https://orcid.org/0000-0002-9214-6095
Figures
Abstract
Background
Schistosomiasis (SCH) and Soil-transmitted helminthiasis (STH) remain major neglected tropical diseases across sub-Saharan Africa. In Akwa Ibom State, preventive chemotherapy (PC) has been implemented in endemic Local Government Areas (LGAs). This study assessed the impact of five effective rounds of PC on the prevalence and intensity of SCH and STH in 26 endemic LGAs.
Methods
This study was carried out in 26 LGAs of Akwa Ibom State between September and October 2025. A school-based cross-sectional survey was employed. Schools were purposefully selected from endemic wards, and a total of 200–300 samples were collected per LGA from school children of both sexes aged 8–14 years. Samples were collected using a systematic random sampling method. Questionnaires were administered using electronic data forms. Stool samples collected were analyzed using the Kato-Katz technique, while urine samples were analyzed using the urine filtration method. Conventional microscopy alongside a novel AiDx digital microscope was used to examine prepared specimen. Data obtained were analyzed using descriptive statistics, chi-square test, bivariate and multivariate logistic regression on SPSS, and maps were generated using ArcMap.
Results
No cases of Schistosoma mansoni or Schistosoma haematobium were detected across the 26 LGAs (0.0% prevalence). The overall prevalence of STH was 27.62% (95% CI: 26.54–28.72), ranging from 4.92% to 71.65% across LGAs. Species-specific prevalence was 15.38% (95% CI: 14.52–16.28, range: 3.3% to 38.3%) for hookworm, 15.10% (95% CI: 14.24–15.99, range: 1.6% to 67.0%) for Ascaris lumbricoides, and 1.52% (95% CI: 1.25–1.85, range: 0.4% to 9.3%) for Trichuris trichiura. Mbo (71.65%) and Udong Uko (62.04%) recorded the highest prevalences, whereas Ika (4.92%) had the lowest. Prevalence was significantly higher among children aged 11–14 years (31.77%; 95% CI: 29.95–33.64) compared with those aged 8–10 years (95% CI: 23.77–26.46), and among males (29.30%; 95% CI: 27.80–30.86) compared with females (25.73%; 95% CI: 24.24–27.35) (p < 0.05). 98.66%, 99.09% and 100.0% of schoolchildren had light infections of A. lumbricoides, hookworms and T. trichiura respectively. Compared with baseline data, STH prevalence declined by 30.15%. Significant risk factors associated with STH include; males (aOR = 1.196, 95% CI: 1.072 – 1.335), age group of 11–14 years (aOR = 1.391, 95% C.I.: 1.244 – 1.554), dry pit latrine (aOR = 1.464, 95% C.I. = 1.239 – 1.731), schools where children urinate (aOR = 2.620, 95% C.I.: 2.362 – 2.929) and defecate (aOR = 1.238, 95% C.I. = 1.097 – 1.396) around school or wait to defecate after school (aOR = 1.830, 95% C.I. = 1.365 – 2.454), schoolchildren that drinks from surface water (aOR = 1.731, 95% C.I. = 1.486 – 2.017) or boreholes that uses hand pump (aOR = 1.666, 95% C.I. = 1.412 – 1.965).
Conclusion
Schistosomiasis was not reported in 26 LGAs of Akwa Ibom. Soil-transmitted helminths had a significant reduction in prevalence, but with varying prevalence across the states. There is a need for sustained preventive chemotherapy against STH in the State. Improvement in water, sanitation, and hygiene (WASH) infrastructures to create behavioural change, and strengthen the control efforts.
Author summary
This study assessed the impact of 5 rounds of mass drug administration (MDA) on schistosomiasis and soil-transmitted helminthiasis (STH) among 6,431 school-aged children. In this current study, no cases of schistosomiasis were detected in school children in 26 LGAs. STH prevalence dropped by 30.15% to 27.62%, but disparities persist across regions (4.92% to 71.65%). Hookworm and Ascaris lumbricoides are the main STH species. Risk factors for STH include age 11–14 years, male, poor sanitation and inadequate toilet facilities. The MDA effort succeeded in eliminating schistosomiasis, but sustained interventions are required for STH, along with improved WASH infrastructures and behavioural changes to meet the WHO 2030 targets.
Citation: Opara KN, Yaro CA, Ikpeida NW, Mohammed A, Marcus HJ, Azu K, et al. (2026) Impact assessment of effective rounds of mass drug administration against schistosomiasis and soil transmitted helminthiasis among school age children in Akwa Ibom State, Nigeria. PLoS Negl Trop Dis 20(8): e0014603. https://doi.org/10.1371/journal.pntd.0014603
Editor: Peter U. Fischer, Washington University School of Medicine, UNITED STATES OF AMERICA
Received: March 14, 2026; Accepted: July 21, 2026; Published: August 7, 2026
Copyright: © 2026 Opara et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All the datasets used and analyzed during the current study have been attached as supporting information.
Funding: The author(s) received no specific funding for this work.
Competing interests: The authors have declared that no competing interests exist.
1 Introduction
Schistosomiasis (SCH) and soil-transmitted helminthiasis (STH) are among the most prevalent neglected tropical diseases (NTDs), disproportionately affecting impoverished communities in sub-Saharan Africa [1,2]. SCH, caused by Schistosoma species (primarily S. haematobium in Nigeria), leads to urinary tract damage, haematuria, anaemia, and increased HIV susceptibility, with over 240 million global cases [3]. STH, including Ascaris lumbricoides, Trichuris trichiura, and hookworms, causes malnutrition, growth stunting, and cognitive impairment, infecting 1.5 billion people worldwide [4].
In terms of burden, Nigeria has been at the forefront of the African region, with 134 million people at risk of SCH and widespread STH transmission [5]. The WHO NTD Roadmap 2021–2030 targets both diseases for elimination as a public health problem (EPHP) for SCH (<1% prevalence in School-Age Children (SAC)) and STH (<2% moderate/heavy intensity) by 2030, with impact assessments to be done after 3–5 MDA rounds [6].
Prior to the impact assessment, the preventive chemotherapy (PC) strategy implemented in Akwa Ibom State was led by the Federal Ministry of Health (FMoH) in collaboration with the State Ministry of Health and supported by Helen Keller Intl focused on large scale Mass Administration of Medicines (MAM) targeting school-aged children (SAC) aged 5–14 years. For STH, the strategy mandated biannual PC in areas with prevalence above 50%, and annual PC in regions with a 20% to 49.9% prevalence with over 75% coverage across implementation units (IUs) using albendazole or menbendazole, while SCH control among SAC relied on a case-management approach utilizing praziquantel [7]. Earlier baseline studies in Akwa Ibom State covered all the 31 LGAs. The baseline surveys (2013–2015) in Akwa Ibom State revealed a high level of STH endemicity (25.1 - 91.4%), and a low level of SCH prevalence (0.0 - 1.2%) [8,9]. In 2024, an impact assessment survey was carried out in five (5) LGAs that has achieved five effective rounds of mass drug administration (MDA). The current assessment targets the remaining 26 LGAs that have similarly completed five effective treatment rounds, with the aim of evaluating the impact of the intervention and informing decisions on the next phase of the elimination programme.
This study evaluates the impact of PC on the prevalence, intensity and endemicity of SCH and STH across 26 LGAs of Akwa Ibom State. The assessment follows five effective rounds of PC and is designed to determine whether the elimination as a public health problem (EPHP) targets have been achieved in accordance with the WHO monitoring and evaluation framework [7]. The survey is part of the national and state NTD strategic plan to provide data needed for planning, implementation, and monitoring the progress of the SCH and STH control programme in Akwa Ibom State.
2 Methods
2.1 Ethical considerations
The Akwa Ibom State Research Ethics Committee provided ethical approval (AKHREC/08/09/25/376). Community gatekeepers were provided with administrative clearance and letters of introduction. Parents or guardians of participating school-aged children (SAC) provided written informed consent and assent of children was obtained where necessary. It was voluntary and confidential.
2.2 Study site
Akwa Ibom State is situated in the south-south region of Nigeria. Its location is between latitudes 4°32’1’’ and 5°33’1’’ North and longitudes 7°25’1’’ and 8°25’1’’ East. The state shares its borders with Rivers State on the East side, Cross River on the West, Abia State on the North and the Gulf of Guinea on the South. The study was conducted across 26 selected LGAs of Akwa Ibom State. These LGAs includes; Abak, Eket, Essien Udim, Etim Ekpo, Etinan, Ibesikpo Asutan, Ibiono Ibom, Ika, Ikono, Ikot Ekpene, Ini, Itu, Mbo, Mkpat Enin, Nsit Atai, Nsit-Ibom, Nsit Ubium, Obot Akara, Okobo, Oron, Oruk Anam, Udung Uko, Ukanafun, Uruan, Urue-Offiong/Oruko and Uyo (Fig 1).
This figure was created by the authors on ArcMap 10.8 software. Available at https://desktop.arcgis.com/en/arcmap/index.html. The Nigeria and Akwa Ibom State shapefile was obtained from https://data.humdata.org/dataset/geoboundaries-admin-boundaries-for-nigeria, a publicly accessible database and are licensed under CC BY 4.0 (https://data.humdata.org). The authors allow unrestricted reuse of this map provided that proper credit is given to the source.
2.3 Community sensitization/mobilization
The community mobilization was done by advocacy visits, local media and working with school authorities and community leaders. The research objectives, methods and voluntary nature of the study were clearly explained before the data collection.
2.4 Study design
A cross-sectional impact assessment among school-aged children was undertaken in October 2025 after the implementation of 5–8 effective rounds of mass drug administration (MDA). The study employed a two-stage sampling design aligned with the WHO [7] guidelines for impact assessment. Initially, five (5) wards were purposively selected from each Local Government Area (LGA), taking into account their epidemiological importance and baseline endemicity profiles identified during the baseline survey.
2.4.1 Selection of primary sampling units (PSUs).
In each implementation unit (IU), the school with the highest prevalence of STH and SCH was purposively selected as the primary sampling unit (PSU). The selection was made from the list of eligible schools within the IU resulting in a total of five schools per LGA and 130 PSUs in 26 LGAs.
2.4.2 Selection of participants.
A systematic sampling method was used to randomly select 52 SAC aged 8 years to 14 years (26 males and 26 females) in every PSU [7,10]. In cases that the enrolment was more than the target numbers, random starting point and sample interval were used. In accordance with this criterion the total sample size of over 7,000 was aimed to be reached. There were however 6,431 valid samples that were analysed.
2.5 Sample collection
School-aged children were grouped in terms of gender and age by a systematic random sampling procedure. Sampling intervals were applied in the situations where the enrolment was larger than the required (e.g., SI = total SAC/required; every nth child sampled at a random starting point). All chosen children gave stool sample (Collected in labelled containers) and urine sample collected mid-morning (10:00–14:00 hours) so as to maximise the detection of Schistosoma haematobium egg excretion.
2.6 Laboratory examination of samples
Samples collected were transported to the laboratory for processing and examination. Parasite eggs in stools were analysed with the use of the Kato-Katz method on STH (Ascaris lumbricoides, Trichuris trichiura, and hookworm) and intestinal schistosome (Schistosoma mansoni) [1,11]. Hookworm slides were read in less than 60 minutes to avoid the clearance of eggs. The counts of eggs were converted in terms of eggs per gram (epg) and categorized based on WHO intensity thresholds. Urine was screened for haematuria using Combi-9 reagent strips, followed by filtration using filtration kits, and thereafter microscopy for S. haematobium eggs. Conventional microscope was used to examine prepared slides.
For quality control, 10% of slides were re-read by a senior parasitologist and blinded duplicate Kato-Katz was carried out on 20% of samples [12]. The AiDx NTDx device, a digital microscope with performance accuracy of 95% was used alongside conventional microscope to increase quality control during sample examination [13,14]. Intensity was classified according to WHO standards.
2.7 Electronic data collection
The electronic data collection was done using the KoboCollect App on Android based devices linked to a cloud server. The results of school-level, participant-level, stool, and urine were recorded in four structured forms. The GPS coordinates of every PSU were noted. Data validation and backup procedures were monitored on a regular basis. Proper monitoring of the transmitted data was done during the study. Hardcopy backups were also maintained.
2.8 Data Analyses
Cleaning of data was done in Microsoft Excel. The prevalence between the categories of infection, i.e., based on sex, age groups, and LGAs were determined through descriptive statistics. WHO thresholds were used to classify endemicity; STH(< 2%, ≥ 2% to < 10%, ≥ 10% to < 20%, and ≥ 20%) and SCH (<10%, ≥ 10% to 49.9, and ≥ 50%) (WHO, 2024). The severity of the infections was determined based on WHO guidelines [7]. The 95% confidence intervals (CI) were used to calculate prevalence estimates. Chi-square (χ2) analysis was performed to test associations. Bivariate and multivariate logistic regression was used to estimate odds ratios (ORs) and adjusted odds ratios (aORs) with 95% CI. The significant level was established at p < 0.05. Statistical analysis was conducted using Statistical Package for Social Sciences (SPSS) version 27.
3 Results
3.1 Participant characteristics
A total of 6,431 SAC were examined (52.7% males; 47.3% females). The majority (62.2%) were aged 8–10 years, while 37.8% were aged 11–14 years (Table 1).
3.2 Prevalence of SCH and STH infection in 26 LGAs of the state
A total of 6431 students participated in this survey, comprising of 52.7% males (3392 individuals) and 47.3% females (3039 individuals), with 62.2% (3998 individuals) in the age group of 8–10 years and 37.8% (2433 individuals) in the age group of 11–14 years.
In this survey, samples from all SAC revealed they were not infected with Schistosoma mansoni and Schistosoma haematobium, 0.0% prevalence was recorded in all the PSUs across the 26 LGAs studied (Table 2). An overall prevalence of 27.62% [95% C.I. = 26.54 – 28.72%] (1776 students) was recorded among SAC for STH in this survey, with parasite-specific prevalence of 15.38% [95% C.I. = 14.52 – 16.28%] for hookworms, 15.10% [95% C.I. = 14.24 – 15.99%] for Ascaris lumbricoides, and 1.52% [95% C.I. = 1.25 – 1.85%] for Trichuris trichiura. Co-infection was highest between Ascaris lumbricoides and hookworm (3.39%), and least between Trichuris trichiura and hookworm (0.47%) (Table 2).
The result of STH prevalence by LGA is presented in the Table 3. Mbo (71.65%) had the highest prevalence, followed by Udung Uko (62.04%), and the least prevalence was recorded at Ika LGA (4.92%). Comparison of the prevalence among the LGAs was statistically significant (p < 0.05%) (Fig 2, Table 3). Ascaris lumbricoides infection was highest at Mbo LGA (67.0%, 175 children), followed by Udung Uko LGA (57.7%, 158 children) and Okobo (40.8%, 91 children), while the lowest prevalence was at Ika LGA (1.6%, 4 children). Prevalence of Ascaris lumbricoides was statistically significant (p < 0.001) across the LGAs (Table 4, Fig 3). Trichuris trichiura prevalence was highest at Uruan LGA (9.3%, 23 children), followed by Mbo LGA (9.2%, 24 children). Prevalence was also statistically significant across the LGA (p < 0.001) (Table 4, Fig 4). Hookworms infection was highest at Ini LGA (38.3%, 103 children), followed by Nsit Ubium LGA (30.8%, 76 children), while the lowest prevalence was recorded at Ika LGA (3.3%, 8 children), the variation in prevalence was statistically significant across the LGAs (p < 0.001) (Table 4, Fig 5).
This figure was created by the authors on ArcMap 10.8 software. Available at https://desktop.arcgis.com/en/arcmap/index.html. The Nigeria and Akwa Ibom State shapefile was obtained from https://data.humdata.org/dataset/geoboundaries-admin-boundaries-for-nigeria, a publicly accessible database and are licensed under CC BY 4.0 (https://data.humdata.org). The authors allow unrestricted reuse of this map provided that proper credit is given to the source.
This figure was created by the authors on ArcMap 10.8 software. Available at https://desktop.arcgis.com/en/arcmap/index.html. The Nigeria and Akwa Ibom State shapefile was obtained from https://data.humdata.org/dataset/geoboundaries-admin-boundaries-for-nigeria, a publicly accessible database and are licensed under CC BY 4.0 (https://data.humdata.org). The authors allow unrestricted reuse of this map provided that proper credit is given to the source.
This figure was created by the authors on ArcMap 10.8 software. Available at https://desktop.arcgis.com/en/arcmap/index.html. The Nigeria and Akwa Ibom State shapefile was obtained from https://data.humdata.org/dataset/geoboundaries-admin-boundaries-for-nigeria, a publicly accessible database and are licensed under CC BY 4.0 (https://data.humdata.org). The authors allow unrestricted reuse of this map provided that proper credit is given to the source.
This figure was created by the authors on ArcMap 10.8 software. Available at https://desktop.arcgis.com/en/arcmap/index.html. The Nigeria and Akwa Ibom State shapefile was obtained from https://data.humdata.org/dataset/geoboundaries-admin-boundaries-for-nigeria, a publicly accessible database and are licensed under CC BY 4.0 (https://data.humdata.org). The authors allow unrestricted reuse of this map provided that proper credit is given to the source.
Age specific prevalence revealed that school children in the age group of 11–14 years, 31.77% [95% C.I. = 29.95 – 33.64%] had higher prevalence than those in the age group of 8–10 years [95% C.I. = 23.77 – 26.46%] (Table 5). Comparison between the age groups was statistically significant (p < 0.05). Sex specific prevalence revealed a higher prevalence in males [29.30%, 95% C.I = 27.80 – 30.86%] than in females [25.73%, 95% C.I. = 24.24 – 27.35%], comparison of prevalence between sexes was statistically significant (p < 0.05) (Table 5).
3.3 STH infection load estimation
A total of 98.66% (958 school children) and 1.44% (13 school children) had light and moderate infection of A. lumbricoides respectively, had light infection, while 1.44% (14 individuals) had moderate infection. Also, 99.09% (980 school children) and 0.91% (9 school children) had light and moderate infections of hookworms. All 98 school children infected with T. trichiura had light infection. High intensity infection was not recorded across the 26 LGAs (Table 6).
3.4 Comparison between baseline and current prevalence of STH in Akwa Ibom State
An overall prevalence of 27.62% was recorded in the current survey of October 2025, with prevalence (ranges: 4.92% to 71.65%) compared to baseline prevalence of 57.77% (range: 25.1% to 91.39%) for Akwa Ibom State, with a 30.15% reduction in prevalence. Across the 26 LGAs surveyed, there was a reduction in prevalence compared to the baseline. Although some LGAs recorded a significant reduction than others, Abak LGA reported the highest significant reduction in prevalence with over 56.54% reduction (15.66% current, 72.2% baseline), followed by Itu LGA with 43.25% reduction (16.22% current, 59.47% baseline), while Mbo LGA has the least reduction in prevalence with 11.1% reduction (71.65% current, 82.75% baseline) (Fig 6, Table 7).
3.5 Risk factors of STH and infection status
The study also examined the socio-demographic characteristics and WASH factors in relation to the infection status. The risk of acquiring STH infections was significantly associated with sex, age group of school children, type of toilet facility, when and where children urinate and defecate in schools (Table 8). Male school children had a higher likelihood of being infected with STH (aOR = 1.196, 95% CI: 1.072 – 1.335). Children in the age group of 11–14 years (aOR = 1.391, 95% C.I.: 1.244 – 1.554) are at higher risk of being infected with STH. School children that uses dry pit (aOR = 1.464, 95% C.I. = 1.239 – 1.731), urinate around school (aOR = 2.620, 95% C.I.: 2.362 – 2.929), defecate around school (aOR = 1.238, 95% C.I. = 1.097 – 1.396) or wait to defecate after school (aOR = 1.830, 95% C.I. = 1.365 – 2.454) had higher likelihood of being infected with STH. Also, school children that drink water from borehole with hand pump (aOR = 1.666, 95% C.I. = 1.412 – 1.965) and those that drink from surface water (aOR = 1.731, 95% C.I. = 1.486 – 2.017) had higher likelihood of being infected with STH (Table 8).
3.6 Programmatic interpretation of results
The results of this impact assessment has shown significant decrease in the STH prevalence thresholds across the 26 LGAs of Akwa Ibom State. Out of 17 LGAs in the threshold of ≥50% at baseline, 14 remained in the threshold of ≥20% while 3 LGAs moved down to the threshold of ≥10 to <20%. Also, 9 LGAs in the threshold of 20 to 49.9% at baseline, 1 LGA moved down to the threshold of ≥2 to <10%, 7 LGAs moved down to the threshold of ≥10 to <20% while 1 LGA remained in the threshold of ≥20%. Based on this report, 1 LGA requires MDA once in 2 years for a period of 5 years with sustained surveillance activities, 10 LGAs requires MDA once yearly for a period of 5 years with sustained surveillance while 15 LGAs requires MDA twice yearly for a period of 5 years with sustained surveillance activities (Table 9, Fig 7).
This figure was created by the authors on ArcMap 10.8 software. Available at https://desktop.arcgis.com/en/arcmap/index.html. The Nigeria and Akwa Ibom State shapefile was obtained from https://data.humdata.org/dataset/geoboundaries-admin-boundaries-for-nigeria, a publicly accessible database and are licensed under CC BY 4.0 (https://data.humdata.org). The authors allow unrestricted reuse of this map provided that proper credit is given to the source.
4 Discussion
The WHO targeted the elimination of schistosomiasis and soil-transmitted helminthiasis by 2030. In view of this, states that have conducted several rounds of chemotherapy need to assess the status of these diseases through conducting impact assessments to review the control strategies. In 2024, impact assessment was conducted in 5 LGAs co-endemic for STH and SCH following a minimum of five effective rounds of mass drug administration.
The current impact assessment was carried in October 2025, to understand the current distribution of schistosomiasis and soil-transmitted helminthiasis across 26 LGAs. The observation from the current survey carried out in 26 LGAs of Akwa Ibom State revealed 0.0% prevalence of Schistosoma spp. and 27.62% overall prevalence of STH, indicating a 30.15% significant reduction in the overall prevalence of STH infection compared to the baseline survey of 2014. The state achieved effective programmatic action against schistosomiasis across the 26 LGAs, with all the wards visited having a prevalence threshold below the WHO recommendation. The state also recorded significant achievement in the reduction of prevalence of STH with a 30% reduction in overall prevalence, and varying reduction in prevalence across the LGAs with annual PC required in 1 LGA (Ika) once in 2 years, annual PC required in 10 LGAs (Abak, Etim Ekpo, Etinan, Ibiono Ibom, Ikono, Ikot Ekpene, Itu, Nsit Ibom, Ukanafun, and Uyo) for 5 years and biannual PC required in 15 LGAs (Essien Udim, Eket, Ibesikpo Asutan, Ini, Mbo, Mkpat Enin, Nsit Atai, Nsit Ubium, Obot Akara, Okobo, Oron, Oruk Anam, Udung Uko, Uruan, Urueoffong/Oruko) for 5 years. However, for STH, no LGA has met the WHO treatment threshold of less than 2% for stopping MDA, which mandates the need to intensify effort in the control of STH [15]. Despite the significant reduction in the prevalence of STH, factors such as lack of drugs, delayed supply chain, inability to conduct 2 rounds of MDA in some LGAs requiring such regimen must have affected the high prevalence observed in some LGAs.
The persistent dominance of hookworms (15.38%) is a significant public health concern, particularly due to its direct association with anaemia and cognitive impairment in children. In Ondo State, Nigeria [16], a study reported Trichuris trichiura as the most dominant species of STHs. The difference might be due to factors such as ecological and environmental differences. The observed statistically significant difference in infection rates between males and females suggests differential exposure to environmental risk factors, which must inform targeted behavioural change communication strategies. A similar observation was reported in a previous study in Plateau State [17]. Children in the age group of 11–14 years were affected more, indicating exposure to more high-risk environments and behaviours associated with that age. A study reported the same pattern for that age group of 11–14 years in Ondo State, Nigeria [1].
The survey confirms heterogeneity in prevalence with significant variation in the distribution of the parasites across the LGAs, which indicates the need to identify key elements resulting to the spatial variation in prevalence across the state, a programmatic challenge that should be tailored alongside chemotherapy for an intensified and concerted intervention package. Such packages include identifying non-functional basic water, sanitation and hygiene infrastructures, improvement in access and use of WASH through behavioural change, health and nutrition education, among other. The WHO recent guidelines emphasize on the need for improved access to water, sanitation and hygiene infrastructures [7].
Availability of toilets in schools, and the type of toilet available in the school environment for defecation, was a significant risk factor influencing the prevalence of STH in Akwa Ibom State. Similar observation was reported in Ekiti State [18], Kogi State [19] and Cross River State [20]. Also, clean-up behaviours in schools were found to be a significant contributor of infection. Children who urinated or defecated freely around the school compound had the highest rates of infection. This observation implies that a lack of school sanitation facilities, poor maintenance, or overcrowding could be making a significant contribution to the transmission. Enhancement of school WASH and better behaviour change communication among the pupils are still important actions that should be incorporated into the control programs [21]. Failure and ineffective performance of the control program caused by lack of access to WASH have been reported in different countries [22–25].
In general, this assessment confirms that the transmission of soil-transmitted helminth parasites in these communities is influenced by the combination of environmental, behavioural, and infrastructural-related elements. The responses to the determinants must be integrated in health, education, water, hygiene and sanitation. The integration and utilization of the novel diagnostic technologies, such as the AiDx digital microscope, has proven to be a good complement to microscopy in accelerating laboratory analysis time and enhancing data throughput for time-sensitive programmatic decisions [13,14,18].
5 Conclusion
Preventive chemotherapy (PC) program for schistosomiasis and soil-transmitted helminthiasis (STH) in Akwa Ibom state has proven highly effective for schistosomiasis with 0.0% prevalence compared to baseline of 0.0 to 1.2% but partly effective for soil-transmitted helminthiasis with overall prevalence of 27.62% (ranges from 4.92 – 71.65%) compared to baseline of 25.1 to 91.4% with a 30.15% reduction in prevalence. The survey documented a reduction in STH prevalence across all 26 LGAs; 1 LGA require PC once in two years, 10 LGAs require annual PC, and 15 LGAs require biannual PC. For SCH, continued case management is recommended across all 26 LGAs. The widespread absence of functional WASH facilities in schools remains a critical risk factor threatening the long-term sustainability of MDA-driven gains. These findings underscore the imperative for sustained treatment and control programmes, underpinned by substantive improvements in water, sanitation, and hygiene infrastructure.
Supporting information
S1 Data. Akwa Ibom State 2025 Survey on schistosomiasis amd soil transmitted helminths.
This dataset contains laboratory results and risk factors associated with Schistosomiasis and Soil-transmitted helminths in 26 Local Government Areas of Akwa Ibom State.
https://doi.org/10.1371/journal.pntd.0014603.s001
(XLSX)
Acknowledgments
We thank the Federal Ministry of Health and Social Welfare (FMOHSW), Akwa Ibom State Ministry of Health, Helen Keller Intl, The END Fund and the HIS for their support during this study.
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