Sarah Bick

Introduction: Diarrhoea and lower respiratory infections remain leading causes of under-five mortality in sub-Saharan Africa. Handwashing with soap (HWWS) is a cost-effective intervention, yet adherence remains low. Effective interventions must address multiple behavioural influences, as knowledge alone is insufficient without supportive environments. Multi-component handwashing interventions target diverse behavioural determinants, yet few studies disentangle the isolated and combined effects of different components. This multi-arm randomised-controlled trial in Lusaka, Zambia, aims to assess the isolated and combined effects of hand hygiene behaviour promotion and handwashing hardware and supply provision on HWWS at handwashing opportunities, strengthening the evidence base for designing sustainable handwashing interventions. Methods and analysis: This superiority, multi-arm, parallel group randomised-controlled trial will be conducted in five peri-urban communities in Lusaka, Zambia, with 1800 households randomly assigned to four arms (450 households per arm; 1:1:1:1): (A) handwashing hardware and supply provision only, (B) hand hygiene behavioural promotion only, (AB) hand hygiene behavioural promotion+hardware and supply provision, and (C) control (no intervention). Households receiving the hardware and supply intervention (A, AB) will receive a handwashing facility and supplies to make liquid soap solution with a maintenance check after 3 months. Households receiving the hand hygiene behaviour promotion intervention (B, AB) will receive five bi-weekly visits with a sixth follow-up visit 5 weeks later. HWWS behaviour of one household member will be assessed through structured observations at baseline and endline (6 months after intervention delivery begins). Ethics and dissemination: Ethical approval was obtained from London School of Hygiene & Tropical Medicine, Research Ethics Committee, London, UK (Ref: 31387), the University of Zambia Biomedical Research Ethics Committee (Ref: UNZABREC 5834–2024) and the Zambia National Health Research Authority (NHRA −1823/23/12/2024). Results of the main trial will be submitted for publication in a peer-reviewed journal. Trial registration number: NCT06865495 .

Food contamination contributes to 40% of childhood diarrhoea cases globally. It occurs when pathogens are transmitted from faecal matter to food through the faecal oral route. Food hygiene can prevent food contamination and improve the microbial quality of weaning foods in domestic settings. However, context specific evidence is needed to identify risk factors associated with food contamination, especially in complex low-income communities. Our study used a modified Hazard Analysis Critical Control Point approach to assess the quality of weaning foods and identify associated risk factors in a low income setting of Lusaka, Zambia. We enrolled 60 caregivers of children aged < 1 year who had begun complementary feeding and collected data on household characteristics and food hygiene behaviours using surveys and structured observations. We collected samples of complimentary foods prepared for the child and tested them for Escherichia coli (E. coli) using the IDEXX Colilert-18 method. Multivariable logistic regression was performed to determine risk factors associated with food contamination. Of 59 food samples, 17 (29%) were contaminated with E. coli . Porridge (AOR = 0.04; 95% CI: 0.01, 0.28; p = 0.001) and non-animal source foods (AOR = 0.11; 95% CI: 0.02, 0.69; p = 0.019) were associated with lower odds of contamination compared with animal source foods. Heating of food was also associated with lower odds of contamination but was not significant. Food hygiene behaviours including utensil and surface cleaning were seldom practiced (17% and 15%, respectively), and handwashing with soap before food preparation was not practiced. Our study identifies the microbiological risk associated with animal source foods and the potential health risk posed to weaning children. Nutrition guidelines should take into consideration this risk as programs promote an increased uptake of animal source foods in child diets.

Background Children under the age of 5 bear the highest burden of disease related to inadequate water, sanitation and hygiene (WASH). However, evidence of the effectiveness of WASH interventions in preschool settings is limited. Nested within a cluster-randomised controlled trial in Addis Ababa, Ethiopia, this substudy evaluated the impact of a water and hygiene intervention on health and school attendance among preschool children. Methods Schools were randomly assigned 1:1 to receive the intervention during the 2021/2022 academic year or the following year (waitlist control). We included schools enrolled in the main trial with preschool classes and randomly selected and allocated additional schools with preschool classes to reach 20 schools in each arm. The intervention comprised school-wide infrastructure improvements (water storage and filtration systems, drinking water and handwashing stations) and hygiene behaviour change promotion. Planned sanitation improvements were not delivered within the trial duration. Within each school, we randomly selected 20 preschool pupils (ages 3–6), recording caregiver-reported diarrhoea, respiratory illness and absence over four consecutive weekly telephone interviews with caregivers of the selected pupils from April to June 2022, following intervention delivery. Results We found no evidence of effects on caregiver-reported diarrhoea (adjusted odds ratio (aOR) 0.85; 95% CI 0.46 to 1.59; p=0.61), respiratory illness (aOR 0.84; 95% CI 0.60 to 1.17; p=0.30) or absence (aOR 0.75; 95% CI 0.51 to 1.08; p=0.13). Conclusions Dropout of three schools and challenges in telephone-based data collection resulted in large loss to follow-up, reducing statistical power. Further research should examine improving telephone-based methods to obtain sufficient follow-up data for school-based evaluations.

Introduction: Diarrhoea and lower respiratory infections remain leading causes of under-five mortality in sub-Saharan Africa. Handwashing with soap (HWWS) is a cost-effective intervention, yet adherence remains low. Effective interventions must address multiple behavioural influences, as knowledge alone is insufficient without supportive environments. Multi-component handwashing interventions target diverse behavioural determinants, yet few studies isolate the individual and combined effects of different components. This multi-arm randomised-controlled trial in Lusaka, Zambia, aims to assess the individual and combined effects of hand hygiene behavioural promotion and handwashing hardware and supply provision on HWWS at handwashing opportunities, strengthening the evidence base for designing sustainable handwashing interventions. Methods and analysis: This superiority, multi-arm, parallel group randomised-controlled trial will be conducted in five peri-urban communities in Lusaka, Zambia, with 1800 households randomly assigned to four arms (450 households per arm) (1:1:1:1): (A) Handwashing hardware and supply provision only, (B) Hand hygiene behavioural promotion only, (AB) Hand hygiene behavioural promotion + hardware and supply provision, (C) control (no intervention). Households receiving the hardware and supply intervention (A, AB) will receive a handwashing facility and supplies to make liquid soap solution with a maintenance check after three-months. Households receiving the hand hygiene behavioural promotion intervention (B, AB) will receive five bi-weekly visits with a sixth follow-up visit four weeks later. HWWS behaviour of one household member will be assessed through structured observations at baseline and endline (6-months after intervention delivery begins). Ethics and dissemination: Ethical approval was obtained from London School of Hygiene and Tropical Medicine, Research Ethics Committee, London, UK (Ref: 31387), the University of Zambia Biomedical Research Ethics Committee (Ref: UNZABREC 5834-2024) and the Zambia National Health Research Authority (NHRA-1823/23/12/2024). Results of the main trial will be submitted for publication in a peer-reviewed journal. Trial Registration Number: NCT06865495; ClinicalTrials.gov; Pre-results; Initial release date 04-Mar-2025 STRENGTHS AND LIMITATIONS: The study provides an opportunity to directly assess the individual and combined impact of handwashing hardware and supply provision and behavioural promotion on handwashing with soap, which can inform future hand hygiene promotion programmes. The large study sample and comprehensive outcome measures will provide unique information about the individual and combined effects of intervention components on behaviour and health. While structured observations have inherent limitations (participants may alter their behaviour when they are aware they are being observed), it remains the gold standard for the measurement of routine behaviours in domestic contexts. The lack of blinding of study participants and limited blinding of assessors collecting data is a limitation to the study design. This is an acknowledged challenge in the behavioural and environmental health research sector. Since the intervention is implemented at the household level, there is some potential for contamination of the intervention message between households within communities. However, this risk is minimal given the large sampling interval. Contamination will be assessed during endline data collection.

School-age children in low-income and middle-income countries (LMICs) face health and educational challenges due to inadequate water, sanitation and hygiene (WASH) in schools (WinS). Evidence for the impact of WinS interventions is limited and inconsistent, and previous systematic reviews have faced challenges in synthesising data due to varied interventions, study designs and outcome measures, although most do not examine this variability in more detail. This scoping review identified 83 experimental studies from 33 LMICs measuring a primary or secondary health or educational outcome among pupils, published up to November 2023, using a systematic search of seven databases and searching of reference lists of previous systematic reviews and included articles. These included 65 studies (78%) not included in previous WinS reviews and encompassed 313 intervention effects across 14 outcome domains. Interventions comprised an array of WASH technologies and approaches, often combining infrastructure and behaviour change methods and frequently integrated with other school-based initiatives like deworming. 36 studies (43%) measured only behavioural or knowledge outcomes. Our comprehensive inventory of study outcomes identified 158 unique outcome measures, with 72% measured in exactly one study. Common outcomes included parasitic infections, anthropometric measures and school absence, but approaches to measurement varied widely even for similar outcomes. Only 7% of results were disaggregated by gender, limiting assessment of differential impacts. Our findings underscore the need for standardised outcome measures in WinS research incorporating a complete definition of the assessment and aggregation approach, greater attention to gender-specific impacts, and further exploration of modalities and functions of WinS interventions alongside novel meta-analysis methods to disentangle effects of diverse intervention components.

School-age children in low- and middle-income countries (LMICs) face health and educational challenges due to inadequate water, sanitation and hygiene (WASH) in schools (WinS). Evidence for the impact of WinS interventions is limited and inconsistent, and previous systematic reviews have faced challenges in synthesising data due to varied interventions, study designs, and outcome measures, although most do not examine this variability in more detail. This scoping review identified 83 experimental studies from 33 LMICs measuring a primary or secondary health or educational outcome among pupils, published up to November 2023, using a systematic search of seven databases and searching of reference lists of previous systematic reviews and included articles. These included 65 studies (78%) not included in previous WinS reviews and encompassed 313 intervention effects across 14 outcome domains. Interventions comprised an array of WASH technologies and approaches, often combining infrastructure and behaviour change methods and frequently integrated with other school-based initiatives like deworming. 36 studies (43%) measured only behavioural or knowledge outcomes. Our comprehensive inventory of study outcomes identified 155 unique outcome measures, with 72% measured in exactly one study. Common outcomes included parasitic infections, anthropometric measures, and school absence, but approaches to measurement varied widely even for similar outcomes. Only 7% of results were disaggregated by gender, limiting assessment of differential impacts. Our findings underscore the need for standardised outcome measures in WinS research incorporating a complete definition of the assessment and aggregation approach, greater attention to gender-specific impacts, and further exploration of modalities and functions of WinS interventions alongside novel meta-analysis methods to disentangle effects of diverse intervention components.

Soil-transmitted helminths (STHs) are among the most common human infections worldwide and a major cause of morbidity. They are caused by different species of parasitic worms and transmitted by eggs released in faeces or when hookworm larvae penetrate the skin. The main control strategy in endemic regions is periodic treatment with deworming medication. In the last 10 years, there has been a scale-up of prevention and control activities with a focus on community-based interventions (CBIs). This review aims to systematically analyse the impact of CBIs on the prevalence and infection intensity of STHs. A systematic review was published on this topic in 2014, but there have subsequently been several new studies published which are included in this review. Electronic database search of MEDLINE (Ovid), Global Health Online (Ovid), Cochrane Library, Embase (Ovid) and Web of Science was conducted. Titles, abstracts, and full texts were screened by two independent reviewers according to predefined eligibility criteria. Data were extracted and a meta-analysis of included studies was conducted. A total of 11,954 de-duplicated titles were screened, and 33 studies were included in the review. 14 focussed on community-wide treatment, 11 studies investigated school-based interventions, and 3 studies investigating both. Results suggest that CBIs are effective in reducing the prevalence of Hookworm, Trichuris trichiura and Ascaris lumbricoides. School-based treatment and community-wide treatment, as well as annual and semi-annual deworming, all reduce STH prevalence significantly. Mass drug administration was effective in reducing the infection intensity of Hookworm (Mean difference: -211.36 [95% CI: -519.12, 96.39]), Trichuris trichiura (-736.69 [-1349.97, -123.42]) and Ascaris lumbricoides (-2723.34 [-5014.85, -431.84]). The results suggest that CBIs are effective in reducing the prevalence and intensity of STH infections. While most studies delivered preventive chemotherapy (PC), few studies explored the impact of interventions such as water, sanitation, and hygiene (WASH) or health education, which may be essential in preventing reinfection after PC.

Objectives This multicountry analysis aimed to assess the prevalence of key hygiene prevention behaviours and their determinants, associated with international non-governmental organisation (WaterAid) hygiene behaviour change programmes for COVID-19 prevention. The goal of this analysis is to inform future outbreak preparedness and pandemic response in low and middle-income countries. Design Cross-sectional study. Setting Households in seven countries where WaterAid implemented a first-phase COVID-19 response programme in 2020 (Ethiopia, Ghana, Nepal, Nigeria, Rwanda, Tanzania and Zambia). Participants 3033 adults (1469 men and 1564 women, alternately sampled from one household to the next to maintain gender balance) in specific programme areas (211 villages) surveyed between October and November 2020. Primary outcome measures Self-reported primary outcomes were: a composite measure of HWWS for prevention of respiratory infection/COVID-19 (total of 5 key moments); respondent increased HWWS behaviour after the COVID-19 pandemic; respondent always wears a mask in public spaces; respondent always practices physical distancing in public spaces. Results Most respondents (80%) reported increasing their handwashing behaviour after the pandemic, but practice of HWWS at COVID-19-specific prevention moments was low. Mask wearing (58%) and physical distancing (29%) varied substantially between countries. Determinants of key behaviours were identified, including age and socioeconomic status, perceived norms, self-regulation and the motive of protecting others. Incidence rate ratios or odds ratios and 95% CIs for a range of psychosocial determinants for each of the four primary outcomes are reported. Conclusions These findings highlight that leveraging behaviour-specific emotional drivers and norms, reducing common barriers and promoting targeted messages about specific behaviours and actions individuals can take to reduce risk are necessary to support large-scale behaviour change. Learning from the COVID-19 response to more effectively integrate novel behaviours into existing health promotion will be vital for disease prevention and outbreak resilience.

Whilst improving hygiene and sanitation behaviours is key to cost-effective and sustainable WASH interventions, measuring behaviour change remains a challenge. This study assessed the validity and reliability of pictorial 24-hour recall (P24hR), a novel method using unprompted recall of past activities through pictures, compared to structured observation for measuring handwashing with soap (HWWS) and safe child faeces disposal in rural Malawi. Data were collected from 88 individuals across 74 households in Chiradzulu district using both methods over a two-day period, with the recall period of the P24hR corresponding to the period of structured observation completed the previous day. Results showed poor agreement between P24hR and observations in detection of hygiene opportunities and behaviours. P24hR under-reported handwashing opportunities when frequency was high and over-reported them when frequency was low. The 95% limits of agreement for handwashing opportunities estimated through Bland-Altman analysis (-7.62 to 4.89) were unacceptably wide given median 5 opportunities observed per participant. P24hR also over-reported HWWS and safe child faeces disposal, and kappa statistics indicated agreement no better than by chance. Structured observation remains the preferred method for measuring hygiene behaviours despite its known limitations, including potential reactivity bias.