Evidence of reduced academic performance among school children with helminth infection independent of nutritional status

Soil transmitted helminths (STH) pose a formidable health risk to school-age children in resource-limited settings. Unfortunately, mass deworming campaigns have been derailed since the onset of the COVID-19 pandemic. The present study assessed the cross-sectional associations between STH, nutritional status and academic performance of school children in the Banda District of Ghana. School children (5–16 years) (n=275) were recruited through both school and household visits by community health workers using a multi-stage cluster sampling technique. Weight and height measurements were taken for anthropometry, as well as stool microscopy. Data is presented as frequency and percentage. Infection Status a : infection with either intestinal parasite and/or blood protozoa. Intestinal parasite Infection Status b : infection with either intestinal helminth and/or intestinal protozoa. Mixed Infection c : A combination of blood-borne protozoa and intestinal parasites.


Introduction
School-age children in developing countries are at risk of compromised health as a consequence of helminth infections (1,2). Although helminth infections do not produce high mortality statistics, recent estimates suggest that morbidity due to helminth infections accounts for an estimated 20% of the disability-adjusted life years lost due to infectious diseases in children less than 14 years old (3). Among the well-described morbidities associated with helminth infection in children are under-nutrition, anemia, and failure to achieve genetic potential for growth (3). Much like other diseases of poverty, the burden of STH is disproportionately high in developing countries and affect children living in extreme poverty, particularly those living in rural communities or urban communities without adequate access to good water, sanitation, and hygiene (WASH) (2). In sub-Saharan Africa, estimates of the prevalence of hookworm (Ancylostoma duodenale and Necator americanus) range from 30-50% (4). Environmental factors present in tropical climates are known to be conducive to the life-cycle of intestinal helminths that have been marked for eradication. Furthermore, soil transmitted helminths are thought to deepen inequality in society as well by widening of the wealth gap by adversely affecting future economic potential of children from poor socio-economic background (5). Then came the pandemic. The COVID-19 pandemic had broad-range disruptive effects on in-country programmes targeted at several neglected tropical diseases (NTDs) including school deworming campaigns. In the Bono Region, all deworming campaigns halted in the wake of the pandemic as a result of the strain placed on the health service by the pandemic. Indeed, the Ghana Health Service had to readjust programme goals in order to mobilize adequate resources to manage the public health threat imposed by the pandemic. In addition, the Government ordered the closure of all basic schools for an entire academic year, effectively bringing an end to all school health programs. In the midst of all the chaos, drugs intended for distribution in rural communities where the greatest burden of soil transmitted helminths expired as a result of these extended lockdowns. Meanwhile, children continued to be exposed to community factors that placed them at heightened risk of infection with soil transmitted helminths with no access to drugs (7).
Several studies have highlighted a gap in knowledge and policy setting regarding the value of school deworming campaigns and children's academic performance or cognitive function (8-10). However, data on helminth infection in Ghana has largely focused on prevalence estimates for health disability and not on children's academic performance. The aim of the present study is to investigate the effect of soil transmitted helminth infections on growth (nutritional status) and cognitive function in school children in the Bono Region of Ghana in light of demographic, socio-economic, and epidemiologic contextual factors such as COVID-19 induced suspension of mass school-based deworming campaigns.

Methodology
Study design and setting A cross sectional survey design was employed to determine the prevalence of intestinal helminths, anemia and academic performance among school children in the Banda district of the Bono Region of Ghana ( Figure 1). The Banda District is made up of a number of riparian communities covering a total land area of 2,298.3 square kilometres in the middle belt of Ghana. It is home to a population of approximately 25,000 people. Majority of the inhabitants (71.2%) nd employment as skilled agricultural, forestry and shery workers. The district is entirely rural with a youthful population. The District has a household population of 20,171 with a total number of 3,685 households. The average household size in the District is about 6 persons per household. Children constitute the largest proportion of the household members (41.7%). The three main sources of lighting in dwelling units in the District are electricity (46.3%), ashlight/torch (40.4%) and kerosene lamp (11.8%). The main source of fuel for cooking for most households in the District is wood (75.5%). The four main sources of water in the District are borehole, river stream, public tap and pipe borne water (96.4%). Almost six percent of the households drink water from river or stream, while 0.4 percent drinks water from dugout/pond/lake/dam/canal. The most commonly used toilet facility in the District is open defaecation in the bush/ eld accounting for 43.9 percent followed by public toilet (34.2%). Only 3.4 percent of the households in the District have WC toilet facility. With reference to school attendance, of the population aged 3 years and above, 62.5 percent are currently attending school and 37.5 percent have attended in the past.

Sampling technique and data collection
A total of 275 school-aged children (5-16 years) were recruited through school visits by community health workers using a multi-stage cluster sampling technique. The study was conducted in seven (7) selected basic schools three (3) of which were under private ownership. The register of schools in the district were obtained from the School Health Education Programme (SHEP) o ce. Schools were clustered according to location and strati ed according to educational level (basic grade 1-9). Allocation of the students to schools and grade level were performed according to the number of students in each school and grade (Supplementary File 1: Allocation of schools). Study subjects were selected by systematic random sampling using the class roster as the sampling frame in each school. A validated and pretested questionnaire based on known risk factors was administered to each child-parent pair by trained eld workers with translation to local dialect where necessary. Data about socio-demographic characteristics and risk for intestinal helminthic infections were retrieved through face-to-face interviews with parentchild units. Afterwards, blood samples were collected into K 3 EDTA and gel tubes. Stool samples were collected into labeled, clean, and dry stool containers and preserved with 10% formalin before they were transported to the Banda District hospital laboratory. Weight and height measurements were taken in duplicate with minimal clothing, without shoes, and the mean values recorded. The anthropometric index of Z-score for weight-for-age was computed as an indicator of growth status for school children using Anthroplus software version 1.0.4 (WHO, Geneva). School children were classi ed as underweight if they had Z-score values less than 2 times the SD for weight-for-age. The academic performance of the students was measured as the cummulative end-of-term examination results averaged over 3 consecutive school terms.

Laboratory procedures
Preserved stool samples were processed using the formalin-ether concentration method (11). Brie y, a portion of stool weighing approximately 2g was placed in a separate stool container and mixed with 10ml of 10% formalin, ltered through two layers of gauze into a 15ml centrifuge tube and centrifuged at 2000 rpm for 2 min. The sample was stirred thoroughly and incubated for 5 minutes before addition of 3ml diethyl ether and centrifugation at 2000 rpm for 2 minutes. The supernatant was discarded and the sediment was used to prepare a smear on a microscopic slide for observation of parasite ova. Blood lms (thin and thick) were prepared and examined according to WHO guidelines to check for the presence of blood parasites (Plasmodium) (1). Haemoglobin concentration levels were measured on an automated analyser (SYSMEX KX-21N, Chuo-ku, Kobe, Japan) using whole blood collected in EDTA test tubes.

Statistical analysis
Statistical Package for Social Sciences (SPSS) for windows version 25.0 was used to analyse collected data. Associations between variables and were tested via bivariate analysis (chi-square test). Bivariate correlations, independent T-tests, and multiple regression analyses were performed to investigate associations between academic performance, helminth infection and nutritional status. Participants recruited for the study provided written informed consent (i.e. the participants gave assent and their parents gave consent).
All the individuals diagnosed to have intestinal protozoan infections were given metronidazole (Flagyl) orally as standard adult dose (800 mg) or standard paediatric dose (200-400mg) 8-hourly for ve days. Furthermore, those found to have schistosome infection received a standard oral dose of praziquantel (40 mg/kg body weight). Children infected with intestinal helminths received albendazole (400 mg) in a single dose as recommended by the NTD programme and standard treatment guidelines of the Ghana Health Service.

Results
A total of 275 school children aged 5 to 16 years were recruited for the study. All of them provided a blood sample and stool sample. Demographic characteristics of the participants are shown in Table 1. The mean age of the children was 11.1 years (SD: ± 2.4 years). Majority of the participants were females accounting for 156 (56.7%) of the total study population. Approximately two-thirds (65.8%) of study participants were descended from the Mole-Dagbani ethnicity and the rest were mostly Akans (31.3%) with a minority group of Ga-Adangbe descent. The major religious persuasion was Islam (56%). Majority of the participants were attending public schools under the Ministry-funded meal supplementation programme (73.1%). The mean blood haemoglobin concentration was recorded as 10.9 g/dL (SD: ±1.7 g/dL). Data is presented as frequency and percentage.    Academic performance scores averaged over two school terms were compared across categories of socio-demographic variables (Table 5). Children from low-income households (52.5±12.9) performed poorly compared to children from households with higher income (59.6±15.0).  Table 7.

Discussion
In the wake of the rst cases of SARS CoV 2 infections in Ghana, the Government took several precautionary measures to avoid community-spread and contain the virus. As part of these measures, school activities were suspended and school children had to stay at home for over a year. By compelling national authorities to lock down schools, the COVID-19 pandemic completely disrupted mass drug administration campaigns previously held in schools. Furthermore, children staying at home faced a greater risk of reinfection from community-acquired helminths (7). Once restrictions had been eased and schools allowed to reopen, the present study investigated the burden of helminth infections in an endemic community and to investigate the cross-sectional relationship with nutritional status and school performance.
A high burden (40.4: 95% CI: 34.6% -46.2%) of STH was detected among school children. Several classes of intestinal parasites were present in stool samples collected from school-age children: these included Taenia spp., Schistosoma spp., Strongyloides spp., Ascaris spp., and Entamoeba spp. Estimates of the prevalence of STH among school children in Ghana have ranged from 6-45% (4, 12, 13) under varying contexts. Abera et al., (2014) recorded a prevalence of 41.46 percent in an area in Northern Ethiopia, while Davies and colleagues also recorded a frequency of 40.5 percent and 40.7 percent among preschool and school-aged children, respectively (14,15). The prevalence of hookworms (Ancylostoma duodenale and Necator americanus) was however much lower in the present study than what had been previously known (30-50%) prior to the onset of MDA in schools (16,17).
In Ghana, sporadic community-based administration of anti-helminth agents to school children in targeted communities as part of eradication efforts have been reported to lower the burden of helminths reported in communities with such a history (17). The low prevalence of hookworm may re ect the impact of previous deworming campaigns in the Region (4). However, this may be di cult to prove in the absence of pre-MDA campaign data on the Banda District where the present study was conducted.
Nevertheless, the burden of intestinal parasites and helminths is higher than other estimates in schoolage children from the region (4,(18)(19)(20). In addition, they remain far above elimination targets set by the WHO. The variation in prevalence might be due to research scheduling, participant sampling, seasonal changes in survey conduct, environmental circumstances, or other geographical characteristics in these study locations.
The higher-than-expected burden of soil transmitted helminths discovered among school-age children several months after a mass deworming exercise in the Region might be indicative of persistent reinfection patterns (7) and re ect the impact of the pandemic in diminishing control efforts implemented through the school system. In the absence of control measures aimed at reducing exposure, treatment of STH infections will naturally be followed by avoidable re-infection, necessitating repeated treatments (21,22). As such, to sustain the bene ts of treatment well beyond campaign periods and to preempt the adverse effects of future public health shocks such as the COVID-19 pandemic on gains made through MDA programmes, efforts to reduce environmental exposure to infection through improved sanitation and hygiene behaviors must be prioritized (23)(24)(25). Transmission of protozoa that live in a human's intestine to another human typically occurs through the fecal-oral route (for example, contaminated food or water or person-to-person contact). Thus, the high prevalence of Entamoeba spp. in the community would suggest that insanitary conditions exist that need to be improved.
Inhabitants living in close proximity to water bodies have been reported to maintain signi cantly elevated relative risks for helminth infections and might also be a reason for the burden of helminths observed in the Banda District of the Bono Region where contact with stagnant water bodies is an important part of daily life especially for children who are continuously exposed to contaminated soil and water and often lack the awareness of good personal hygiene. Gyasi et al., (2019) investigated the incidence and the prevalence of Schistosoma haematobium infection in riparian communities of the Bui dam. The study revealed that, S. haematobium was more prevalent among inhabitants living closer to the Bui dam with children less than 14 years of age being the worst affected (26). As a result, control efforts must factor the contextual requirements within such geographic locations in order to achieve and sustain programme targets.
In general, a high burden of intestinal parasites and helminths in particular have been strongly linked with poor nutritional status and anaemia (3). The high prevalence of anaemia among school children in the study area and the signi cant cross-sectional association between intestinal parasite infection and suboptimal haemoglobin concentration con rm this assertion (Table 3). When unchecked, poor nutritional status and anaemia may undermine academic performance in school children. However, the present data did not reveal an association between poor nutritional status and academic performance. A number of reasons may be ascribed to this including the broad age range (5-16) and the sensitivity of markers of nutrition across the age spectrum (1,27). More comprehensive nutritional assessment based on anthropometric, biochemical and clinical data is required to con rm this nding.
Rather, academic performance averaged from scores over two school terms was signi cantly associated with intestinal parasite status (Tables 5-7). A number of similar studies have reported concordant ndings (8, 28). This adds to the growing body of data in support of an association between academic performance of school children and helminthiasis (Supplementary le 2: Determinants of school children's academic performance over past year). Several mechanisms have been put forward to explain this association, including an improvement in school attendance following mass deworming of school children during the academic year (13). Not all studies report a signi cant relationship between children's cognitive performance and their anthropometric and helminthiasis data (29). In addition to intestinal parasite status, low household income level was associated with poor academic performance. Children from low-income households performed poorly compared to children from households with higher income (Table 5-7). Academic performance is an important socioeconomic objective for every society. In the broadest sense, it provides an indication of the fortunes of the society in the near future. However, this nding suggests that signi cant investment may be needed to offset household poverty and guarantee quality educational outcomes. Recognizing this, the Government has introduced a policy to provide free school meals to school children. However, aside meal supplementation, mass deworming campaigns may be crucial for attaining expected educational targets.

Conclusion
Data collected immediately after the easing of COVID-19 restrictions among school children in the Banda District of Ghana show that the prevalence of soil transmitted helminths is 40.4% and higher than programme targets. Commonly detected intestinal parasites were Taenia spp., Schistosoma spp., Ascaris spp., Ancyclostoma spp. and Trichuris trichiura. Helminth infection, either independently or together with Entamoeba spp., household income and z-scores for weight-for-age may be important predictors of academic performance for school children. School children with intestinal parasite infection had poorer academic performance compared to uninfected children, in spite of their nutritional status. In addition to school-feeding programmes, consistent mass drug administration campaigns may be critical for improving learning outcomes in young school children.

Declarations
Authors' contributions ETD, DB, SFG and MTY conceived the study; KBO, WIOB and JEO designed the study protocol and trained eld and laboratory staff; JEO, BAA and SKA carried out the clinical assessment; OD, SA and ASR carried out the laboratory and data analysis and interpretation. ETD, AGAA and OD drafted the manuscript; BAA, SFG and WIOB critically revised the manuscript for intellectual content. All authors read and approved the nal manuscript. ETD and DB are guarantors of the paper Nutritional status of school children.

Supplementary Files
This is a list of supplementary les associated with this preprint. Click to download. Additional le1bandaselectedschools.pdf Additional le2.docx