Economic Health Care Technology for Developing Countries
Portable Paper Diagnostic Test Dispenser
Marlene Shi
May 17, 2010
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Current Problem
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Global Need in Developing Countries
Case 1: Malaria in tribal belt of Central India
Several hours/days to reach nearest Primary Health Centre
Diagnosis based on clinical symptoms only 50% accuracy
False positives
Blood smears examined by 1 or 2 trained microscopists
NEED: Early diagnosis and prompt treatment
Bharti, PK, N Silawat, PP Singh, MP Singh, and M Shukla. 2008. The Usefulness of a New
Rapid Diagnostic Test, the First Response(R) Malaria Combo (pLDH/HRP2) Card Test, for
Malaria Diagnosis in the Forested Belt of Central India. Malaria Journal. 7, no. 126: [20].
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Global Need in Developing Countries
Case #2: Tuberculosis
Gold standard techniques in infectious disease diagnostics:
microscopy
enzyme-linked immunosorbent assays (ELISA).
tissue culture
lateral flow immunoassays
Problem:
poor detection threshold
expensive
slow
skilled technicians
limited differentiation between multiple pathogens
Hauck, Tanya, Supratim Giri, Yali Gao, and Warren C.W Chan. 2010. Nanotechnology
Diagnostics for Infectious Diseases Prevalent in Developing Countries. Advanced
Drug Delivery Reviews. 62, no. 4/5: 438-448.
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Global Need in Developing Countries
Case #3: HIV
40 million worldwide
96% in developing countries
90% are unaware of having HIV
Transmission of HIV
U.S. Global Health Policy fact sheet. April 2009.
http://www.kff.org/hivaids/upload/3030-13.pdf
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Global Need in Developing Countries
Case #3 WHO
Guidelines for diagnostic tools for infectious diseases
1) Affordable
2) Sensitive
3) Specific
4) User-friendly
5) Rapid and robust
6) Equipment free
7) Delivery to patients
A
S
S
U
R
E
D
Lee, Won Gu, Yun-Gon Kim, Bong Geun Chung, Utkan Demirci, and Ali
Khademhosseini. 2010. Nano/Microfluidics for Diagnosis of Infectious Diseases in
Developing Countries. Advanced Drug Delivery Reviews. 62, no. 4/5: 449-457.
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Global Need in Developing Countries
Case #4 Gates Foundation
Less than 5% of deaths from infectious diseases in developed countries
Over 50% upwards to 95% of deaths in developing countries
Syphilis detection diagnosis
 prevent 215,000 stillbirths
Malaria test
 save over 2 million lives
 prevent 450 unnecessary treatment
Huston, Stu. 2010. To Save Lives, Initiative Pushes for Standardized Diagnosti Tools.
Nature Medicine. 16, no. 1:11.)
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Proposed Solution
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Proposed Solution
Paper diagnostic dispenser
Packaging
Transport
Equipment free
Delivery to patients
Easy reference
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Paper Diagnostic
Technology behind paper…
George Whitesides, Harvard
• Natural spread of fluid
• Hydrophobic polymer
• Reagents in wells
• Color key
Citation:
Healthcare Professionals Network http://medgadget.com/archives/2008/05/pap
erbased_diagnostic_microfluidic_devices.html
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3-branced tree with 2 testing wells .
Glucose and protein assays.
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Paper Diagnostic
Conventional microfluidic device
• Expensive sensors and
analyzers
• External pumps, power
sources
• Etched channels
Citation:
Healthcare Professionals Network http://medgadget.com/archives/2008/
05/paperbased_diagnostic_microfluidic
_devices.html
Whitesides
• Chemical reactions (color)
• Paper natural capillary
action of liquid absorption
• Inherent channels in paper
• Hydrophobic polymer seals
off channels
• Cost of materials: $0.03
• Mass production using
newspaper print technology
Design Schematics
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Design Schematics
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Design Schematics
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Design
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Alternative Designs
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Final Solution Implementation
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Solution Implementation
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Funding Considerations
Gates Foundation:
• “Need common platform for point-of-care diagnostic
devices for use in the developing world.”
• $30 million in grants
(Huston, Stu. 2010. To Save Lives, Initiative Pushes for Standardized
Diagnosti Tools. Nature Medicine. 16, no. 1:11.)
Diagnostics for All (Whitesides Group)
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Validation
“ Improving diagnostic methods, including rapid
diagnostic tests, can reduce costs and enhance
the benefits of effective antimalarial drugs, but
only if the consistency of response to test results
is also improved. Investing in methods to
improve rational response to tests is essential.”
- Lubell, Y, H Reyburn, H Mbakilwa, R Mwangi, and S Chonya. 2008. The
Impact of Response to the Results of Diagnostic Tests for Malaria: Costbenefit Analysis. BMJ. British Medical Journal. 336, no. 7637: 202-205.
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Validation
“ A health care worker of the future is not a
doctor, but an 18 year-old otherwise
unemployed who has two things: a backpack
full of these tests and a lancet to occasionally
take a blood sample – and an AK-47.”
- George Whitesides
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Acknowledgements
Heather Benz
Rahul Kaliki
Sameer Manek
Qing Xiang Yee
Nitish Thakor
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