Tuberculosis - An Old Disease with a New FaceTuberculosis is a global issue
What efforts are being made to fight tuberculosis globally?
Global tuberculosis countermeasures are connected to the eradication of tuberculosis in Japan
Since the development of DOTS, the importance of (TB) countermeasures has been recognized internationally. In today's world, with frequent global travel, the increase of TB in Asia and Africa is not simply “someone else's problem”; this is why a global effort is being made to formulate new strategies to eradicate the disease.
In 1993, the World Health Organization (WHO) issued a TB Emergency Declaration, marking it as a global health emergency, and urged developing and developed countries to work together systematically to tackle the problem.
Recognizing the economic benefit of TB countermeasures using DOTS, the World Bank began granting large-scale financial aid (loans) for TB countermeasures to countries such as China and India.
With the WHO at their core, several public and private groups and organizations came together to form the Stop TB Partnership, which became a powerful supporter for global TB countermeasure promotion, focusing on developing countries.
Japan's proposal at the 2000 G8 summit in Okinawa spread awareness of the fact that contagious diseases were preventing developing countries from growing. The Global Fund to Fight Aids, Tuberculosis and Malaria was established under the leadership of the UN, and began providing significant funding to combat these illnesses.
Developing countries in asia and africa have especially high numbers of patients
Figure 10: Distribution of new TB cases across the world
There are 10.4 million new cases of TB per year worldwide, and 1.4 million people have died from TB (chart/ figure 10)*. These numbers have finally started to slowly decrease in the past few years. Developing countries have the highest number of patients. TB is called a “re-emerging infectious disease” because it just won't go away, and recently, complications such as TB/HIV co-infection and MDR-TB (multidrug-resistant tuberculosis) have become a problem.
When deaths by TB/HIV co-infection are added to the number given in the chart, yearly deaths come to 390,000 worldwide.
Chart: Global TB patient population by region (2015 WHO estimates)
Number of new patients (thousands)
Number of deaths (thousands)*
Rate of HIV positivity among patients (%)
Eastern Mediterranean Region
Western Pacific Region
HIV positivity not included
WHO：Global Tuberculosis Report 2016
TB spreads in HIV positive patients
HIV is a disease that severely weakens the immune system, and is the biggest risk factor for TB. When HIV began to spread in Africa, the number of TB infections increased too.
Additionally, TB countermeasures collapsed in former socialist countries with chaotic social systems; TB cases increased, and malignant (drug-resistant) TB in became a particular problem.
Even in developed countries, TB is becoming a problem again due to the effects of HIV, emerging poverty, and infections brought in from counties where TB is rampant.
What is multidrug-resistant tuberculosis?
The TB bacterium Mycobacterium tuberculosis can become resistant to TB drugs. Multidrug-resistant tuberculosis (MDR-TB) is a strain of TB that has developed resistance to both Isoniazid and Rifampicin, the two most important drugs currently used to treat TB. MDR-TB has recently been increasing globally (including in Japan), and is the most critical issue surrounding the increase of TB today.
Some situations that may lead to the development of MDR-TB are inadequate treatment, irregular drug administration, or drug administration that is suspended before the course is finished. Even after treatment is over and the infection seems to be cured, relapse occurs in around 2-5% of patients*1,2. The right side of Figure 11 (Previously treated patients) shows that such patients often have MDR-TB. Unfortunately, however, anyone infected by an MDR-TB patient will also have MDR-TB from the start (First-time patients, Figure 11 left side).
1Chang, KC. et al.：Am. J. Respir. Crit. Care. Med. 174, 1153-1158, 2006
2Ryoken, IJTLD 19(2), 157-162, 2015
Figure 11: Frequency of MDR-TB in Japan
Courses of treatment for MDR-TB patients
When the main drugs used to treat TB, Rifampicin and Isoniazid (Hydrazide), both become ineffective (multidrug-resistant, MDR), TB becomes extremely difficult to treat. Figure 12 shows research on courses of treatment for MDR-TB patients. Several drugs with severe side effects must be used over long periods of time for this treatment to work. In some cases, surgery is also required. Even so, the results are poor: as shown, recovery was confirmed in 62% of cases, but the remaining cases either ended in death or failed to stop the infection.
Figure 12: Courses of treatment for MDR-TB patients
What is the globally promoted TB treatment system DOTS?
DOTS (Directly Observed Treatment, Short-Course) is a strategy developed by the WHO to ensure that drugs are reliably administered to patients.
With the opinion that international society was taking the TB problem too lightly, Dr. Arata Kochi, who was appointed director of the World Health Organization’s tuberculosis programs in 1989, developed and spread the powerful treatment program known as “DOTS”. This system provides patients in developing countries with a reliable supply of expensive drugs that they could not previously access, and is effective primarily because it requires medical professionals to give the drugs directly to patients and oversee their administration in person.
This system has been adopted not only in developing countries, but also in developed countries such as the US, and has become the world’s standard TB treatment method. In Japan too, the Infectious Diseases Control Law stipulates that “The health care center and attending physician must cooperate to support the patient and ensure that the patient follows through with regular drug administration.” Known as the “Japanese DOTS” system, this process provides and confirms drug administration in ways that fit the circumstances of each patient and region (See “Tuberculosis symptoms”).