Pilot Study: Foldscope & Microfluidics
Title: Foldscope & Microfluidics: Accessible Diagnostics for Community-led Schistosomiasis Control
Collaborators/Co-Investigators & Institutional Affiliation:
Heath in Your Hands Team
Dr. Olubodun - Federal Medical Center Abeokuta, Ogun State (Senior Investigator)
Dr. Adebayo - Federal Medical Center Abeokuta, Ogun State
Dr. Adedayo - Federal Medical Center Abeokuta, Ogun State
Dr. Ekpo - Federal University of Agriculture, Abeokuta (FUNAAB), Nigeria
Dr. Oluwole - Sightsavers
Dr. Mogaji - Federal University Oye-Ekiti, Nigeria
Dr. Stafford - UTHealth Science Center at Houston
Dr. Lee - UTHealth Science Center at Houston
Dr. Tebo - UTHealth Science Center at Houston
Dr. Prakash - Stanford University, Foldscope Instruments
Dr. Cybulski - Stanford University, Foldscope Instruments
Dr. Moreno-Roman - Stanford University, Foldscope Instruments
Students, lab techs, and everybody involved will be listed accordingly
List of Abbreviations
CHEW: Community Health Extension Worker
FGD: Focus Group Discussion
FGS: Female Genital Schistosomiasis
HIYH: Health in Your Hands
HPV: Human Papillomavirus
KII: Key Informant Interview
LGA: Local Government Area
NPV: Negative Predictive Value
NTD: Neglected Tropical Disease
OGHREC: Ogun State Health Research Ethics Committee
PPV: Positive Predictive Value
WHO: World Health Organization
Protocol/Proposal Summary
This study aims to evaluate the effectiveness of the Foldscope, a low-cost paper microscope, for diagnosing Schistosoma haematobium in urine samples within rural Nigerian communities, particularly in rural Ogun state. The project will assess diagnostic accuracy, community acceptability, and feasibility of implementation through collaboration with local community health extension workers (CHEWs) and volunteers.
The study will compare Foldscope-based microscopy workflow with conventional methods, focusing on the effectiveness and accuracy of this diagnostic tool paired with a reusable microfluidic device for trapping eggs in urine. Additionally, we will measure feasibility and community acceptability using a mixed-methods approach including focus group discussions and key informant interviews.
The research will be conducted in selected rural communities near the Oyan River Dam in Ogun State, with a sample size of 365 participants. The study employs a cross-sectional design with both quantitative and qualitative components to evaluate the diagnostic tool's performance.
The expected benefit is the development of a sustainable, community-based diagnostic solution that could improve schistosomiasis surveillance in resource-limited settings, potentially transforming community-based disease detection and treatment strategies.
Chapter 1: Introduction
Background
Schistosomiasis is a significant public health issue in Nigeria, particularly in rural areas where access to diagnostics and treatment is limited by numerous barriers. Urogenital schistosomiasis is prevalent in rural areas where people rely on natural freshwater, with transmission depending on the abundance of the primary snail host (Ezeh et al., 2019). While Schistosoma haematobium infection is currently diagnosed mainly via traditional light microscope inspection of urine, the Foldscope presents an opportunity to provide low-cost, portable diagnostics, potentially transforming community-based disease detection and treatment strategies (Ephraim et al., 2015). However, there is a need to evaluate the use of the Foldscope for this purpose in the hands of community health extension workers (CHEWs) in rural settings, to better understand how this may be incorporated into control strategies. Additionally, there is no current suitable option for sample preparation that is cost-effective and does not require electricity. In the present study, we aim to fill these gaps in current knowledge.
Statement of the Problem
Studies have found the highest prevalence rates of schistosomiasis in school-aged children and young women, and high prevalence of urogenital schistosomiasis in Nigeria in many endemic states despite ongoing mass drug administration with praziquantel (Ezeh et al., 2019; Archer et al., 2024; Faust et al., 2021; Mtethiwa et al., 2015). Classic symptoms include hematuria, abdominal pain, and fatigue (WHO, 2023). Of particular concern is the development of female genital schistosomiasis (FGS), which can harm female reproductive organs and increase the risk for infertility, and HPV infection. FGS has been highly associated with bladder cancer, particularly squamous cell carcinoma and cervical cancer, which is associated with high rates of HPV infection in patients with FGS (Chatterji et al., 2024).
Geographical, financial, social and educational barriers currently prevent adequate diagnosis and screening in hyper-endemic (>50% endemicity) zones of schistosomiasis in Nigeria, including Ogun state (Ezeh et al., 2019). Traditional testing methods require trained personnel, costly lab equipment, and centralized facilities, making them less accessible. In rural communities, long travel distances to healthcare facilities and high costs associated with services deter individuals from seeking diagnosis (Van et al., 2020; Dawaki et al., 2015). This is exacerbated by limited awareness of schistosomiasis, limited recognition of the presenting symptoms by healthcare workers, as well as social stigma surrounding the presenting symptoms, leading to delays in seeking healthcare for those affected (Faust et al., 2020; Van et al., 2020; Dawaki et al., 2015). Local scholars point to a gap between policy-making and control measures for schistosomiasis, as well as a lack of clarity about the number of people affected by S. haematobium infection in endemic areas, making epidemiological data difficult to determine (Ezeh et al., 2019).
Justification/Significance of the Study
As schistosomiasis poses multifactorial challenges, a community-based, low-expense solution for diagnosing Schistosoma haematobium in urinary samples is needed. The project aims to work with local health workers in Foldscope-based microscopy, comparing its diagnostic accuracy, cost-effectiveness, and community acceptability to conventional microscopy methods. By empowering communities to diagnose schistosomiasis in a way that would reduce financial and travel barriers, this initiative aims to contribute to schistosomiasis control efforts.
We will also assess the use of a reusable microfluidic device capable of trapping Schistosoma haematobium eggs (Xiao et al., 2016) as the slide containing the urine sample, in order to evaluate the utility of trapping the eggs from urine mechanically as opposed to relying on centrifugation or expensive filtering, which relies on expensive equipment. To enhance the impact and scalability of this project, we aim to partner with national, state, and local leadership in Nigeria, and individuals already engaged in relevant public health and research initiatives, to build on existing work that has been done.
Our proposal is to evaluate the effectiveness of the Foldscope microscope and a microfluidic slide as diagnostic tools in Nigerian regions impacted by Schistosoma haematobium, starting with communities near the Oyan River Dam in Ogun State, where there is a recorded high-burden of this disease (Akinwale, 2010; Ekpo, 2012). Findings from this study could aid in further research to inform the development of scalable diagnostic strategies for rural settings incorporating accessible tools, communication, and education into control efforts.
Chapter 2: Research Objectives
2.1 General Objective
The central objective is to evaluate the use of Foldscope-based microscopy in an endemic area within a community of known high prevalence, comparing its diagnostic accuracy, cost-effectiveness, and community acceptability to conventional microscopy methods. With collaboration from local leadership, we aim to evaluate:
The effectiveness of the Foldscope (Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy)
Feasibility (using a mixed-methods approach)
Community acceptability & barriers of this Foldscope-based microscopy workflow in the diagnosis of genitourinary schistosomiasis caused by Schistosoma haematobium
2.2 Specific Objectives
To determine the effectiveness of Foldscope microscopy for Schistosoma haematobium detection, as measured by sensitivity, specificity, PPV, NPV, and accuracy of this diagnostic tool, as well as the level of agreement between trained lab scientists and CHEWs using the Foldscope.
To assess community feasibility of implementation, and opportunities for educational interventions for community health extension workers (CHEWs).
To assess acceptability and barriers encountered using the Foldscope in this clinical setting vs. conventional methods, as measured by focused group discussions (FGDs), structured in-depth interviews, and key-informant interviews (KIIs) with community leaders and current control effort leaders.
Chapter 3: Research Methods
3.1 Study Design
This is a mixed methods cross-sectional study aimed at evaluating Foldscope-based microscopy against conventional diagnostic methods. All samples will be examined with the current gold standard in addition to the experimental process. It will also incorporate qualitative research components to assess community perceptions and implementation feasibility.
3.2 Study Area
This study will be conducted in Ogun State, Nigeria, specifically within the Imala Odo and Imala communities near Oyan River Dam to begin with. These communities have been selected due to their varying prevalence rates of schistosomiasis, with Imala Odo showing high prevalence (greater than 90% from unpublished reports) and Imala showing decreasing prevalence. The study will be conducted in rural communities within two local government areas in Ogun State.
3.3 Study Population
The study will involve three distinct populations:
Community members for diagnostic testing:
Individuals aged 5 years or older with a history of freshwater exposure, recent travel from endemic areas, or hematuria/urinary symptoms
Must be able to provide informed consent (or guardian consent for minors)
Capable of providing a urine sample of at least 30 mLs
Healthcare workers for feasibility assessment:
Community health extension workers (CHEWs), lab scientists, technicians, nurses, or other clinicians
Willing to participate in both the diagnostic testing phase and the qualitative evaluation phase
Key stakeholders for acceptability assessment:
Adults residing in rural communities in the study area
CHEWs or clinicians from the study communities
Other stakeholders with experience in schistosomiasis control (State & Local NTD coordinators, Medical Officers of Health, lab scientists or technicians)
Must have been involved with schistosomiasis control efforts in the past
3.4 Sample Size Determination
3.4.1 Diagnostic Accuracy Component
First, we assessed the current average prevalence of schistosomiasis in Oyan River Dam communities as 52% based on the existing literature (Akinwale, 2010; Ekpo, 2012). The formula for calculating the required sample size for sensitivity estimation in a diagnostic accuracy study was applied as follows, assuming a finite number of population of 1600 individuals since we are focusing on two communities with a limited population:
N =Z2* Se * (1-Se)d2 * P
Where:
N = Minimum required number of infected individuals
Z = Standard normal deviate corresponding to a 95% confidence level (1.96)
Se = Expected sensitivity of the diagnostic test (assumed 80% or 0.80)
d = Desired precision (5% or 0.05)
P = Prevalence of infection in the study population (52% or 0.=52)
Substituting values:
N =(1.96)2* 0.80* (1-0.80)(0.05)2 * 0.52
N 473
To adjusted for a finite population of 1600, we will apply to finite population correction:
Nadjusted =N1 + (N/ Npopulation)
Substituting:
Nadjusted =4731 + (473/1600) = 365
Thus, we will aim to recruit 365 people for this study.
Assumptions and Considerations:
The expected sensitivity of the Foldscope is assumed to be 80% based on preliminary estimates.
The 52% prevalence is a liberal estimate that represents historically high infection rates (Ekpo, 2012) observed in Oyan Reservoir communities, but this is likely far higher than the existing situation today in Imala, while Imala Odo likely faces much higher prevalence. There is a lack of existing up-to-date data in this region, so we are using this number to reflect an approximate average for the region based on existing data.
A 5% precision margin aligns with standard diagnostic accuracy study methodologies.
The study is primarily focused on sensitivity estimation; specificity assessment is exploratory and may be limited due to the high prevalence of infection.
Thus, we will aim to recruit 365 people to be included for this study.
Assumptions:
The expected sensitivity of the Foldscope is assumed to be 80% based on preliminary estimates
The 52% prevalence represents an approximate average for the region based on existing data
A 5% precision margin aligns with standard diagnostic accuracy study methodologies
A 10% buffer will be added to account for potential dropout rates, meaning 400 in total as a goal for recruitment, meaning 50 people per day over an 8 day period.
3.4.2 Qualitative Components
For the qualitative data collection:
10-20 CHEWs/clinicians will be recruited for in-depth interviews
8-12 participants for each focus group discussion (FGD)
A minimum of one CHEW/clinician focus group
Additional key informant interviews (KIIs) with stakeholders involved in schistosomiasis control
3.5 Sampling Methods
3.5.1 Diagnostic Accuracy Component
Participants will be selected via convenience sampling. Over the course of eight days at the study sites (distributing approximately 50 participants per day for timing considerations), participants will be recruited by community mobilizers and Health In Your Hands (HIYH) team members to attend a screening clinic. The screening clinic will be set up at locations chosen by community leadership, such as local primary schools or community meeting centers.
3.5.2 Qualitative Components
Healthcare workers will be recruited via convenience sampling from Imala, Imala Odo, and surrounding communities
FGD participants will be collected via convenience sampling (8-12 participants per group)
Key informants will be identified during the study and invited for interviews
3.6 Data Collection Methods
3.6.1 Diagnostic Accuracy Component
At least 30 mL of urine will be collected from each participant
10 mL will be used for the gold standard diagnostic technique (microfiltration with polycarbonate membranes followed by standard light microscopy)
The remaining urine sample will be used in the experimental arm using the microfluidic device and Foldscope microscope
CHEWs and clinicians will conduct processing and diagnosis in the experimental arm after receiving appropriate training
Each participant will provide a "positive" or "negative" determination based on the identification of eggs
Egg counts will be performed with both methods to evaluate quantitative assessment capabilities
Quality control will include 3 lab scientists per lab table for verification, level of agreement will be measured by recorded assessments
Positive cases will be treated immediately with praziquantel
3.6.2 Qualitative Components
CHEWs/clinicians will participate in in-depth interviews lasting 30-60 minutes after completing the diagnostic component
Focus group discussions will be conducted with community members and healthcare workers
Key informant interviews will be conducted with relevant stakeholders
All qualitative sessions will be recorded, transcribed, and analyzed for themes
3.7 Data Analysis
3.7.1 Diagnostic Accuracy Data
The following metrics will be calculated using a 2×2 contingency table in GraphPad Prism:
Sensitivity = (TP/(TP + FN)) * 100
Specificity = (TN/(TN + FP)) * 100
PPV = (TP/(TP + FP)) * 100
NPV = (TN/(TN + FN)) * 100
Accuracy = (TP + TN)/(TP + TN + FP + FN) * 100
Kappa statistic (κ) = (Po - Pe)/(1 - Pe)
McNemar's test will be applied to compare performance between methods
Level of agreement between trained lab scientists and CHEWs will be assessed
rism:
Gold Standard | Foldscope Positive | Foldscope Negative | Total |
Positive (True Cases) | TP (True Positives) | FN (False Negatives) | TP + FN |
Negative (Non-Cases) | FP (False Positives) | TN (True Negatives) | FP + TN |
Total | TP + FP | FN + TN | N (Total Cases) |
● Kappa statistics will be used to determine the level of agreement between the Foldscope and the gold standard diagnostic approach.
● McNemar’s test will be applied to compare the performance of Foldscope versus gold standard microscopy.
Equations:
Sensitivity = (TP/(TP + FN)) * 100
Specificity = (TN/(TN + FP)) * 100
PPV = (TP/(TP + FP)) * 100
NPV = (TN/(TN + FN)) * 100
Accuracy = (TP + TN)/(TP + TN + FP + FN) * 100
κ = (Po - Pe)/(1 - Pe)
Calculations:
1. Sensitivity (True Positive Rate)
Sensitivity = (TP/(TP + FN)) * 100
Measures the proportion of true infections correctly identified by the Foldscope.
2. Specificity (True Negative Rate)
Specificity = (TN/(TN + FP)) * 100
Measures the proportion of uninfected individuals correctly identified as negative.
3. Positive Predictive Value (PPV)
PPV = (TP/(TP + FP)) * 100
Indicates the likelihood that a positive Foldscope result truly represents an infection.
4. Negative Predictive Value (NPV)
NPV = (TN/(TN + FN)) * 100
Indicates the likelihood that a negative Foldscope result truly represents an absence of infection.
5. Diagnostic Accuracy
Accuracy = (TP + TN)/(TP + TN + FP + FN) * 100
Represents the overall proportion of correctly classified cases.
6. Agreement (Kappa Statistic, κ)
κ = (Po - Pe)/(1 - Pe)
Where:
● PoPo = Observed Agreement (proportion of TP and TN combined)
● PePe = Expected Agreement due to chance
7. McNemar’s Test
● Used to compare the Foldscope's performance against the gold standard, testing whether the proportion of false positives and false negatives differs significantly.
All calculations will be performed using GraphPad Prism's Contingency Table and Agreement Analysis tools.
3.7.2 Qualitative Data Analysis
A thematic analysis of qualitative data will be conducted to explore perceived feasibility, acceptability, and barriers to implementing Foldscope-based diagnostics in community settings. Dedoose software will be used to facilitate coding, categorization, and pattern recognition in transcribed focus group discussions (FGDs), key informant interviews (KIIs), and structured interviews with community health extension workers (CHEWs) and other stakeholders. A deductive and inductive coding approach will be applied, incorporating predefined themes (e.g., usability, training needs, perceived accuracy) while allowing for emergent themes identified during coding. Coding reliability will be enhanced through inter-rater agreement, with discrepancies resolved through discussion. Stakeholder perspectives (e.g., CHEWs vs. community members) will be compared to identify variation in diagnostic feasibility and acceptability. Sentiment analysis will be performed to assess overall attitudes toward Foldscope implementation. Findings from FGDs and KIIs will be triangulated with diagnostic accuracy results to explore how perceived usability and feasibility correlate with Foldscope performance metrics. Descriptive statistics (e.g., frequency of themes, coding matrices) will be used to quantify qualitative findings where applicable. This approach will provide a comprehensive understanding of diagnostic implementation challenges and inform future scale-up strategies for community-based schistosomiasis control.
ETHICAL CONSIDERATIONS
Ethical approval is sought from Ogun institutional and ethical review boards. Written informed consent will be secured from all participants (or guardians for minors).Community health worker participants will be informed of the aims of the study, which will entail them answering a set of questions. Written consent will be collected for anybody participating in qualitative data collection, as well. The option to not participate will be fully communicated. For patients participating, the notification will be given that we are examining their urine and that their health information will be kept fully confidential. Written informed consent will be obtained from each respondent and participants will not be coerced in any way. They will be given the choice to participate or not in the study and the free will to withdraw at any time if they so choose with no negative consequences and appropriate clinical care maintained. No names will be written on consent forms or questionnaires by the research team, so respondents can be assured of confidentiality. Image data stored securely on encrypted, password-protected devices with no mention of names.
4.4 Benefits and Risks
Benefits:
Immediate diagnosis and treatment for infected participants
Potential development of improved diagnostic tools for the community
Knowledge generation to benefit schistosomiasis control programs
Risks:
Minimal discomfort during urine sample collection
Potential breach of confidentiality (mitigated by strict data protection protocols)
4.5 Compensation and Incentives
CHEW/clinician participants will receive appropriate compensation upon completion of both the diagnostic and qualitative components
Community participants will not receive direct financial compensation but will benefit from free screening and treatment if infected
Chapter 5: Result Dissemination
5.1 Notification of Results
5.1.1 Individual Results
Individual test results from urine samples will be communicated within hours (estimated 10-20 minutes)
Positive cases will be referred for standard treatment following national guidelines
Participants will receive appropriate counseling about their results
5.1.2 Stakeholder Notification
Meetings with community health workers and local health leaders
Written summaries in local languages and English to enhance accessibility
Reports to relevant health authorities and partner organizations
5.2 Anticipated Products and Impact
Standardized Foldscope diagnostic protocol
Training materials for health workers
Documented themes of feasibility to inform future efforts
Documented themes of community acceptability and barriers
Data for image analysis algorithms for schistosomiasis detection
5.3 Dissemination Plan
Application for National Geographic's level 1 grant for Freshwater Storytelling for a 2026 media project
Peer-reviewed journal submissions with open-access, with credit to all parties involved
Regional and international conference presentations
Reports to relevant Nigerian health authorities
5.4 Timeline
First phase (April 2025):
Establish communication and collaboration with national, state, and local government leadership
Engage community leaders, NTD coordinators, and health workers
Communicate goals and methods
Second phase (July 2025):
Train community health workers in microscopy techniques
Assess diagnostic accuracy vs conventional methods
Gather qualitative data on feasibility and potential improvements
Assess infection etiology education and clinical algorithms
Address usability, training, and logistical challenges
Optimize protocols for image acquisition, interpretation, and reporting
Third phase (August-December 2025):
Data analysis
Manuscript preparation
Dissemination activities
5.5 Data Sharing and Accessibility
De-identified datasets will be shared following ethical guidelines and data privacy regulations
Results will be published in open-access journals to ensure information can be used and scaled up by local or international efforts
6. Bibliography
Akinwale, O. P., Ajayi, M. B., Akande, D. O., Gyang, P. V., Adeleke, M. A., & Dike, A. N. (2010). Urinary schistosomiasis around Oyan Reservoir, Nigeria: twenty years after the first outbreak. Iranian Journal of Public Health, 39(1), 92-95.
Archer, J., Barksby, R., Pennance, T., et al. (2024). Analytical and clinical assessment of a novel, high-sensitivity assay for detection of Schistosoma DNA in human urine samples. Clinical Microbiology and Infection, 30(1), 107-114.
Chatterji, S., Hotez, P. J., & Engels, D. (2024). Female genital schistosomiasis: A neglected tropical gynecologic condition and HIV risk factor. The Lancet Infectious Diseases, 24(1), e12-e18.
Dawaki, S., Al-Mekhlafi, H.M., Ithoi, I., et al. (2015). The menace of schistosomiasis in Nigeria: Knowledge, attitude, and practices regarding schistosomiasis among rural communities in Kano State. PLoS ONE, 10, e0143667.
Ephraim, R. K., Dickson, E. K., Derrick, N. B., & Wiredu, E. K. (2025). Field evaluation of the Foldscope for Schistosoma haematobium diagnosis in rural Ghana: A pilot study. PLoS Neglected Tropical Diseases, 19(1), e0011567.
Ekpo, U. F., Alabi, O. M., Oluwole, A. S., & Sam-Wobo, S. O. (2012). Schistosoma haematobium infections in preschool children from two rural communities in Ijebu East, southwestern Nigeria. Journal of Helminthology, 86(3), 323-328.
Ezeh, C.O., Onyekwelu, K.C., Akinwale, O.P., Shan, L., & Wei, H. (2019). Urinary schistosomiasis in Nigeria: A 50-year review of prevalence, distribution, and disease burden. Parasite, 26, 19.
Faust, C. L., Osakunor, D. N. M., Downs, J. A., et al. (2020). Schistosomiasis control: Leave no age group behind. Trends in Parasitology, 36, 582-591.
Mtethiwa, A. H., Nkwengulila, G., Bakuza, J., et al. (2015). Extent of morbidity associated with schistosomiasis infection in Malawi: A review paper. Infectious Diseases of Poverty, 4, 25.
Sharma, S. K., Mudgal, S. K., Gaur, R., Chaturvedi, J., Rulaniya, S., & Sharma, P. (2024). Navigating sample size estimation for qualitative research. Journal of Medical Evidence, 5(2), 133-139. https://doi.org/10.4103/JME.JME_59_24
Van, G. Y., Onasanya, A., van Engelen, J., Oladepo, O., & Diehl, J. C. (2020). Improving access to diagnostics for schistosomiasis case management in Oyo State, Nigeria: Barriers and opportunities. Diagnostics, 10(5), 328.
Vasileiou, K., Barnett, J., Thorpe, S., et al. (2018). Characterising and justifying sample size sufficiency in interview-based studies: Systematic analysis of qualitative health research over a 15-year period. BMC Medical Research Methodology, 18, 148. https://doi.org/10.1186/s12874-018-0594-7
Xiao, Y., Lu, Y., Hsieh, M., Liao, J., & Wong, P. K. (2016). A microfiltration device for urogenital schistosomiasis diagnostics. PLoS ONE, 11(4), e0154640. https://doi.org/10.1371/journa...
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