Revisiting Immunity Versus Exposure in Schistosomiasis: A Mathematical Modelling Study of Delayed Concomitant Immunity, 1998-2000

Oettle, Rebecca C and Pinot de Moira, Angela and Vennervald, Birgitte J and Dunne, David W and Kabatereine, Narcis B and Wilson, Shona (2024). Revisiting Immunity Versus Exposure in Schistosomiasis: A Mathematical Modelling Study of Delayed Concomitant Immunity, 1998-2000. [Data Collection]. Colchester, Essex: UK Data Service. 10.5255/UKDA-SN-857172

Schistosomiasis remains a major public health problem in many developing countries, Uganda inclusive. It affects the poorest people, living in remote, marginal and rural areas, and causes life-long disability, disfigurement, reduced economic productivity and social stigma. In Hoima District, communities on the shores of Lake Albert retain high infection intensities levels. This is despite concerted efforts to to provide annual community wide preventative chemotherapy through mass drug administration (MDA) programmes, with the latest reported coverage rates for districts with Lake Albert shores being above the WHO target of 75% of those eligible for treatment (currently school aged children and adults). Failure to gain control of infection in primary school children can result in the development of persistent morbidity that can be life threatening in adulthood. Without improved intervention we will fail to meet the Sustainable Development Goal 3 aim of promoting well being for all. The data pertains to a transmission modelling work package within the FibroScHot research programme. The modelling studies update models currently available for schistosomiasis, adapting them to transmission in the Lake Albert region prior to simulating increased treatment frequency in line with the clinical trial at the core of the FibroScHot project.

Data description (abstract)

The relative contributions of acquired immunity and exposure to the distinct epidemiological patterns of human schistosomiasis has been long debated. There is considerable evidence that humans acquire immunity to infection with age, providing partial protection in adulthood. However age- and sex-related contact patterns with water bodies contaminated with infectious cercarial schistosome larvae also contribute to the epidemiological profiles of infection.

The data supported the development a novel schistosome transmission model that incorporates both partially protective immunity represented by immunoglobulin E (IgE) antibody levels specific to Schistosoma mansoni Tegumental-Allergen-Like protein 1 (SmTAL1-IgE), and host age- and sex-dependent patterns of exposure. The model was fitted using a Baysien approach to individual data on exposure to infectious cercariae, infection levels measured as eggs per gramme of faeces (epg) and SmTAL1-IgE levels. The aim was to determine the importance of immunity parameters in optimal Schistosoma mansoni transmission models.

The data is a sub-set of data from a longitudinal re-infection study held by the University of Cambridge Schistosomiasis Research Group. The data was collected between 1998 and 2000 to empirically investigate the relative roles of exposure to the infectious cercarial life stage, and the development of partial immunity, on Schistosoma mansoni re-infection levels measured on a micro-geographical scale. Exposure was derived from longitudinal water contact observations and systematic malacology surveys of the parasites’ intermediate hosts. Infection levels and SmTAL1-IgE were measured pre- and post-treatment with praziquantel. The sub-set of data is for one of the two ethnic groups who originally participated - the members of whom are now the predominant ethnic group in Lake Albert shoreline communities. To be included in the data set an individual record also had to have both a cercarial exposure score and a pre-treatment egg count.

Data creators:

Creator Name	Affiliation	ORCID (as URL)
Oettle Rebecca C	University of Cambridge	https://orcid.org/0000-0002-0502-7355
Pinot de Moira Angela	University of Cambridge	https://orcid.org/0000-0003-3593-8472
Vennervald Birgitte J	University of Copenhagen	https://orcid.org/0000-0001-5721-3494
Dunne David W	University of Cambridge	https://orcid.org/0000-0002-8940-9886
Kabatereine Narcis B	Vector Control Division Uganda Ministry of Health	https://orcid.org/0000-0001-7036-5716
Wilson Shona	University of Cambridge	https://orcid.org/0000-0001-5725-4376

Sponsors:

European and Developing Countries Clinical Trial Partnership 2 Programme

Grant reference:

RIA2017NIM-1842

Topic classification:

Health

Keywords:

TRANSMISSION OF DISEASE, IMMUNE SYSTEM, MATHEMATICAL MODELS

Project title:

"Impact of increased praziquantel frequency on childhood fibrosis in persistent schistosomiasis morbidity hotspots: FibroSchot (WP3 - mathematical models).

Grant holders:

Shona Wilson, Joanne Webster, Martin Walker

Project dates:

From	To
2017	2024

Date published:

11 Jun 2024 09:48

Last modified:

11 Jun 2024 09:48

Coverage and Methodology

Collection period:

Date from:	Date to:
1998	2000

Geographical area:

Booma, Buliisa District

Country:

Uganda

Data collection method:

The age (year) and sex of each individual was recorded at baseline.

Schistosoma mansoni egg counts were collected pre-treatment in 1998. Individuals received two treatments with praziquantel, 2-weeks apart and Schistosoma mansoni egg counts were again collected 5-weeks, 12-months and 18-months post the 2nd treatment. Egg counts are generated from a maximum of 3-stool samples at each timepoint from which two kato-katz slides were prepared.

Plasma samples were collected pre-treatment and 5-weeks post the second praziquantel treatment. The data set contains IgE specific to S. mansoni Tegument Allergen-Like 1 (SmTAL1) protein measured in these plasma samples by ELISA. The data recorded is the optical density from the ELISA.

Extensive water-contact observations conducted, in conjunction with systematic snail surveys, between 1998 and 2000 were used to derive a cercarial exposure score. The details of how the cercarial exposure score was derived can be found in Pinot De Moira A, Fulford AJC, Kabatereine NB, et al. Microgeographical and tribal variations in water contact and Schistosoma mansoni exposure within a Ugandan fishing community. Tropical Medicine & International Health 2007; 12: 724–35.

Observation unit:

Individual

Kind of data:

Numeric

Type of data:

Cohort and longitudinal studies, Historical data

Resource language:

English

Access and Administration

Data sourcing, processing and preparation:

The data is a subset of data from a study conducted in Booma Village, Uganda between 1998 and 2000 held by the Schistosomiasis Research Group, Univeristy of Cambridge. The original data collection was generated from funding from the MRC and the Commission of the European Community's Science and Technology for Development program (INCO-DC contract IC18 CT97-0237 and INCO-DEV contract ICA4-CT-1999-10003). The Principal Investigators of these grants (Profs. David W Dunne and Birgitte J Vennervald) and the Principal Investigator in Uganda (Dr Narcis Kabatereine) are all named authors of this dataset and have provided permission for the data to be shared. The sub-set is representative of one of the two ethnic groups who participated in the orginal study. It is also restricted to those individuals for whom there was both a recorded pre-treatment Schistosoma mansoni egg count and a cercarial exposure score. Age in years, as originally recorded, has been collapsed into 5-year age groups to improve participant anonymity. Post-treatment Schistosoma egg count data are incomplete due to loss to follow-up or no stool sample collected. This missing data points are labelled "not collected." SmTAL1-IgE ODs are incomplete at both baseline and 5-weeks post-treatment as plasma samples were not collected from all individuals at baseline and further individuals were lost to follow-up. These missing data points are labelled "not measured".

Rights owners:

Name	Affiliation	ORCID (as URL)
Kabetereine Narcis B	Vector Control Division Uganda Minnistry of Health	https://orcid.org/0000-0001-7036-5716
Wilson Shona	University of Cambridge	https://orcid.org/0000-0001-5725-4376