News

The Sanatorium Files: Part 4 – DOTS


14 Jul 2010
by Working Group

Connecting the DOTS: Unprecedented Approach to Ensure Compliance

This is the fourth in our series “The Sanatorium Files.”

Throughout this series we’ve taken an in-depth look at how tuberculosis has been diagnosed and treated with folk cures and sanatorium stays throughout history, and the scientific development in the last century that led to the first cure and development of effective drugs that could kill M. tb. We round out the series with this post on the most recent development in the treatment of TB: an unusual and unprecedented public health program to ensure compliance with the TB drug regimen called directly observed therapy, short course (DOTS).

DOTS is the current standard of care for infectious pulmonary TB, endorsed by the World Health Organization (WHO). It is a strategy that relies on direct supervision of patients taking their TB medication every day for the best results of the treatment and to help limit the development of resistant strains that can emerge when medication is stopped prematurely.

DOTS was developed in the 1980s by Karel Styblo of the International Union Against Tuberculosis and Lung Disease, and was soon proven effective in Africa among poor and illiterate populations. The World Health Organization first endorsed the strategy in 19861, and then in 1993 the WHO declared TB to be a global emergency and recommended DOTS worldwide as the best approach for treatment and containment.2

DOTS is based on five components2:

  • Government commitment to long-term TB control programs
  • Case detection by sputum smear microscopy in all treated patients
  • Standardized treatment regimen directly observed by a healthcare worker or community health worker for at least the first two months (the short course)
  • A regular, uninterrupted drug supply
  • A standardized recording and reporting system that allows assessment of treatment results by the country and WHO

DOTS Every Day

Under the DOTS program, TB patients are allowed to continue their lives, but every day they are visited by a health worker who gives them their treatment of several TB drugs and watches to be sure they take them all. The personal connection with a health worker can help encourage compliance, but it is a constant challenge to keep track of every patient and their status.

“Ideally, health-care workers meet patients at prearranged spots to carry out their supervisory tasks. The job is often more complicated, however, with workers expending much time and energy tracking down the patient to a new job, a friend’s home, or even a crack house and then relying on arguments and ingenuity to convince the person to take their daily medication.”3

DOTS workers often use incentives or even bribes to coerce their charges to stick with their treatment: a hot meal, vouchers for public transportation or groceries, treats for the children, overnight rooms for the homeless, birthday cakes and other treats, and even cash. The ultimate goal is to keep each TB patient in treatment, taking their medication every day, for the full course needed to wipe out the TB and eliminate the risk of resistance developing.

DOTS Results

DOTS has become a very successful TB control strategy. It is in operation in 192 countries and has decreased epidemics and new infections in many of them.2 Worldwide, DOTS has a nearly 80 percent cure rate, and the rates of drug-resistance had dropped as well.4

“Cure rates of up to 95 percent have been reported in even the poorest countries. In parts of China, DOTS has produced 96 percent sure rates among new cases, and in Peru, use of DOTS for more than 5 years has led to successful treatment of over 90 percent of cases and a decline in overall numbers of infection. In New York City, new cases of TB went down by 65 percent between 1993 and 2004, largely due to DOTS. Drug resistant cases fell by over 90 percent.”3

DOTS Challenges

Though DOTS has shown very positive results when implemented correctly, it is far from a perfect solution for TB. First of all, it is labor intensive and very expensive. Though a standard course of TB drugs costs an average of just $10 per patient5, adding the cost of a dedicated health worker or each patient increases the cost exponentially.

The cost and logistics for countries to implement DOTS is also an impediment to implementation, because it requires secure, uninterrupted access to enough TB medications and a public health infrastructure to manage the program.

In addition, the DOTS program by its nature excludes entire categories of TB patients. Because the program relies on a positive test of sputum coughed up from the lungs to determine who is treated, children, who are not strong enough to cough up sputum and people who are too sick and weak to cough up sputum are excluded from the program. People with TB in organs other than the lungs also are excluded (though these forms are not usually infectious). Doctors without Borders specifically has been vocal in its concern about these exclusions. In response, WHO expanded its DOTS strategy in 2002 and specifically stated that every person has the right to TB care.2

DOTS-Plus

Drug resistance continues to pose a significant challenge to DOTS and TB treatment. In 1998, the Open Society Institute commissioned the Harvard Medical School’s Department of Medicine to study the growing problem of multi-drug-resistant TB. Two Harvard physicians, Paul Farmer and Jim Kim, with the help of many others who were active in the global TB arena, put together a massive report, titled The Global Impact of Drug-Resistant Tuberculosis.1

“Farmer, the lead author of the report, stressed that the World Health Organization’s DOTS strategy must be used, together with a program offering second-line drugs for people with multi-drug-resistant TB. He explained that DOTS works only for people with drug-sensitive TB; when TB is already drug-resistant, DOTS can actually promote more drug resistance.

In Lima, Peru, he and his colleague Dr. Jim Kim had seen that DOTS was failing in a community where multi-drug-resistant TB was common. They began testing patients for drug resistance and treating them with the expensive second-line drugs to which their TB was sensitive. With perseverance and by cajoling drug manufacturers and distributors, Farmer and Kim managed to get the second-line drugs somewhat more cheaply. They were beginning to succeed in saving lives and stopping the spread of multi-drug-resistant TB.” 1

Dr. Arata Kochi, then head of the WHO Stop TB Partnership, called the new program DOTS-PLUS. 1 The organization has a DOTS Expansion Working Group working to further advance towards universal access to quality TB care for all people with TB, adults and children especially the poor and vulnerable.

Though DOTS has made significant impact on the TB epidemic, it requires a long-term commitment to personnel and funding and continues to rely on tuberculosis drugs that were developed more than 40 years ago. We at the Working Group for New TB Drugs look forward to the day that the efforts of today’s TB researchers will provide new and more effective treatments for this epic disease that will put us back ahead of M. tb permanently.

Sources: 1 “Timebomb: The Global Epidemic of Multi-Drug-Resistant Tuberculosis” by Lee B. Reichman, MD, MPH, and Janice Hopkins Tanne, 2002, McGraw-Hill; p. 115, 85-86.

2 “Tuberculosis” by Toney Allman, 2007, Lucent Books/Thomson Gale; p. 78, 79.

3 “Tuberculosis” by Diane Yancey. Text copyright © 2008 by Diane Yancey. Reprinted with the permission of Twenty-First Century Books, a division of Lerner Publishing Group, Inc.; p. 74-75. All rights reserved. No part of this text excerpt may be used or reproduced in any manner whatsoever without the prior written permission of Lerner Publishing Group, Inc.

4 “The Tuberculosis Update” by Alvin and Virginia Silverstein and Laura Silverstein Nunn, 2006, Enslow Publishers, Inc.; p. 65.

510 Facts About Tuberculosis,” The International Union Against Tuberculosis and Lung Disease.

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