervision is also called DOT in some countries. It implies the task, by the health system, to ensure patients take their drugs as prescribed, daily or every other day [depending on the country], and for the total duration of treatment [usually six months for drug-susceptible TB].”
Such supervision can be realized through health workers in a clinical facility or through community workers or even volunteers that can support the patient.
“These individuals watch patients taking their drugs, while supporting them,” Thomas said. “Many different solutions exist, and all have the final aim to help patients go through their treatment effectively, thus getting cured and preventing the creation of drug resistance due to errors in treatment.”
Patient support, he said, is paramount and crucial. WHO promotes a patient-centered approach that facilitates support, education and counseling to make all patients more responsible for the proper conduct of their long treatment.
More information about tuberculosis, and TB and HIV/AIDS, is available online through the U.S. Centers for Disease Control and Prevention, the President’s Emergency Plan for AIDS Relief, the National Institute of Allergy and Infectious Diseases, the World TB 2008 Web site, and the WHO Stop TB Partnership. Courtsey : Cheryl Pellerin