Key findings from the research
- Developed an affordable genetic diagnostic kit
- Enabled early diagnosis of tuberculosis and African trypanosomiasis
- Produced a practical proposition for developing countries
This research project was conducted as part of the SATREPS (Science and Technology Research Partnership for Sustainable Development) (Note 1) program run by JST and JICA. Researchers led by Professor Yasuhiko Suzuki of the Research Center for Zoonosis Control at Hokkaido University developed rapid diagnostic techniques for tuberculosis (Note 2) and African trypanosomiasis (Note 3) that are affordable and easy to use, and represent a practical proposition for developing countries. The technology was introduced to the Republic of Zambia, enabling researchers and technologists there to conduct research and perform diagnostic tests independently in their own country.
There was a need to develop a definitive diagnostic procedure for tuberculosis that is simple, affordable, and fast. Conventional tuberculosis detection, achieved through the culture of tuberculosis pathogens in sputum, is cumbersome, comes with a risk of infection in the laboratory, and has a long wait time of approximately one month to determine the results. There was also a need to develop a highly sensitive, rapid diagnostic technique for African trypanosomiasis, because conventional testing involves looking for trypanosomes in blood under a microscope, a low-sensitivity approach that does not allow early detection.
By applying the LAMP (Loop Mediated Isothermal Amplification) method (Note 4), the research group successfully developed a technology that rapidly detects the genes of tuberculosis and trypanosomes in clinical specimens at a cost of about 100 yen per specimen.
Using this technology, affordable, early diagnosis of tuberculosis and African trypanosomiasis becomes possible, enabling appropriate treatment to begin soon after the onset of the disease. This will improve treatment rates, leading to a reduction in the number of fatalities caused by these infectious diseases, and contributing to a major reduction in the number of patients afflicted by them.
A SATREPS project involving collaboration with the University Teaching Hospital of the Republic of Zambia's Ministry of Health and the University of Zambia's School of Veterinary Medicine, this research was conducted by a group including Associate Professor Kiichi Kajino of the Research Center for Zoonosis Control at Hokkaido University and Takashi Matsuba, lecturer at Tottori University.
Outline of the research project
This research project was conducted as part of the SATREPS (Science and Technology Research Partnership for Sustainable Development) program run by JST and JICA.
- Research area: Research on measures to address infectious diseases control attuned to the needs of developing countries
- Project title: Establishment of Rapid Diagnostic Tools for Tuberculosis and Trypanosomiasis and Screening of Candidate Compounds for Trypanosomiasis
- Principal Investigator: Prof. Yasuhiko Suzuki (Research Center for Zoonosis Control, Hokkaido University)
- Research period: October 2008 - March 2014
This research project developed rapid diagnostic techniques for tuberculosis and trypanosomiasis, as well as rapid drug susceptibility testing techniques for tuberculosis, and assessed performance of the techniques in the Republic of Zambia using specimens derived from within Zambia. Researchers also screened candidate substances for drug development through the synthesis of candidate substances with therapeutic potential for trypanosomiasis and assessed their efficacy using trypanosome culture systems.
Overview of the research
Newly emerging and re-emerging infectious diseases are a global threat, including infections such as tuberculosis, transmissible bovine spongiform encephalopathy (BSE), SARS, Nipah virus, hantavirus, Hendra virus, and new strains of influenza, as well as Ebola hemorrhagic fever, pneumonic plague, and leptospirosis.
A particularly urgent need exists for action with regard to tuberculosis, which is thought to infect one third of humanity and produces approximately 9 million new cases and 1.4 million deaths annually. Tuberculosis is a particular problem in Asia and Africa, with three fourths of the world's TB patients said to be concentrated in those regions. African trypanosomiasis is endemic in sub-Saharan Africa, and is estimated to be responsible for approximately 5 million deaths each year. Early differential diagnosis is important because it is frequently misdiagnosed as being another type of febrile illness, such as malaria, and develops into a severe condition in many cases due to inappropriate treatment.
Under these circumstances, there is a vital and urgent need for appropriate treatment based on diagnostic results achieved through the development and adoption of a simple, affordable diagnostic technique. There was demand for development of a definitive diagnostic procedure for tuberculosis that is simple, affordable, and fast, because conventional tuberculosis detection involving the culture of tuberculosis bacteria in sputum is cumbersome, comes with a risk of infection in the laboratory, and has a long wait time of approximately one month to determine the results. There was also demand for development of a highly sensitive, rapid diagnostic technique for African trypanosomiasis, because conventional testing involves looking for trypanosomes in the blood under a microscope, a low-sensitivity approach that does not allow early detection.
This research group achieved the following results by conducting research aimed at developing a highly sensitive, rapid diagnostic technique that is simple, affordable, and a practical proposition for developing countries.
1) By applying the LAMP (Loop Mediated Isothermal Amplification) method, we developed simple, affordable technology that rapidly detects the genes of tuberculosis bacteria and trypanosomes in clinical specimens.
2) We developed a diagnostic kit, with a low cost of about 100 yen per specimen, in which all reagents are in dry form in order to make handling practicable in developing countries that do not have complete cold chain distribution systems.
3) We developed a low-cost, compact fluorescence detector (costing approximately 3,000 yen) to enable clearer determination of test results.
Prospects and further research
Using this technology, early diagnosis of tuberculosis and African trypanosomiasis becomes possible, which will result in appropriate treatment beginning at an early stage. Making early treatment possible will lead to a reduction in the number of deaths caused by these infectious diseases, and contribute to a major reduction in the number of patients afflicted by them.
The African trypanosomiasis diagnostic technique is already coming into use for the diagnosis of actual patients. The tuberculosis diagnostic technique has entered the assessment testing stage, in order to receive approval by the Republic of Zambia as an official analytical method. Assessment is being conducted by a team based at the University Teaching Hospital under the supervision of the Republic of Zambia's Ministry of Health. This technology has attracted interest and inquiries from Zambian organizations, and there are plans for collaboration with the WHO and private sector corporations.
Figure 1. Dry LAMP kit for diagnosing tuberculosis
The colored substance is the dry, immobilized reagent for tuberculosis diagnosis.
Figure 2. Outcome of looking at test results with the unaided eye
Blue indicates positive, purple negative.
Figure 3. Low-cost, compact fluorescence detector
Powered by four size AA batteries, making it usable for diagnosis in regions without electricity.
Figure 4. Test results using a low-cost, compact fluorescence detector
Demonstrably clearer than when viewed with the unaided eye.
Notes and terminology
Note 1: SATREPS
SATREPS (Science and Technology Research Partnership for Sustainable Development) is a Japanese government program that promotes international joint research to address global issues through three- to five-year projects involving partnerships between researchers in Japan and researchers in developing countries. The program is collaboration between Japan Science and Technology Agency (JST) and the Japan International Cooperation Agency (JICA). JST uses research contracts to support research costs incurred in Japan (and in other locations outside the developing country involved in the project). JICA provides support through its technical cooperation project framework to cover costs in the developing country. Overall R&D management of the international joint research is handled jointly by JST, which has expertise in funding research projects at research institutions in Japan, and JICA, which has expertise in technical cooperation in developing countries. Details are available at the JST website: http://www.jst.go.jp/global/english/about.html
Note 2: Tuberculosis
Tuberculosis is an infectious disease caused by tuberculosis bacteria, and thought to infect approximately 2 billion people around the world. In 2011, approximately 9 million new cases and 1.4 million deaths were reported worldwide, including 22,681 cases and approximately 2,166 deaths in Japan.
Note 3: African trypanosomiasis
African trypanosomiasis is an infectious disease caused by the parasitic trypanosome protozoan transmitted by the tsetse fly. Seen in sub-Saharan Africa, it is estimated to be responsible for approximately 5 million deaths annually. Although treatable if detected early, the fatality rate among patients with central nervous system manifestations is said to be almost 100%. No infections are known to have occurred in Japan, but diagnosis is required for people returning to Japan from Africa who are suspected of having developed the disease.
Note 4: LAMP
Loop Mediated Isothermal Amplification (LAMP) is a method developed by Eiken Chemical Co., Ltd. for greatly amplifying genetic fragments under isothermal conditions.
Concerning the research:
Professor, Research Center for Zoonosis Control, Hokkaido University
Concerning the SATREPS program (JST):
Research Partnership for Sustainable Development Division
Japan Science and Technology Agency
Concerning the SATREPS program (JICA):
Office of Media and Public Relations
Japan International Cooperation Agency