State of deworming coverage and equity in low-income and middle-income countries using household health surveys: a spatiotemporal cross-sectional study

A comprehensive assessment of deworming coverage among pregnant women in low- and middle-income countries, 2000-30

Background

Intestinal parasitic infections pose a significant global public health issue, particularly among pregnant women, who are generally more susceptible due to their elevated need for iron and nutrients. Deworming stands as a secure and efficacious public health intervention. The World Health Organization (WHO) set a target for the national deworming coverage rate among pregnant women at 75% by 2030. Nonetheless, the existing body of evidence on deworming among pregnant women in low- and middle-income countries (LMICs) remains limited.

Methods

Based on Demographic Health Survey (DHS) data from 56 LMICs (n = 924 277) between 2000 and 2022, we used Bayesian hierarchical models to estimate trends of deworming coverage up to 2030 and to analyse determinant factors of deworming.

Results

We found that, despite progress in deworming coverage estimates for most countries, only 11 (<20%) are on track to achieve the WHO target coverage at the national level. Inequality gaps were projected to increase in most LMICs. A multilevel model showed that increased numbers of antenatal care, access to safe water, and a higher wealth index were associated with higher odds of deworming.

Conclusions

The progress on deworming coverage and inequality in many countries remains insufficient for achieving the WHO target by 2030. Additional investments in the health sector towards the expansion of deworming programmes, along with integration with existing health services, are urgently required, as is the introduction of effective policies and strengthening programmes within the context of the 'Leave No One Behind' agenda.

Deworming coverage and its determinants among 12-59 months old children in East Africa: A population-based study

BACKGROUND

Intestinal parasitic infections are the world's largest public health issue, primarily in developing nations. The World Health Organization (WHO) recommends deworming as a preventative or therapeutic measure for all vulnerable people residing in endemic areas. Despite this issue, there is little data on the prevalence and associated factors of deworming drug use among children under five years of age in East Africa.

OBJECTIVE

This study aimed to evaluate the prevalence and contributing factors of deworming coverage among children under the age of five in East Africa using the most available national health survey data.

METHODS

Data from the Demographic and Health Survey, which included 103,865 weighted children between the ages of 12-59 months, were used in this investigation. Our outcome of interest was taking deworming medicine six months before the interview. A logistic regression model was then fitted. A cutoff P value of 0.2 was used in the binary logistic regression analysis. To identify significant variables, a 95% confidence interval and adjusted odds ratio (AOR) with a value < 0.05 were used.

RESULTS

The prevalence of deworming in East Africa was 54.13% (95% CI: 53.83%-54.43%). The maternal age group of 24-34 years, and from 35-49 years (AOR = 1.37, 95% CI, 1.32,1.42), and (AOR = 1.71, 95% CI, 1.62,1.79), employed women (AOR = 1.62, 95% CI, 1.58,1.67), being from rural(AOR = 1.11,95% CI,1.07,1.15), unmarried mothers (AOR = 1.12,95% CI,1.09,1.15), mothers from poorer, middle, richer, and richest households (AOR = 1.16,95% CI, 1.12,1.21), (AOR = 1.23, 95% CI, 1.18,1.28), (AOR = 1.22,95% CI, 1.16,1.27), and (AOR = 1.27, 95% CI, 1.21,1.34) having at least one antenatal care follow up(AOR = 2.90, 95% CI, 2.63,3.16), health facility delivery(AOR = 1.69, 95% CI,1.64,1.75), mass media exposure AOR = 1.32, 955 CI, 1.29,1.36), having of 3-5 children (AOR = 0.89, 95% CI, 0.86,0.93), more than five children (AOR = 0.79, 95% CI, 0.73,0.86), and parity of 2nd or 3rd birth order (AOR = 1.05, 95% CI, 1.01,1.09) as compared to primi mothers were associated with the deworming among under five children in east Africa respectively.

CONCLUSION

The under-five population in East Africa had a lower prevalence of deworming medication per the most recent DHS findings. Promoting mother and child health services (antenatal care, institutional delivery, family planning), as well as women's empowerment, should be prioritized.

Integrating and coordinating programs for the management of anemia across the life course

Anemia is a major global public health concern with a complex etiology. The main determinants are nutritional factors, infection and inflammation, inherited blood disorders, and women's reproductive biology, but the relative role of each varies between settings. Effective anemia programming, therefore, requires evidence-based, data-driven, contextualized multisectoral strategies, with coordinated implementation. Priority population groups are preschool children, adolescent girls, and pregnant and nonpregnant women of reproductive age. Opportunities for comprehensive anemia programming include: (i) bundling interventions through shared delivery platforms, including antenatal care, community-based platforms, schools, and workplaces; (ii) integrating delivery platforms to extend reach; (iii) integrating anemia and malaria programs in endemic areas; and (iv) integrating anemia programming across the life course. Major barriers to effective anemia programming include weak delivery systems, lack of data or poor use of data, lack of financial and human resources, and poor coordination. Systems strengthening and implementation research approaches are needed to address critical gaps, explore promising platforms, and identify solutions to persistent barriers to high intervention coverage. Immediate priorities are to close the gap between access to service delivery platforms and coverage of anemia interventions, reduce subnational coverage disparities, and improve the collection and use of data to inform anemia strategies and programming.

Contextual determinants of mass drug administration performance: Modelling fourteen years of lymphatic filariasis treatments in West Africa

BACKGROUND

Effective mass drug administration (MDA) is the cornerstone in the elimination of lymphatic filariasis (LF) and a critical component in combatting all neglected tropical diseases for which preventative chemotherapy is recommended (PC-NTDs). Despite its importance, MDA coverage, however defined, is rarely investigated systematically across time and geography. Most commonly, investigations into coverage react to unsatisfactory outcomes and tend to focus on a single year and health district. Such investigations omit more macro-level influences including sociological, environmental, and programmatic factors. The USAID NTD database contains measures of performance from thousands of district-level LF MDA campaigns across 14 years and 10 West African countries. Specifically, performance was measured as an MDA's epidemiological coverage, calculated as persons treated divided by persons at risk. This analysis aims to explain MDA coverage across time and geography in West Africa using sociological, environmental, and programmatic factors.

METHODOLOGY

The analysis links epidemiological coverage data from 3,880 LF MDAs with contextual, non-NTD data via location (each MDA was specific to a health district) and time (MDA month, year). Contextual data included rainfall, temperature, violence or social unrest, COVID-19, the 2014 Ebola outbreak, road access/isolation, population density, observance of Ramadan, and the number of previously completed MDAs.

PRINCIPAL FINDINGS

We fit a hierarchical linear regression model with coverage as the dependent variable and performed sensitivity analyses to confirm the selection of the explanatory factors. Above average rainfall, COVID-19, Ebola, violence and social unrest were all significantly associated with lower coverage. Years of prior experience in a district and above average temperature were significantly associated with higher coverage.

CONCLUSIONS/SIGNIFICANCE

These generalized and context-focused findings supplement current literature on coverage dynamics and MDA performance. Findings may be used to quantify typically anecdotal considerations in MDA planning. The model and methodology are offered as a tool for further investigation.

Reconciling Egg- and Antigen-Based Estimates of Schistosoma mansoni Clearance and Reinfection: A Modeling Study

BACKGROUND

Despite decades of interventions, 240 million people have schistosomiasis. Infections cannot be directly observed, and egg-based Kato-Katz thick smears lack sensitivity, affected treatment efficacy and reinfection rate estimates. The point-of-care circulating cathodic antigen (referred to from here as POC-CCA+) test is advocated as an improvement on the Kato-Katz method, but improved estimates are limited by ambiguities in the interpretation of trace results.

METHOD

We collected repeated Kato-Katz egg counts from 210 school-aged children and scored POC-CCA tests according to the manufacturer's guidelines (referred to from here as POC-CCA+) and the externally developed G score. We used hidden Markov models parameterized with Kato-Katz; Kato-Katz and POC-CCA+; and Kato-Katz and G-Scores, inferring latent clearance and reinfection probabilities at four timepoints over six-months through a more formal statistical reconciliation of these diagnostics than previously conducted. Our approach required minimal but robust assumptions regarding trace interpretations.

RESULTS

Antigen-based models estimated higher infection prevalence across all timepoints compared with the Kato-Katz model, corresponding to lower clearance and higher reinfection estimates. Specifically, pre-treatment prevalence estimates were 85% (Kato-Katz; 95% CI: 79%-92%), 99% (POC-CCA+; 97%-100%) and 98% (G-Score; 95%-100%). Post-treatment, 93% (Kato-Katz; 88%-96%), 72% (POC-CCA+; 64%-79%) and 65% (G-Score; 57%-73%) of those infected were estimated to clear infection. Of those who cleared infection, 35% (Kato-Katz; 27%-42%), 51% (POC-CCA+; 41%-62%) and 44% (G-Score; 33%-55%) were estimated to have been reinfected by 9-weeks.

CONCLUSIONS

Treatment impact was shorter-lived than Kato-Katz-based estimates alone suggested, with lower clearance and rapid reinfection. At 3 weeks after treatment, longer-term clearance dynamics are captured. At 9 weeks after treatment, reinfection was captured, but failed clearance could not be distinguished from rapid reinfection. Therefore, frequent sampling is required to understand these important epidemiological dynamics.

Effects of deworming medication on anaemia among children aged 6-59 months in sub-Saharan Africa

BACKGROUND

Despite the limited knowledge regarding the effects of deworming medication (DM) on nutritional indicators in sub-Saharan Africa (SSA), deworming programmes continue to be implemented in resource-limited countries. Therefore, the current study aimed to examine the effects of DM on anaemia among children aged 6-59 months in SSA.

METHODS

The analysis was performed using data obtained from 17 demographic and health surveys (DHSs) conducted in SSA. Children were considered to be anaemic if their haemoglobin (Hb) concentration was less than 11.0 g/dl, adjusting for altitude. To account for both multiple measures at the cluster level and the clustering of children within the same country, generalized linear mixed models were used to analyse the anaemia outcomes in 50,075 children aged 6-59 months.

RESULTS

Overall, anaemia was reported in 61.8% of the children, and their median Hb concentration was 10.5 g/dl (interquartile range 9.4-11.5). The prevalence of anaemia ranged from 34.5% in Rwanda to 81.1% in Mali. Multivariate analyses showed that children who did not receive DM had increased odds of being anaemic (adjusted odds ratio [aOR]: 1.11; 95% confidence interval [CI] 1.07-1.16).

CONCLUSIONS

The current study revealed that DM can decrease the risk of anaemia among preschool-age children (pre-SAC) in SSA. Thus, tailored public health programmes aimed at reducing childhood anaemia need to consider deworming. However, longitudinal studies are needed to validate the association that has been reported in this cross-sectional study.

Ethical dimensions of neglected tropical disease programming

The global movement to control and eliminate neglected tropical diseases (NTDs) is grounded in an ethic of social justice, solidarity and health equity. NTD programmes deliver significant health benefits in socially complex environments characterized by poverty and economic disparity. We used two ethics frameworks—principlism and Upshur's public health framework—to examine ethical challenges faced by NTD programmes. They include management of serious adverse reactions associated with preventive chemotherapy, centralization of decision-making, ‘opt-out’ policies for school-based deworming, incomplete evidence for ‘pro-poor’ impact and persistent inequities in global partnerships. NTD programmes must actively address ethical challenges while pursuing global health goals.

Deworming Coverage and its Predictors among Ethiopian Children Aged 24 to 59 Months: Further Analysis of EDHS 2016 Data Set

Intestinal parasitic infections are the major public health problem globally, mostly in developing countries. World Health Organization recommends deworming to all at-risk people living in endemic areas as a prevention or intervention strategy. Therefore this study aimed to assess the deworming coverage and its predictors among Ethiopian children aged 24-59 months. The study analyzed retrospectively cross-sectional data on a weighted sample of 5,948 children aged 24-59 months nested within 645 clusters after extracting from the Ethiopian Demographic health survey. Bivariable and multivariable logistic regression was employed to assess the association of variables. Predictors at p-value < 0.25 were entered into the multivariable logistic regression model, and statistical significance was declared at P-value < 0.05. In this study, the prevalence of maternal reported deworming supplements among children aged 24-59 months was 15.1%. Predictive variables significantly associated with deworming supplementation include maternal media exposure, maternal control of household healthcare decisions, institutional healthcare delivery, and child vitamin-A supplementation. Having history of a diarrheal disease, maternal and paternal education, and family size were also statistically significant predictors of deworming supplements. Therefore, deworming supplementation among children is low. Maternal education and employment, paternal education, family size, decision-making process, maternal media exposure, place of delivery, vitamin-A supplementation, and a having history of diarrhea were predictors of deworming supplements. Multifaceted interventions aimed at those predictors should be given emphasis.

High-resolution age-specific mapping of the two-week illness prevalence rate based on the National Health Services Survey and geostatistical analysis: a case study in Guangdong province, China

BACKGROUND

The two-week illness prevalence rate is an important and comparable indicator of health service needs. High-spatial-resolution, age-specific risk mapping of this indicator can provide valuable information for health resource allocation. The age-prevalence relationships may be different among areas of the study region, but previous geostatistical models usually ignored the spatial-age interaction.

METHODS

We took Guangdong province, the province with the largest population and economy in China, as a study case. We collected two-week illness data and other potential influencing predictors from the fifth National Health Services Survey in 2013 and other open-access databases. Bayesian geostatistical binary regression models were developed with spatial-age structured random effect, based on which, high-resolution, age-specific two-week illness prevalence rates, as well as number of people reporting two-week illness, were estimated. The equality of health resource distribution was further evaluated based on the two-week illness mapping results and the health supply data.

RESULTS

The map across all age groups revealed that the highest risk was concentrated in the central (i.e., Pearl River Delta) and northern regions of the province. These areas had a two-week illness prevalence > 25.0%, compared with 10.0-20.0% in other areas. Age-specific maps revealed significant differences in prevalence between age groups, and the age-prevalence relationships also differed across locations. In most areas, the prevalence rates decrease from age 0 to age 20, and then increase gradually. Overall, the estimated age- and population-adjusted prevalence was 16.5% [95% Bayesian credible interval (BCI): 14.5-18.6%], and the estimated total number of people reporting illness within the two-week period was 17.5 million (95% BCI: 15.5-19.8 million) in Guangdong Province. The Lorenz curve and the Gini coefficient (resulted in 0.3526) showed a moderate level of inequality in health resource distribution.

CONCLUSIONS

We developed a Bayesian geostatistical modeling framework with spatial-age structured effect to produce age-specific, high-resolution maps of the two-week illness prevalence rate and the numbers of people reporting two-week illness in Guangdong province. The methodology developed in this study can be generalized to other global regions with available relevant survey data. The mapping results will support plans for health resource allocation.

Routine deworming during antenatal care decreases risk of neonatal mortality and low birthweight: A retrospective cohort of survey data

BACKGROUND

Soil transmitted helminths (STH) are a common infection among pregnant women in areas with poor access to sanitation. Deworming medications are cheap and safe; however, the health benefit of deworming during pregnancy is not clear.

METHODS / PRINCIPAL FINDINGS

We created a retrospective cohort of more than 800,000 births from 95 Demographic and Health Survey datasets to estimate the impact of deworming medicine during routine antenatal care (ANC) on neonatal mortality and low birthweight. We first matched births on the probability of receiving deworming during ANC. We then modeled the birth outcomes with the matched group as a random intercept to estimate the effect of deworming during antenatal care after accounting for various risk factors. We also tested for effect modification of soil transmitted helminth prevalence on the impact of deworming during ANC. Receipt of deworming medication during ANC was associated with a 14% reduction in the risk of neonatal mortality (95% confidence interval = 10-17%, n = 797,772 births), with no difference between high and low transmission countries. In low transmission countries, we found an 11% reduction in the odds of low birth weight (95% confidence interval = 8-13%) for women receiving deworming medicine, and in high transmission countries, we found a 2% reduction in the odds of low birthweight (95% confidence interval = 0-5%).

CONCLUSIONS / SIGNIFICANCE

These results suggest a substantial health benefit for deworming during ANC that may be even greater in countries with low STH transmission.

Effectiveness of Deworming with Single-Dose Albendazole for Preschool-Aged Children in the Dominican Republic

Background. The World Health Organization recommends biannual deworming with single-dose albendazole for all children over 1 year in regions where soil-transmitted helminths (STH) are endemic. There are limited data from the Dominican Republic (DR) on the effectiveness of deworming programs. Methods. Between January and June 2019, we enrolled 63 preschool-aged children at a community clinic in the DR. Participants received albendazole at enrollment. Stool samples were collected and examined for parasites at enrollment, 2 to 4 and 12 to 16 weeks post-albendazole. Caregivers were surveyed on home hygiene practices and children’s symptoms. Findings. At enrollment, 1 or more parasites were noted in 89% of samples. Ascaris lumbricoides (68%) was the most common species, followed by Entamoeba histolytica (35%) and Giardia intestinalis (8%). Two-to-four weeks post-albendazole, fewer than half of those with A. lumbricoides infections at baseline had cleared the infection. STH symptoms significantly improved between enrollment and 2 to 4 weeks. By 12 to 16 weeks after treatment, A. lumbricoides infections were as high as baseline. Interpretation. Although limited by size and available technology, our study contributes data on STH in the DR. Single-dose deworming with albendazole did not reduce Ascaris lumbricoides infections in our sample. As STH are the most common neglected tropical diseases and negatively impact children’s health globally, further studies on both effective deworming programs and interventions to prevent STH are needed.

Novel transdisciplinary methodology for cross-sectional analysis of snakebite epidemiology at national scale

BACKGROUND

Worldwide, it is estimated that snakes bite 4.5-5.4 million people annually, 2.7 million of which are envenomed, and 81,000-138,000 die. The World Health Organization reported these estimates and recognized the scarcity of large-scale, community-based, epidemiological data. In this context, we developed the "Snake-Byte" project that aims at (i) quantifying and mapping the impact of snakebite on human and animal health, and on livelihoods, (ii) developing predictive models for medical, ecological and economic indicators, and (iii) analyzing geographic accessibility to healthcare. This paper exclusively describes the methodology we developed to collect large-scale primary data on snakebite in humans and animals in two hyper-endemic countries, Cameroon and Nepal.

METHODOLOGY/PRINCIPAL FINDINGS

We compared available methods on snakebite epidemiology and on multi-cluster survey development. Then, in line with those findings, we developed an original study methodology based on a multi-cluster random survey, enhanced by geospatial, One Health, and health economics components. Using a minimum hypothesized snakebite national incidence of 100/100,000/year and optimizing design effect, confidence level, and non-response margin, we calculated a sample of 61,000 people per country. This represented 11,700 households in Cameroon and 13,800 in Nepal. The random selection with probability proportional to size generated 250 clusters from all Cameroonian regions and all Nepalese Terai districts. Our household selection methodology combined spatial randomization and selection via high-resolution satellite images. After ethical approval in Switerland (CCER), Nepal (BPKIHS), and Cameroon (CNERSH), and informed written consent, our e-questionnaires included geolocated baseline demographic and socio-economic characteristics, snakebite clinical features and outcomes, healthcare expenditure, animal ownership, animal outcomes, snake identification, and service accessibility.

CONCLUSIONS/SIGNIFICANCE

This novel transdisciplinary survey methodology was subsequently used to collect countrywide snakebite envenoming data in Nepal and Cameroon. District-level incidence data should help health authorities to channel antivenom and healthcare allocation. This methodology, or parts thereof, could be easily adapted to other countries and to other Neglected Tropical Diseases.

Environmental risk assessment of the anthelmintic albendazole in Eastern Africa, based on a systematic review

This study performs an environmental risk assessment (ERA) of the anthelmintic medicine albendazole (ABZ) in the eastern African region. A systematic literature search strategy was applied to obtain quantitative information on the physicochemical characteristics, the metabolization-fate, the ecotoxicity and the environmental occurrence in different countries worldwide serving as model regions. In addition, insilico tools were employed to obtain data on physicochemical characteristics and toxic hazards of ABZ and its metabolites. Moreover, ERA models were used to predict environmental concentrations in different compartments and compare them with the measured environmental concentrations. Finally, the environmental risk of ABZ in the eastern Africa was estimated by calculating the risk quotient (RQ), and its uncertainty estimated by Monte Carlo simulation. The predicted environmental concentrations of ABZ in surface water in the model region based on consumption (1.6-267 ng/L) were within the range of values obtained from the measured environmental concentrations of the same region (0.05-101,000 ng/L). Using these models with adapted input variables for eastern Africa, the predicted surface water concentration in that region was 19,600 ± 150 ng/L (95% CI). The calculated soil concentrations of ABZ in the model regions and the eastern Africa were found to be 0.057 ± 0.0 μg/kg and 0.022 ± 0.0 μg/kg, respectively. The environmental risk expressed as risk quotient of ABZ in eastern Africa estimated for the aquatic compartment (146 ± 1) indicated a significant environmental risk calling on appropriate actions from the competent authorities to reduce this risk in this region.

Comparison of World Health Organization and Demographic and Health Surveys data to estimate sub-national deworming coverage in pre-school aged children

BACKGROUND

The key metric for monitoring the progress of deworming programs in controlling soil-transmitted helminthiasis (STH) is national drug coverage reported to the World Health Organization (WHO). There is increased interest in utilizing geographically-disaggregated data to estimate sub-national deworming coverage and equity, as well as gender parity. The Demographic and Health Surveys (DHS) offer a potential source of sub-national data. This study aimed to compare deworming coverage routinely reported to WHO and estimated by DHS in pre-school aged children to inform global STH measurement and evaluation.

METHODOLOGY

We compared sub-national deworming coverage in pre-school aged children reported to WHO and estimated by DHS aligned geospatially and temporally. We included data from Burundi (2016-2017), Myanmar (2015-2016), and the Philippines (2017) based on data availability. WHO provided data on the date and sub-national coverage per mass drug administration reported by Ministries of Health. DHS included maternally-reported deworming status within the past 6 months for each child surveyed. We estimated differences in sub-national deworming coverage using WHO and DHS data, and performed sensitivity analyses.

PRINCIPAL FINDINGS

We compared data on pre-school aged children from 13 of 18 districts in Burundi (N = 6,835 in DHS), 11 of 15 districts in Myanmar (N = 1,462 in DHS) and 16 of 17 districts in the Philippines (N = 7,594 in DHS) following data exclusion. The national deworming coverages estimated by DHS in Burundi, Myanmar, and the Philippines were 75.5% (95% CI: 73.7%-77.7%), 47.0% (95% CI: 42.7%-51.3%), and 48.0% (95% CI: 46.0%-50.0%), respectively. The national deworming coverages reported by WHO in Burundi, Myanmar, and the Philippines were 80.1%, 93.6% and 75.7%, respectively. The mean absolute differences in district-level coverage reported to WHO and estimated by DHS in Burundi, Myanmar, and the Philippines were 9.5%, 41.5%, and 24.6%, respectively. Across countries, coverage reported to WHO was frequently higher than DHS estimates (32 of 40 districts). National deworming coverage from DHS estimates were similar by gender within countries.

CONCLUSIONS AND SIGNIFICANCE

Agreement of deworming coverage reported to WHO and estimated by DHS data was heterogeneous across countries, varying from broadly compatible in Burundi to largely discrepant in Myanmar. DHS data could complement deworming data reported to WHO to improve data monitoring practices and serve as an independent sub-national source of coverage data.

Missed opportunity of deworming a Maasai boy from nomadic family leading to life threatening intestinal obstruction

Mass deworming against soil-transmitted helminthiasis, including Ascaris lumbricoides (AL), is one of the largest public health interventions in low- and middle-income countries. The prevalence of A. lumbricoides in Tanzania is 6.8%. We present a 3-year-old male of a known Tanzanian nomadic tribe (Masaai tribe) with history of missed deworming, who was brought to the emergency department with a 3-day history of constipation, nonprojectile, bilious vomiting, generalized abdominal distension and pain.

He was diagnosed with intestinal obstruction by the use of a plain abdominal X-ray, which revealed marked gaseous distension of the stomach and bowels without significant air-fluid levels. He was initially treated with intravenous ceftriaxone 50 mg/kg, metronidazole 15 mg/kg and acetaminophen 15 mg/kg. An explorative laparotomy was then performed. Intraoperative findings demonstrated a dense collection of A. lumbricoides worms in the gangrenous proximal jejunum and duodenum. Thorough abdominal lavage was carried out and abdomen was closed.

Comparison of multi-parallel qPCR and double-slide Kato-Katz for detection of soil-transmitted helminth infection among children in rural Bangladesh

There is growing interest in local elimination of soil-transmitted helminth (STH) infection in endemic settings. In such settings, highly sensitive diagnostics are needed to detect STH infection. We compared double-slide Kato-Katz, the most commonly used copromicroscopic detection method, to multi-parallel quantitative polymerase chain reaction (qPCR) in 2,799 stool samples from children aged 2–12 years in a setting in rural Bangladesh with predominantly low STH infection intensity. We estimated the sensitivity and specificity of each diagnostic using Bayesian latent class analysis. Compared to double-slide Kato-Katz, STH prevalence using qPCR was almost 3-fold higher for hookworm species and nearly 2-fold higher for Trichuris trichiura. Ascaris lumbricoides prevalence was lower using qPCR, and 26% of samples classified as A. lumbricoides positive by Kato-Katz were negative by qPCR. Amplicon sequencing of the 18S rDNA from 10 samples confirmed that A. lumbricoides was absent in samples classified as positive by Kato-Katz and negative by qPCR. The sensitivity of Kato-Katz was 49% for A. lumbricoides, 32% for hookworm, and 52% for T. trichiura; the sensitivity of qPCR was 79% for A. lumbricoides, 93% for hookworm, and 90% for T. trichiura. Specificity was ≥ 97% for both tests for all STH except for Kato-Katz for A. lumbricoides (specificity = 68%). There were moderate negative, monotonic correlations between qPCR cycle quantification values and eggs per gram quantified by Kato-Katz. While it is widely assumed that double-slide Kato-Katz has few false positives, our results indicate otherwise and highlight inherent limitations of the Kato-Katz technique. qPCR had higher sensitivity than Kato-Katz in this low intensity infection setting.

Soil-transmitted helminth infections (STH) (e.g., Ascaris, hookworm, Trichuris) contribute to a large burden of disease among children in low- and middle-income countries. There is increasing interest in implementing large-scale deworming programs to eliminate STH in certain settings. Efforts to monitor whether local elimination has occurred require sensitive diagnostic tests that will not miss positive cases. Kato-Katz, a microscopy-based diagnostic test, has commonly been used to identify STH eggs in stool, but in settings where infection intensity is low, this method frequently misses positive samples because it requires visual identification of small numbers of eggs, and hookworm eggs may degrade prior to visualization. Quantitative polymerase chain reaction (qPCR) is a molecular diagnostic method for detecting STH. It may detect more low intensity infections than Kato-Katz because it identifies STH DNA in stool; DNA can be detected in very small quantities and is less likely to degrade than STH ova. Thus, qPCR is likely to be more accurate than Kato-Katz. This study compared the performance of double-slide Kato-Katz and qPCR using 2,799 stool samples from children aged 2–12 years in a setting in rural Bangladesh with predominantly low STH infection intensity. qPCR was more sensitive than Kato-Katz for hookworm and Trichuris infections. 26% of samples were classified as Ascaris positive by Kato-Katz and negative by qPCR. DNA sequencing of 10 samples confirmed that Ascaris was absent in samples classified as positive by Kato-Katz and negative by qPCR. We conclude that Kato-Katz likely produced false positive results for Ascaris and that qPCR had a higher sensitivity than double-slide Kato-Katz in this low infection intensity setting.