In rural Ogun State, Nigeria, a parasite hiding in freshwater snails quietly damages the bladders of children and adults, and it can lead to cancer. With local health workers, scientists, and educators, we’re testing whether $2 microscopes, drone-mapped rivers, and play-based lessons can bring it under control at the last mile.
Schistosomiasis is a parasitic worm infection that hides in freshwater snails and can cause bladder cancer. In the riverside communities of Ogun State, trained local health workers will use $2 microscopes to test and treat people where they live. Drone mapping will find the snail host’s habitat so it can be targeted. And monthly, game-based lessons teach children how the disease spreads and how to stay safe.
We hypothesize that this One Health approach, treating people, animals, and environment together, will lower both how many people are infected and how heavily.
The short version, in three questions.
Schistosomiasis spreads through contact with freshwater that holds infected snails, which is common wherever there’s no clean water supply. The worm silently damages the bladder over years and can lead to bladder cancer. Yet it’s rarely treated, partly because blood in the urine is so common that it’s been normalized locally as “male menstruation.”
The standard test needs lab equipment and a clinic visit. Neither is realistic in last-mile communities. The treatment, praziquantel, is effective, but it hardly reaches the most rural areas. And treating everyone is futile without addressing the water contact that reinfects people.
In 2025, in a study funded by our first crowdfunding campaign, community health workers trained for just a few days reached 90%+ diagnostic accuracy with a $2 Foldscope. That’s the foundation.
But snails and worms don’t disappear because people take medicine, so communities get reinfected again and again. We’re pairing testing with evidence-based environmental protocols pioneered in Senegal, adapted with communities. And because children are the ones playing and swimming in the water, we’re adding lessons that can change behavior in a way pills alone cannot.
One Health is the idea that human, animal, and environmental health are inextricably linked. Schistosomiasis is a textbook case: the parasite cycles between people, snails, and water. It’s the namesake of the project (Schistosomiasis Control from a One Health Perspective), and it’s why SCOPE works on diagnosis, ecology, and education at once.
Schistosomiasis, known locally in southwestern Nigeria as Àtọ̀sí Ajá, is caused by a parasitic worm that lives in fresh water. Its reservoir is several species of freshwater snail, which become infected when urine from infected people reaches local waterways. Inside the snail, the parasites mature and are released as cercariae, which burrow into the skin of anyone who wades, washes, fishes, or swims.
It infects tens of millions of people across rural sub-Saharan Africa, and hits school-aged children hardest. Left untreated for years, a curable infection turned chronic can lead to bladder cancer, infertility, and lasting damage to the reproductive tract that makes HIV easier to contract.
Treating the people who are infected is essential. But unless we address what drives transmission, the same people will be infected again next year. So SCOPE works on three fronts at once.
01 Community health workers use a $2 Foldscope and our reusable SchistoFilter to test urine where people live — and treat those who test positive with praziquantel on the spot, instead of waiting for mass drug campaigns.
02 Drone imagery of water-access points, checked by hand on the ground, maps where the snail host actually lives, so communities can choose real interventions, like clearing trash or invasive plants, instead of guessing. Environmental DNA sampling looks for the parasite in the water itself.
03 Monthly, play-based lessons in Yoruba help school-aged children understand how the parasite spreads and recognize its symptoms. The aim is to shift water contact and encourage treatment-seeking over time. They’re led by Dr. Cynthia Umunnakwe, co-designer of Schisto & Ladders and Hidden Worlds.
The diagnostic half of SCOPE runs on two pieces of frugal science: the Foldscope, a folding paper microscope co-invented by our mentor Manu Prakash, and the SchistoFilter, a reusable filter card we designed around the constraints of rural clinics. No electricity. No lab. A phone camera for a second opinion.
| Measure | SchistoFilter | Standard filter |
|---|---|---|
| Answer in | 2–3 minutes | 10–15 minutes |
| Cost per test | $0.04, reusable | $1.25, single-use |
| Foldscope-ready | Loads directly | Needs extra glass |
Open source: buildable anywhere with local materials, glue, and a razor blade. Early lab validation: 100% sensitivity so far, down to one egg per 10 mL of urine.
In July 2025 we screened 418 people across five communities near the Oyan River Dam. Every sample was read twice: once by community health extension workers using the toolkit, and once by laboratory technicians with standard microscopy.
In eight days, the health workers, most of whom had never used a microscope, went from coin-flip accuracy to strong agreement with the lab. In lab scientists’ hands, the $2 Foldscope performed like a conventional microscope.
| Measure | First community | Final community |
|---|---|---|
| Accuracy | 52.5% | 92.1% |
| Specificity | 53.6% | 96.3% |
Instead of splitting communities into “treated” and “untreated” for good, a stepped-wedge trial rolls SCOPE out in steps. Every community eventually gets test-and-treat, lessons, and habitat mapping — but staggered starts let us compare each community with itself, before and after.
We identified six moderately endemic communities (11–37% prevalence) during fieldwork in August 2026, grouped into three clusters.
| Cluster | Sep–Nov 2026 | Dec 2026–Jan 2027 | Feb 2027 onward |
|---|---|---|---|
| Cluster AStarts September 2026 | SCOPE begins | SCOPE continues | SCOPE continues |
| Cluster BStarts December 2026 | Usual care | SCOPE begins | SCOPE continues |
| Cluster CStarts February 2027 | Usual care | Usual care | SCOPE begins |
Prevalence and intensity (eggs per 10 mL of urine), with a midpoint assessment in December 2026.
Knowledge, attitudes, and practices interviews with children, repeated over time.
Snail counts, habitat mapping, drone imagery, and eDNA across wet and dry seasons.
Novices find parasite eggs through a Foldscope with 79% accuracy.
Read the field note →33 backers fund the first study; ethics approval clears in Ogun State.
Read the field note →418 people screened across five communities; health workers reach 92% accuracy.
Read the field note →Full committee approval from the Ogun State Health Research Ethics Committee.
Read the field note →Communities identified, games piloted, waterways mapped, eDNA sampled, 181 quadrats searched.
Read the field note →Praziquantel moves to local Primary Health Centers.
Environmental samples, in preservative buffer, head to the U.S. for PCR analysis.
300 doses reach the first community; first monthly education visit.
Read the field note →Fuel and supplies for the local team. This is exactly what donations cover.
Help cover it →Finalize snail-habitat risk mapping from August fieldwork.
First education visit for Cluster B; midpoint prevalence assessments across SCOPE communities.
eDNA, drone mapping, and snail counts in the dry season.
First monthly education visit for Cluster C.
I am really excited about this project. The project will help in supporting the fight against a disease of poverty that affect the poorest and most marginalized people in African countries.
I am excited about this project, primarily because it aims to address some critical operational gaps in the global fight towards eliminating schistosomiasis. I am super-intrigued by the team composition as well.
I know the team leader of this project and have discussed this research with the team. This is solid science that explorers a very new and relevant topic of medical science!
SCOPE is led on the ground by Nigerian scientists, health officials, and community health workers, alongside the student-led Health in Your Hands team.
Manu PrakashFoldscope co-inventor · research mentor · Prakash Lab, Stanford
Giulio De LeoDisease ecologist · Stanford
William McCarthyChief Executive Officer
Caroline CrainChief Scientific Officer
Simon BirkPresident · COO
Cristina SalasEcology fieldwork
Jon BeaubrunEngineering
Megan NgaiEducation design
Richa JohnEducation design
Thomas CopelandPhotography
Read the note A SCOPE field note from August’s snail survey: why we look for snails at all, what a Stanford lab found when snails met biofouled plastic, how we sampled 181 random quadrats without cherry-picking, and what trash does (and doesn’t) tell us about where the parasite lives.
Read the note Back from Nigeria, Caroline takes the SchistoFilter into formal validation: 100% sensitivity so far, a limit of detection of one egg per 10 mL, and answers in 2–3 minutes instead of 10–15.
Read the note How do you teach a life cycle no one can see? An education note from Imoto: the Hidden Worlds puzzle, what 191 children knew at baseline, and a pop quiz that ended in butterflies.
Read the note Praziquantel reaches the first community in SCOPE’s test-and-treat trial: what the drug does, why it rarely makes the trip, and how community health workers will test, treat, and track.
Read the note The Ogun State Health Research Ethics Committee approved SCOPE after full committee review. Here’s what the approval requires, and the consent, supervision, and community-permission practices behind it.
Read the note A SCOPE essay from the Oyan River communities: a van with a punctured gas tank, a community health worker with a bar of soap, and what six days of Foldscope diagnostics taught the team about where innovation actually lives.
We’re a student-led nonprofit with a lean budget, patched together from medical-school grants, global-health reimbursements, and individual gifts. Every line below covers bare-minimum operating costs for work already under way.
Getting community health workers between remote riverside communities, and the team to drone-survey sites at water-access points — where car access is no easy feat.
Staff time at our Nigerian partners (the Ministry of Health NTD office, FMC Abeokuta, and FUNAAB) for community entry, ethics compliance, and coordinating praziquantel distribution.
Urine testing, materials for health lessons, and drone surveys: the core tools behind rural treatment and snail-habitat mapping.
100% of every dollar goes to program budgets. We’re all-volunteer, so none of it goes to overhead.
DonatePraziquantel works, and mass drug administration is an important tool. But it hardly reaches the most rural communities (in 2025, 60% of the people we screened had never been treated), and people are reinfected as soon as they touch the same water. Testing close to home finds who needs treatment now; mapping snails and teaching children goes after reinfection.
A folding paper microscope co-invented by our mentor Manu Prakash at Stanford. It costs about $2, needs no electricity, magnifies about 340×, and couples to a phone camera so images can be shared and double-checked.
The parasite spends part of its life inside freshwater snails, so finding their habitat lets communities decide what to remove. Snail control is a WHO-endorsed strategy in moderately endemic areas. In August we found snails more often where trash collected — likely a marker of the calm, heavily used water snails love. Read the field note.
Nigerian scientists, health officials, and community health workers, together with the student-led Health in Your Hands team, mentored by Manu Prakash and disease ecologists at Stanford’s Center for Human & Planetary Health. Meet the collaborators.
Yes. SCOPE has full approval from the Ogun State Health Research Ethics Committee, follows WHO guidelines for diagnosis and treatment, and runs on informed consent and community permission. How we work.
Share this page, follow along in our field notes, or get in touch if you’d like to collaborate — especially if you have ideas for measuring biofilm in the field on a shoestring budget.
Snails and worms don’t disappear because people take medicine, and this work doesn’t happen without you. Fund the fieldwork, share the story, or join us.
