The American Journal of Tropical Medicine and Hygiene - Current Issue

Postexposure prophylaxis using artemisinin-based combination therapy (ACT) was prescribed to a malaria-naive nurse who experienced an injury with a hollow needle previously used on a patient admitted for severe imported Plasmodium falciparum malaria (blood parasitemia 10.8%). Artemether–lumefantrine, four tablets twice daily for 3 days, was started 12 hours after exposure, and no side effects were reported. During the six following months, she only developed one episode of fever that was associated with pyelonephritis. Biological follow-up, based on blood smears, molecular biology, and serology, did not evidence P. falciparum malaria. This case suggests that ACT can prevent occupational P. falciparum malaria following needle-stick injury. We found evidence of only one other unpublished similar case where a Turkish resident doctor did not develop malaria after postexposure prophylaxis using ACT. Such a prophylaxis could be prescribed not only in case of occupational exposure to Plasmodium spp. in nonvector-borne laboratory-acquired infections but also following blood exposure in healthcare setting.

Malaria and malnutrition remain primary causes of morbidity and mortality among children younger than 5 years in Africa. Studies investigating the association between malnutrition and subsequent malaria outcomes are inconsistent. We studied the effects of malnutrition on incidence and prevalence of malaria parasitemia in data from a cohort studied in the 1990s. Data came from the Asembo Bay cohort study, which collected malaria and health information on children from 1992 to 1996 in western Kenya. Infants were enrolled at birth and followed up until loss to follow-up, death, end of study, or 5 years old. Anthropometric measures and blood specimens were obtained monthly. Nutritional exposures included categorized Z-scores for height-for-age, weight-for-age, and weight-for-height. Febrile parasitemia and afebrile parasitemia were assessed with thick and thin blood films. Multiply imputed and weighted multinomial generalized estimating equation models estimated odds ratios (OR) for the association between exposures and outcomes. The sample included 1,182 children aged 0–30 months who contributed 18,028 follow-up visits. There was no significant association between malnutrition and either incident febrile parasitemia or prevalent febrile parasitemia. Prevalence ORs for afebrile parasitemia increased from 1.07 (95% CI: 0.89, 1.29) to 1.35 (1.03, 1.76) as stunting severity increased from mild to severe, and from 1.16 (1.02, 1.33) to 1.35 (1.09, 1.66) as underweight increased from mild to moderate. Stunting and underweight did not show a significant association with subsequent febrile parasitemia infections, but they did show a modest association with subsequent afebrile parasitemia. Consideration should be given to testing malnourished children for malaria, even if they present without fever.

The occurrence of malaria resurgences could threaten progress toward elimination of the disease. This study investigated the impact of repeated renewal of long-lasting insecticide-treated net (LLIN) universal coverage on malaria resurgence over a period of 10 years of net implementation in Dielmo (Senegal). A longitudinal study was carried out in Dielmo between August 2007 and July 2018. In July 2008, LLINs were offered to all villagers through universal campaign distribution which was renewed in July 2011, August 2014, and May 2016. Malaria cases were treated with artemisinin-based combination therapy. Two resurgences of malaria occurred during the 10 years in which LLINs have been in use. Since the third renewal of the nets, malaria decreased significantly compared with the first year the nets were implemented (adjusted incidence rate ratio) (95% CI) = 0.35 (0.15–0.85), during the ninth year after net implementation). During the tenth year of net implementation, no cases of malaria were observed among the study population. The use of nets increased significantly after the third time the nets were renewed when compared with the year after the first and the second times the nets were renewed (P < 0.001). The third renewal of nets, which took place after 2 years instead of 3 years together with a higher use of LLINs especially among the young, probably prevented the occurrence of a third malaria upsurge in this village.

Delayed parasite clearance time observed in Southeast Asia provided the first evidence of Plasmodium falciparum resistance to artemisinins. The ex vivo ring-stage survival assay (RSA) mimics parasite exposure to pharmacologically relevant artemisinin concentrations. Mutations in the C-terminal propeller domain of the putative kelch protein Pf3D7_1343700 (K13) are associated with artemisinin resistance. Variations in the pfmdr1 gene are associated with reduced susceptibility to the artemisinin partner drugs mefloquine (MQ) and lumefantrine (LF). To clarify the unknown landscape of artemisinin resistance in Colombia, 71 patients with uncomplicated P. falciparum malaria were enrolled in a non-randomized observational study in three endemic localities in 2014–2015. Each patient’s parasite isolate was assessed for ex vivo RSA, K13-propeller mutations, pfmdr1 copy number, and pfmdr1 mutations at codons 86, 184, 1034, 1042, and 1246, associated with reduced susceptibility, and 50% inhibitory concentration (IC50) for other antimalarial drugs. Ex vivo RSAs were successful in 56% (40/71) of samples, and nine isolates showed survival rates > 1%. All isolates had wild-type K13-propeller sequences. All isolates harbored either of two pfmdr1 haplotypes, NFSDD (79.3%) and NFSDY (20.7%), and 7.1% of isolates had > 1 pfmdr1 gene. In vitro IC50 assays showed that variable proportions of isolates had decreased susceptibility to chloroquine (52.4%, > 100 nM), amodiaquine (31.2%, > 30 nM), MQ (34.3%, > 30 nM), and LF (3.2%, > 10 nM). In this study, we report ex vivo RSA and K13 data on P. falciparum isolates from Colombia. The identification of isolates with increased ex vivo RSA rates in the absence of K13-propeller mutations and no positivity at day three requires further investigation.

Artemisinin combination therapies are the current frontline therapy for falciparum malaria. Artemisinin is activated by heme iron, and the consequent production of reactive oxygen species and carbon-centered radicals results in rapid parasite clearance. Red blood cells (RBCs) from anemic iron-deficient individuals have decreased levels of heme, and such deficiencies are highly prevalent among children and pregnant women in malaria-endemic countries. We, therefore, investigated the possibility that host anemia could impair artemisinin activity and alter the drug sensitivity of artemisinin-resistant strains of Plasmodium falciparum. We collected RBCs from anemic (n = 35) and nonanemic (n = 11) Gambian children between the ages of 2 and 24 months. Parasites grown in RBCs from both groups were assessed in vitro using the ring-stage survival assay with artemisinin-resistant and artemisinin-sensitive strains of P. falciparum. No differences were found in artemisinin sensitivity (P > 0.05), and there was no correlation between artemisinin activity and host hemoglobin levels. Standard antimalarial drug activity assays for representatives of the major classes of antimalarial drugs found no differences in the IC50 values against P. falciparum between anemic and nonanemic RBCs. We conclude that host anemia does not influence artemisinin activity.

The control of malaria, in terms of drug resistance, remains a significant global challenge, with Bangladesh, a malaria-endemic country, being no exception. The aim of this study was to explore antimalarial resistance in Bangladesh by molecular analysis of Plasmodium falciparum chloroquine resistance transporter (pfcrt) and P. falciparum multidrug resistance transporter 1 (pfmdr1) genetic markers of P. falciparum. Samples were obtained from uncomplicated malaria patients between 2009 and 2014 from six malaria-endemic districts. Based on parasite transmission intensity, the endemic districts were divided into high-transmission (Chittagong Hill Tracts [CHT]) and low-transmission (non-CHT) regions. Falciparum malaria-positive isolates were genotyped for K76T of the pfcrt gene, and N86Y and Y184F of the pfmdr1 gene: in total, 262 P. falciparum clinical isolates were analyzed. In CHT areas, the prevalence of polymorphisms was 70.6% for 76T, 14.4% for 86Y, and 7.8% for 184F. In non-CHT areas, 76T and 86Y mutations were found in 78.0% and 19.5% of the samples, respectively, whereas no 184F mutations were observed. We compared our data with previous similar molecular observations, which shows a significant decrease in pfcrt 76T mutation prevalence. No pfmdr1 amplification was observed in any of the samples suggesting an unaltered susceptibility to amino alcohol drugs such as mefloquine and lumefantrine. This study provides an updated assessment of the current status of pfcrt and pfmdr1 gene mutations in Bangladesh, and suggests there is persistent high prevalence of markers of resistance to aminoquinoline drugs.

Plasmodium falciparum sporozoite (PfSPZ) Vaccine (radiation-attenuated, aseptic, purified, cryopreserved PfSPZ) and PfSPZ-CVac (infectious, aseptic, purified, cryopreserved PfSPZ administered to subjects taking weekly chloroquine chemoprophylaxis) have shown vaccine efficacies (VEs) of 100% against homologous controlled human malaria infection (CHMI) in nonimmune adults. Plasmodium falciparum sporozoite-CVac has never been assessed against CHMI in African vaccinees. We assessed the safety, immunogenicity, and VE against homologous CHMI of three doses of 2.7 × 106 PfSPZ of PfSPZ Vaccine at 8-week intervals and three doses of 1.0 × 105 PfSPZ of PfSPZ-CVac at 4-week intervals with each arm randomized, double-blind, placebo-controlled, and conducted in parallel. There were no differences in solicited adverse events between vaccinees and normal saline controls, or between PfSPZ Vaccine and PfSPZ-CVac recipients during the 6 days after administration of investigational product. However, from days 7–13, PfSPZ-CVac recipients had significantly more AEs, probably because of Pf parasitemia. Antibody responses were 2.9 times higher in PfSPZ Vaccine recipients than PfSPZ-CVac recipients at time of CHMI. Vaccine efficacy at a median of 14 weeks after last PfSPZ-CVac dose was 55% (8 of 13, P = 0.051) and at a median of 15 weeks after last PfSPZ Vaccine dose was 27% (5 of 15, P = 0.32). The higher VE in PfSPZ-CVac recipients of 55% with a 27-fold lower dose was likely a result of later stage parasite maturation in the liver, leading to induction of cellular immunity against a greater quantity and broader array of antigens.

Village health workers (VHWs) in Bugoye subcounty, Uganda, provide integrated community case management (iCCM) care to children younger than 5 years for malaria, pneumonia, and diarrhea. We assessed the longevity of VHWs’ skills in performing and reading malaria rapid diagnostic tests (RDTs) 4 years after initial training, comparing VHWs who had completed initial iCCM training 1 year before the study with VHWs who had completed training 4 years before the study. Both groups received quarterly refresher trainings. Trained interviewers observed 36 VHWs reading six mock RDTs each and performing an RDT as part of a larger skills assessment exercise. VHWs read 97% of mock RDTs correctly; of the 36 VHWs, 86% read all six mock RDTs correctly. Most VHWs scored either 12/13 or 13/13 on the RDT checklist (39% and 36%, respectively), with 25% scoring 11/13 or lower. For reading mock RDTs, VHWs in the first group (initial training 4 years before study) read 97% of mock RDTs correctly, whereas those in the second group (initial training 1 year before study) read 96% of mock RDTs correctly; the first group had a mean of 5.83 RDTs read correctly, compared with 5.77 RDTs read correctly in the second group (P = 0.83). For performing an RDT, the first group completed a mean of 12.0 steps correctly, compared with a mean of 12.2 correct steps in the second group (P = 0.60). Overall, VHWs demonstrated proficiency in reading RDTs accurately and performing RDTs according to protocol at least 4 years after initial iCCM training.

Spinal sparganosis of the cauda equina has been rarely reported. A 54-year-old man presented at the hospital after having experienced lower back pain for 10 months, progressive weakness and numbness of the left leg for 4 months, and urinary incontinence for 3 weeks. Magnetic resonance imaging of the lumbosacral spine revealed a heterogeneous enhancing mass at the T12-S1 level. Spinal sparganosis was diagnosed by histological examination and molecular identification of the parasite in the tissue section. The patient was treated with a high dose of praziquantel because the parasitic mass was only partially removed and symptoms worsened following surgery.

Increased levels of guinea worm (GW) disease transmission among dogs in villages along the Chari River in Chad threaten the gains made by the GW Eradication Program. Infected dogs with preemergent worm blisters are difficult to proactively identify. If these dogs are not contained, blisters can burst upon submersion in water, leading to the contamination of the water supply with L1 larvae. Guinea worm antigens previously identified using sera from human dracunculiasis patients were coupled to polystyrene beads for multiplex bead assay analysis of 41 non-endemic (presumed negative) dog sera and 39 sera from GW-positive dogs from Chad. Because commercially available anti-dog IgG secondary antibodies did not perform well in the multiplex assay, dog IgGs were partially purified, and a new anti-dog IgG monoclonal antibody was developed. Using the new 4E3D9 monoclonal secondary antibody, the thioredoxin-like protein 1–glutathione-S-transferase (GST), heat shock protein (HSP1)–GST, and HSP2–GST antigen multiplex assays had sensitivities of 69–74% and specificities of 73–83%. The domain of unknown function protein 148 (DUF148)–GST antigen multiplex assay had a sensitivity of 89.7% and a specificity of 85.4%. When testing samples collected within 1 year of GW emergence (n = 20), the DUF148–GST assay had a sensitivity of 90.0% and a specificity of 97.6% with a receiver-operating characteristic area under the curve of 0.94. Using sera from two experimentally infected dogs, antibodies to GW antigens were detected within 6 months of exposure. Our results suggest that, when used to analyze paired, longitudinal samples collected 1–2 months apart, the DUF148/GST multiplex assay could identify infected dogs 4–8 months before GW emergence.

Non–plaque-induced lesions may occur on the gingiva as medical disorders or manifestations of systemic conditions. Scabies is a parasitic infection caused by Sarcoptes scabiei. Here, we present the first case of oral scabies reported in the literature located on the gingiva in a 43-year-old woman. She was admitted to the hospital complaining of an ulcerative lesion on the gingiva with unknown duration, with a suggestive diagnosis of pemphigoid. A diagnosis of scabies infestation was made based on the visualization of eggs and larvae/nymph forms. The treatment consisted of 100 mg of ivermectin (three times per day for 15 days), supplemental oral hygiene with chlorhexidine, and extensive cleaning. The follow-up was made 30 days after treatment with ivermectin. The patient did not report side effects, with skin and oral lesions completely healed. Based on this, we need to perform a thoughtful ectoscopy examination and be alert to signs that indicate unusual causes to diagnose correctly and choose the appropriate treatment.

Snakebite envenomation (SBE) is a neglected One Health issue that overwhelmingly affects people living in rural and impoverished regions of Africa and Asia. Information on SBE is scarce in Rwanda; thus, our objectives were to 1) describe the demographics of SBE patients seeking hospital care, 2) evaluate physician adherence to national treatment guidelines, and 3) assess availability of snake antivenom at hospitals in Rwanda. To achieve these goals, we obtained national data on animal bites/stings and visited every district and provincial hospital in Rwanda to obtain physical records of SBE patients treated in 2017 and 2018. Hospital pharmacies were assessed for antivenom availability. We identified snakes as the second leading cause of animal bites, after dogs, among patients who sought hospital care in 2017 and 2018. Of 363 SBE patients, the highest number of cases occurred among children (< 18 years; 32%) and young adults (18–30 years; 33%), females (61%), farmers (82%), and those living in Eastern Province (37%). Overall, physician adherence to treatment guidelines was 63%. Prescriptions of vitamin K and antivenom were low (4% and 13%, respectively), and only 8% of hospital pharmacies had antivenom in stock throughout the study period. The antivenom stocked was an Indian generic suited for Asian snakes. This minimum estimate of hospitalization cases does not include individuals who died in communities or sought care outside the formal sector. Our study highlights the need to map incidence, risk factors, and patient experiences to mitigate human–snake conflicts and improve patient outcomes.

Protobothrops mucrosquamatus is one of the common venomous snakes in Southeast Asia. This retrospective cohort study conducted in six medical institutions in Taiwan aimed to obtain information on the optimal management strategies for P. mucrosquamatus snakebite envenomation. Data were extracted from the Chang Gung Research Database from January 2006 to December 2016. The association between early antivenom administration and patient demographics, pain requiring treatment with analgesic injections, and hospital length of stay was analyzed. A total of 195 patients were enrolled; 130 were administered antivenom within 1 hour after emergency department arrival (early group), whereas 65 were treated later than 1 hour after arrival (late group). No in-hospital mortality was identified. The difference in surgical intervention rates between the early and late groups was statistically insignificant (P = 0.417). Compared with the early group, the late group showed a higher rate of antivenom skin test performance (46.9% versus 63.1%, respectively, P = 0.033), longer hospital stay (42 ± 62 hours versus 99 ± 70 hours, respectively, P = 0.016), and higher rate of incidences of pain requiring treatment with analgesic injections (29.2% versus 46.2%, respectively, P = 0.019). After adjusting for confounding factors, early antivenom administration was associated with decreased pain requiring treatment with analgesic injections (adjusted odds ratio: 0.51, 95% CI: 0.260–0.985). Antivenom administration within 1 hour of arrival was associated with a decreased likelihood of experiencing pain and hospital length of stay in patients with P. mucrosquamatus snakebites. Antivenom skin testing was associated with delays in antivenom administration.

The Swat district, a conflict-hit territory due to Taliban militancy, had a damaged local health infrastructure. Animal-bite injuries leading to rabies is one of the major health concerns in developing countries, especially within conflict zones. The current prospective epidemiological study was conducted to estimate the cumulative incidence of animal-bite injuries, to summarize characteristics of bite victims and biting animals, and to collect information about post-exposure prophylaxis (PEP) practices in Swat district, Pakistan, during 2014. A questionnaire was designed to collect data about the sociodemography of the patients, bite incident situation (provoked or unprovoked), injury pattern, animal type, PEP, and vaccination. Descriptive analyses were conducted using bar graphs, frequency tables, and chi-square tests were used to determine associations. The cumulative incidence of animal-bite injuries was 39 per 100,000 people during the study period (May–August 2014). The majority of incidents were reported from rural regions (77.7%) and were males (76.6%) younger than 10 years (37.3%). Dogs were the most frequent biting animal (86.8%) followed by rats (4.7%). About 77.7% patients washed their wound before arrival at hospital. After an eclipse phase of 10 days, 44 (10.1%) animals developed sign of rabies. The current study has highlighted a topic of interest for health, education, veterinary, and local government policy makers regarding prevention of animal bites, benefits of PEP, vaccination of human and domestic animals, control of stray dogs, and eradication of rabies in developing countries with damaged healthcare structures.

Access to safe water and basic sanitation and hygiene facilities (WASH) are important for childhood health globally. However, inequalities in WASH access persist, and local governments need to better understand the potential impact of scaling up WASH services on childhood health. Using 2011 Peru Demographic and Health Survey data as a case study, we applied a modified substitution estimator approach to assess the impact of scaling up access (20–100%) to WASH on diarrhea prevalence among children < 5 years. The modified substitution estimator approach can help identify population subgroups or areas where WASH interventions and sustained implementation could be most beneficial and reduce existing disparities. Using findings from a recent meta-analysis and computing bootstrapped estimates and 95% CIs, we examined inequalities in the effect of WASH on self-reported diarrhea by urbanicity, maternal education level, household wealth, and district of residence. Increasing access (100% change) to improved water sources, sanitation, and hygiene facilities reduced population-level prevalence of childhood diarrhea by 8.2% (95% CI: 4.1, 12.3), 5.5% (95% CI: 0.7, 9.8), and 5.2% (95% CI: 2.2, 8.1), respectively. In stratified analyses, increased access to improved water sources and hygiene facilities was associated with decreased prevalence of diarrhea, with the largest reduction in rural areas and households with lower maternal education and lower wealth. Our findings suggest targeted WASH implementation in Peru is needed in rural areas and among lower socioeconomic-status households. In addition, even low levels of change in overall WASH access may decrease diarrhea prevalence.

The persistence and pervasiveness of growth stunting in low- and middle-income countries spur reexamination of disease transmission pathways related to water, sanitation, and hygiene. Animal feces constitute a more important reservoir of enteric pathogens in homes in low-income countries than previously recognized, and exploratory object mouthing and direct ingestion of soil and animal feces represent underexplored exposure pathways. The effectiveness, adoption, constraints, and scale-up potential of measures for reducing infant and young children’s exposure to fecal pathogens are recently beginning to be systematically explored. This mixed methods study tested the feasibility and appeal of using playpens to establish a hygienic “safe zone” for infants in rural Ethiopia. We conducted home trials of three playpen designs, including two models made from locally available materials through user-centered design. After using playpens for several weeks, caregivers reported extensive benefits, ranging from perceived safety to developmental and hygiene benefits for infants and relief from physical stress and worry for caregivers. We observed many playpens contaminated with Escherichia coli after weeks of use, though at concentrations below those of the common room floor on which infants might otherwise have played. Caregivers reported daily playpen use, but for intervals likely insufficient to protect infants from pathogen exposure affecting growth. We determine that playpens alone cannot plausibly protect infants from environmental contamination, but our results support further exploration of the potential benefits and commercial viability of scaling up use of playpens in rural, agricultural households as part of a comprehensive approach to child development and women’s empowerment.

Poor food hygiene practices, child feces not being disposed of in a latrine, child mouthing of contaminated fomites, and poor hand hygiene of caregivers have been associated with diarrheal diseases, environmental enteropathy, and impaired growth in young children. Mobile health (mHealth) programs present a low-cost approach to delivering water, sanitation, and hygiene (WASH) programs. We conducted a theory-driven and evidence-based approach to formative research and intervention development to design and pilot test a Baby WASH mHealth program targeting food hygiene, child mouthing, and child feces disposal behaviors in urban Dhaka, Bangladesh. Formative research activities included 31 semi-structured interviews, five group discussions, six mHealth workshops, and a three-phase iterative pilot study among 102 households. Findings from semi-structured interviews and group discussions indicate that caregivers of young children have relatively high awareness of the need for safer food hygiene, child mouthing, and child feces disposal practices, but are limited by existing household responsibilities and restricted access to enabling technology that would facilitate practicing recommended behaviors. The piloted Baby WASH mHealth program was well-received by households. This study presents a theory-driven and evidence-based approach for intervention development that can be implemented for the development of future WASH mHealth programs in low-resource settings.

Using previously validated microbial source tracking markers, we detected and quantified fecal contamination from avian species and avian exposure, dogs, and humans on household cooking tables and floors. The association among contamination, infrastructure, and socioeconomic covariates was assessed using simple and multiple ordinal logistic regressions. The presence of Campylobacter spp. in surface samples was linked to avian markers. Using molecular methods, animal feces were detected in 75.0% and human feces in 20.2% of 104 households. Floors were more contaminated than tables as detected by the avian marker Av4143, dog marker Bactcan, and human marker Bachum. Wood tables were consistently more contaminated than non-wood surfaces, specifically with the mitochondrial avian markers ND5 and CytB, fecal marker Av4143, and canine marker Bactcan. Final multivariable models with socioeconomic and infrastructure characteristics included as covariates indicate that detection of avian feces and avian exposure was associated with the presence of chickens, maternal age, and length of tenancy, whereas detection of human markers was associated with unimproved water source. Detection of Campylobacter in surface samples was associated with the avian fecal marker Av4143. We highlight the critical need to detect and measure the burden of animal fecal waste when evaluating household water, hygiene, and sanitation interventions, and the possibility of decreasing risk of exposure through the modification of surfaces to permit more effective household disinfection practices. Animals may be a more important source of household fecal contamination than humans in many low-resource settings, although interventions have historically focused almost exclusively on managing human waste.

Despite multiple studies demonstrating the effectiveness of household water treatment with chlorine in disinfecting water and preventing diarrhea, social marketing of this intervention in low- and middle-income countries has resulted in only modest uptake. In a cluster randomized trial in Vihiga district, western Kenya, we compared uptake of household water treatment with chlorine among six villages served by community vendors trained in standard social marketing plus education through listening (ETL), an innovative behavior change method, and six villages served by community vendors trained in standard social marketing only. Water treatment uptake, water quality, and childhood diarrhea were measured over 6 months and compared between the two groups of villages. During the 6-month period, we found no association between ETL exposure and reported and confirmed household water treatment with chlorine. In both groups (ETL and comparison), reported use of water treatment was low and did not change during our 6-month follow-up. However, persons confirmed to have chlorinated water had improved bacteriologic water quality. Study findings suggest that ETL implementation was suboptimal, which, along with unexpected changes in the supply and price of chlorine, may have prevented an accurate assessment of the potential impact of ETL on water treatment behavior. Taken together, these observations exemplify the complexities of habits, practices, attitudes, and external factors that can create challenging conditions for implementing behavioral interventions. As a consequence, in this trial, ETL had no measurable impact on water treatment behavior.

We sought to determine whether a shortened version of the 12-item Household Water Insecurity Experiences (HWISE) Scale, which measures water insecurity equivalently in low- and middle-income countries (LMICs), is valid for broad use. Using data from 9,261 households in 25 LMICs, subsets of candidate items were evaluated on their predictive accuracy, criterion validity, and sensitivity–specificity. A subset with items assessing “worry,” “changing plans,” “limited drinking water,” and “inability to wash hands” because of problems with water (range: 0–12) were highly correlated with full HWISE Scale scores (correlation coefficient: 0.949–0.980) and introduced minimal additional error (root mean square error: 2.13–2.68). Criterion validity was demonstrated, and a cut point of ≥ 4 correctly classified more than 91% of households as water secure or insecure. The brief HWISE-4 can be used in LMICs to inform decisions about how to most effectively target resources and evaluate public health interventions.