Plain English Summary
Background and study aims
Schistosomiasis is an infection caused by a parasitic worm that lives in fresh water in tropical and subtropical areas. The parasite can infect both humans and fresh water snails. In Côte d’Ivoire, schistosomiasis is endemic (regularly found) and the national control strategy emphasizes preventive chemotherapy (medication). However, this strategy does not protect patients from being infected again and so additional control measures are needed. The aim of this study is to explore the association between the snails that carry schistosomiasis, freshwater prawns that might act as their natural predators, and schistosomiasis among school-aged children and adults.
Who can participate?
Children aged 9–12 and adults aged 20–55 who live in participating villages in Côte d’Ivoire
What does the study involve?
All human-water contact points are visited four times over a 14-month period once every season in each of the 24 villages, in order to collect samples of snails and prawns. Participants give stool and urine samples which are checked for schistosomiasis parasite eggs.
What are the possible benefits and risks of participating?
Participants who are found to be infected are treated with the drug praziquantel. Villages where the prevalence of schistosomiasis is over 20% are all treated with praziquantel by the national schistosomiasis control programme. Praziquantel has few adverse events (e.g. mild abdominal pain and headache).
Where is the study run from?
1. Swiss Tropical and Public Health Institute (Switzerland)
2. Université Félix Houphouët-Boigny (Côte d’Ivoire)
When is the study starting and how long is it expected to run for?
May 2015 to December 2016
Who is funding the study?
The Bill & Melinda Gates Foundation through the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) based at the University of Georgia
Who is the main contact?
Prof. Juerg Utzinger
Trial website
Contact information
Type
Scientific
Primary contact
Prof Jürg Utzinger
ORCID ID
http://orcid.org/0000-0001-6885-0798
Contact details
Socinstrasse 57
Basel
4002
Switzerland
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
N/A
Study information
Scientific title
Relationship between native riverine prawns, intermediate host snails and schistosomiasis prevalence in two river systems in Côte d’Ivoire
Acronym
Study hypothesis
Native riverine prawns (Macrobrachium) act as natural predators of schistosomiasis intermediate host snails (Bulinus sp and Biomphalaria), and hence influence the transmission of schistosomiasis.
Ethics approval
Comité National d’Éthique et de la Recherche, Ministère de la Santé et de Lutte contre le SIDA, 22/01/2015, ref: 114/MSLS/CNER-dkn
Study design
Ecological study, including a single cross-sectional parasitological survey in humans and four cross-sectional surveys pertaining to prawns and snails
Primary study design
Observational
Secondary study design
Ecological study
Trial setting
Other
Trial type
Other
Patient information sheet
Not available in web format, please use the contact details to request a patient information sheet
Condition
Schistosoma mansoni infection, Schistosoma haematobium infection
Intervention
Twenty-four villages located in two hydrological systems of Côte d’Ivoire will be the selected for the current study. The villages will be situated within a 3 km radius from the main river in the two hydrological system. The villages will be separated from each other by at least 5 km. All human-water contact points will be visited four times over a 14 months study period, once every season in each of the 24 localities. Intermediate host snails will be sampled by two experienced malacologists during 15 min using kitchen sieves and forceps. Prawns will be collected using an electric fishing device. A total of 150 individuals (100 pupils aged 9–12 years and 50 adults aged 20–55 years) will be invited to give stool and urine samples during a single cross sectional survey. Stool samples will be subjected to duplicate Kato-Katz thick smear, and slides quantitatively examined under microscope for Schistosoma mansoni eggs and urine filtration method for to determine Schistosoma haematobium eggs.
Intervention type
Other
Phase
Drug names
Primary outcome measure
Schistosoma mansoni and S. haematobium infection status, assessed with the Kato-Katz and urine filtration methods, respectively, in a cross-sectional survey conducted from 21/01/2016 to 29/01/2016
Secondary outcome measures
1. The presence and number of riverine prawns, collected using an electric fishing device, determined in four surveys once every season:
01/10/2015-12/10/2015
07/04/2016-19/04/2016
19/07/2016-31/07/2016
04/12/2016-15/12/2016
2. The presence and number of intermediate host snails, sampled using kitchen sieves and forceps, determined in four surveys once every season:
01/10/2015-12/10/2015
07/04/2016-19/04/2016
19/07/2016-31/07/2016
04/12/2016-15/12/2016
Overall trial start date
28/05/2015
Overall trial end date
15/12/2016
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
1. Written informed consent signed by adults (aged 20-55 years) and parents/guardian of children (aged 9-12 years) and oral assent by children
2. Able and willing to provide a single urine sample at the baseline cross-sectional survey
3. No known allergy to study medication (i.e. praziquantel)
Participant type
Mixed
Age group
Mixed
Gender
Both
Target number of participants
3600
Participant exclusion criteria
1. No written informed consent by adults and parents/guardian on behalf of their children
2. Recent use of anthelminthic drug (within past 4 weeks)
Recruitment start date
21/01/2016
Recruitment end date
29/01/2016
Locations
Countries of recruitment
Cote d'Ivoire
Trial participating centre
Swiss Tropical and Public Health Institute
Socinstrasse 57
Basel
4051
Switzerland
Trial participating centre
Université Félix Houphouët-Boigny
Unité de Formation et de Recherche Biosciences
22 BP 770
Abidjan
22
Cote d'Ivoire
Sponsor information
Organisation
Swiss Tropical and Public Health Institute
Sponsor details
Socinstrasse 57
Basel
4051
Switzerland
Sponsor type
Research organisation
Website
Funders
Funder type
Charity
Funder name
The Bill & Melinda Gates Foundation through the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) based at the University of Georgia (sub-awards no. RR374-053/4787986)
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
The study protocol has not yet been published but will be submitted to BMC Public Health and available online in the next few months. The trialists intend to publish the study results in the peer-reviewed (whenever possible open-access) literature before the end of 2018.
IPD sharing statement
The data sharing plans for the current study are unknown and will be made available at a later date.
Intention to publish date
31/12/2018
Participant level data
To be made available at a later date
Basic results (scientific)
Publication list