Bio


Dr. Aiemjoy is an infectious disease epidemiologist with interests in diarrheal disease, measurement, diagnostics, and sero-epidemiology. She is currently working on evaluating serological markers for Salmonella Typhi and Paratyphi infection as part of the Sero-Epidemiology and Environmental Surveillance (SEES) study in Nepal, Pakistan and Bangladesh.

Honors & Awards


  • National Institute of Health (NIH) Loan Repayment Program Award, National Institute of Allergy and Infectious Diseases (NIAID) (2019-2021)
  • Ruth L. Kirschstein National Research Service Award Individual Fellowship (F31HD088070), National Institute of Health (NIH) National Institute of Child Health and Development (NICHD) (2016-2018)
  • Travel Award, American Society of Tropical Medicine and Hygiene & The Bill and Melinda Gates Foundation (2018)
  • Dissertation Award, American Association of University Women (AAUW) (2017)
  • Research Award, ALTA Foundation (2016)
  • Award for Excellence in Teaching, UCSF Training in Clinical Research Program (2015)

Professional Education


  • Doctor of Philosophy, University of California San Francisco, Epidemiology (2018)
  • Master of Science, London School of Hygiene and Tropical Medicine, Public Health (2011)
  • Bachelor of Science, Georgetown University, Foreign Service (2010)

Stanford Advisors


Projects


  • Sero-Epidemiology and Environmental Surveillance (SEES), Stanford University (2018 - 2020)

    Location

    Kathmandu, Nepal

    Collaborators

    • Denise Garrett, PI, Sabin Vaccine Institute
  • Surveillance for Enteric Fever in Asia Project (SEAP), Stanford University (2016 - 2022)

    Location

    Kathmandu, Nepal

    Collaborators

    • Denise Garrett, Dr., Sabin Vaccine Institute
  • Integrated serologic surveillance for infectious disease transmission and vaccine-acquired immunity by fingerstick dried blood spots, Stanford University (2019 - 2021)

    Public health surveillance is notoriously siloed. A single country or region may have dozens of disease-specific control and vaccination programs operating in parallel, each with their own surveillance operations. As a consequence, there are often insufficient data concerning disease burden and vaccine coverage for most pathogens of public health importance. We propose to evaluate a novel low-cost approach to surveillance by simultaneously measuring immune response to dozens of pathogen and vaccine-acquired antigens from a single drop of blood.
    PI: Kristen Aiemjoy, MSc PhD
    Co-PI: Jason Andrews, MD

    Location

    Kathmandu, Nepal

All Publications


  • Defining Diarrhea: A Population-Based Validation Study of Caregiver-Reported Stool Consistency in the Amhara Region of Ethiopia AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE Aiennjoy, K., Aragie, S., Gebresillasie, S., Fry, D. M., Dagnew, A., Hailu, D., Chanyalew, M., Tadesse, Z., Stewart, A., Callahan, K., Freeman, M., Neuhaus, J., Arnold, B. F., Keenan, J. D. 2018; 98 (4): 1013–20

    Abstract

    Diarrhea is a leading cause of death among children aged less than five years globally. Most studies of pediatric diarrhea rely on caregiver-reported stool consistency and frequency to define the disease. Research on the validity of caregiver-reported diarrhea is sparse. We collected stool samples from 2,398 children participating in two clinical trials in the Amhara region of Ethiopia. The consistency of each stool sample was graded by the child's caregiver and two trained laboratory technicians according to an illustrated stool consistency scale. We assessed the reliability of graded stool consistency among the technicians, and then compared the caregiver's grade with the technician's grade. We also tested if the illustrated stool consistency scale could improve the validity of caregiver's report. The weighted kappa measuring the agreement between the two laboratory technicians reached 0.90 after 500 stool samples were graded. The sensitivity of caregiver-reported loose or watery stool was 15.5% (95% confidence interval [CI]: 9.7, 24.2) and the specificity was 98.4% (95% CI 97.1, 99.1). With the illustrated scale, the sensitivity was 68.5% (95% CI: 58.5, 77.1) and the specificity was 86.1% (95% CI: 79.3, 90.9). The results indicate that caregiver-reported stool consistency using the terms "loose or watery" does not accurately describe stool consistency as graded by trained laboratory technicians. Given the predominance of using caregiver-reported stool consistency to define diarrheal disease, the low sensitivity identified in this study suggests that the burden of diarrheal disease may be underestimated and intervention effects could be biased. The illustrated scale is a potential low-lost tool to improve the validity of caregiver-reported stool consistency.

    View details for DOI 10.4269/ajtmh.17-0806

    View details for Web of Science ID 000430958200010

    View details for PubMedID 29488457

    View details for PubMedCentralID PMC5928832

  • Rectal Swabs as an Alternative Sample Collection Method to Bulk Stool for the Real-Time PCR Detection of Giardia duodenalis. The American journal of tropical medicine and hygiene Maasch, J. R., Arzika, A. M., Cook, C., Lebas, E., Pilotte, N., Grant, J. R., Williams, S. A., Keenan, J. D., Lietman, T. M., Aiemjoy, K. 2020

    Abstract

    Though bulk stool remains the gold standard specimen type for enteropathogen diagnosis, rectal swabs may offer comparable sensitivity with greater ease of collection for select pathogens. This study sought to evaluate the validity and reproducibility of rectal swabs as a sample collection method for the molecular diagnosis of Giardia duodenalis. Paired rectal swab and bulk stool samples were collected from 86 children ages 0-4 years living in southwest Niger, with duplicate samples collected among a subset of 50 children. Infection was detected using a previously validated real-time PCR diagnostic targeting the small subunit ribosomal RNA gene. Giardia duodenalis was detected in 65.5% (55/84) of bulk stool samples and 44.0% (37/84) of swab samples. The kappa evaluating test agreement was 0.81 (95% CI: 0.54-1.00) among duplicate stool samples (N = 49) and 0.75 (95% CI: 0.47-1.00) among duplicate rectal swabs (N = 48). Diagnostic sensitivity was 93% (95% CI: 84-98) by bulk stool and 63% (95% CI: 49-75) by rectal swabs. When restricting to the lowest three quartiles of bulk stool quantitation cycle values (an indication of relatively high parasite load), sensitivity by rectal swabs increased to 78.0% (95% CI: 64-89, P < 0.0001). These findings suggest that rectal swabs provide less sensitive and reproducible results than bulk stool for the real-time PCR diagnosis of G. duodenalis. However, their fair sensitivity for higher parasite loads suggests that swabs may be a useful tool for detecting higher burden infections when stool collection is excessively expensive or logistically challenging.

    View details for DOI 10.4269/ajtmh.19-0909

    View details for PubMedID 32524959

  • Odour reduction interventions for simple pit latrines in rural Ethiopia: a randomized study. Transactions of the Royal Society of Tropical Medicine and Hygiene Aragie, S., Wittberg, D. M., Aiemjoy, K., Melo, J. S., Smith, M. J., Nash, S. D., Tadesse, Z., Keenan, J. D. 2020

    Abstract

    Pit latrines are promoted in resource-limited settings, but unpleasant odours may deter their use. In this study, latrines in rural Ethiopia were randomized to the addition of cooking ash, the addition of boiling water or neither. Study staff ranked odour on a 6-point scale before and approximately 24h after intervention. Following intervention, odour grades were on average 0.2 points lower (95% confidence interval [CI] 0.7 lower to 0.3 higher) in ash-treated latrines and 0.4 points lower (95% CI 0.9 lower to 0.1 higher) in boiled water-treated latrines, although the difference between the three groups was not statistically significant (p=0.21). Larger studies might detect a smaller difference.

    View details for DOI 10.1093/trstmh/traa039

    View details for PubMedID 32503041

  • Environmental Surveillance as a Tool for Identifying High-risk Settings for Typhoid Transmission. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America Andrews, J. R., Yu, A. T., Saha, S., Shakya, J., Aiemjoy, K., Horng, L., Qamar, F., Garrett, D., Baker, S., Saha, S., Luby, S. P. 2020; 71 (Supplement_2): S71–S78

    Abstract

    Enteric fever remains a major cause of morbidity in developing countries with poor sanitation conditions that enable fecal contamination of water distribution systems. Historical evidence has shown that contamination of water systems used for household consumption or agriculture are key transmission routes for Salmonella Typhi and Salmonella Paratyphi A. The World Health Organization now recommends that typhoid conjugate vaccines (TCV) be used in settings with high typhoid incidence; consequently, governments face a challenge regarding how to prioritize typhoid against other emerging diseases. A key issue is the lack of typhoid burden data in many low- and middle-income countries where TCV could be deployed. Here we present an argument for utilizing environmental sampling for the surveillance of enteric fever organisms to provide data on community-level typhoid risk. Such an approach could complement traditional blood culture-based surveillance or even replace it in settings where population-based clinical surveillance is not feasible. We review historical studies characterizing the transmission of enteric fever organisms through sewage and water, discuss recent advances in the molecular detection of typhoidal Salmonella in the environment, and outline challenges and knowledge gaps that need to be addressed to establish environmental sampling as a tool for generating actionable data that can inform public health responses to enteric fever.

    View details for DOI 10.1093/cid/ciaa513

    View details for PubMedID 32725227

  • The Surveillance for Enteric Fever in Asia Project (SEAP), Severe Typhoid Fever Surveillance in Africa (SETA), Surveillance of Enteric Fever in India (SEFI), and Strategic Typhoid Alliance Across Africa and Asia (STRATAA) Population-based Enteric Fever Studies: A Review of Methodological Similarities and Differences. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America Carey, M. E., MacWright, W. R., Im, J., Meiring, J. E., Gibani, M. M., Park, S. E., Longley, A., Jeon, H. J., Hemlock, C., Yu, A. T., Soura, A., Aiemjoy, K., Owusu-Dabo, E., Terferi, M., Islam, S., Lunguya, O., Jacobs, J., Gordon, M., Dolecek, C., Baker, S., Pitzer, V. E., Yousafzai, M. T., Tonks, S., Clemens, J. D., Date, K., Qadri, F., Heyderman, R. S., Saha, S. K., Basnyat, B., Okeke, I. N., Qamar, F. N., Voysey, M., Luby, S., Kang, G., Andrews, J., Pollard, A. J., John, J., Garrett, D., Marks, F. 2020; 71 (Supplement_2): S102–S110

    Abstract

    Building on previous multicountry surveillance studies of typhoid and others salmonelloses such as the Diseases of the Most Impoverished program and the Typhoid Surveillance in Africa Project, several ongoing blood culture surveillance studies are generating important data about incidence, severity, transmission, and clinical features of invasive Salmonella infections in sub-Saharan Africa and South Asia. These studies are also characterizing drug resistance patterns in their respective study sites. Each study answers a different set of research questions and employs slightly different methodologies, and the geographies under surveillance differ in size, population density, physician practices, access to healthcare facilities, and access to microbiologically safe water and improved sanitation. These differences in part reflect the heterogeneity of the epidemiology of invasive salmonellosis globally, and thus enable generation of data that are useful to policymakers in decision-making for the introduction of typhoid conjugate vaccines (TCVs). Moreover, each study is evaluating the large-scale deployment of TCVs, and may ultimately be used to assess post-introduction vaccine impact. The data generated by these studies will also be used to refine global disease burden estimates. It is important to ensure that lessons learned from these studies not only inform vaccination policy, but also are incorporated into sustainable, low-cost, integrated vaccine-preventable disease surveillance systems.

    View details for DOI 10.1093/cid/ciaa367

    View details for PubMedID 32725221

  • Linear growth in preschool children treated with mass azithromycin distributions for trachoma: A cluster-randomized trial. PLoS neglected tropical diseases Keenan, J. D., Gebresillasie, S., Stoller, N. E., Haile, B. A., Tadesse, Z., Cotter, S. Y., Ray, K. J., Aiemjoy, K., Porco, T. C., Callahan, E. K., Emerson, P. M., Lietman, T. M. 2019; 13 (6): e0007442

    Abstract

    BACKGROUND: Mass azithromycin distributions have been shown to reduce mortality among pre-school children in sub-Saharan Africa. It is unclear what mediates this mortality reduction, but one possibility is that antibiotics function as growth promoters for young children.METHODS AND FINDINGS: 24 rural Ethiopian communities that had received biannual mass azithromycin distributions over the previous four years were enrolled in a parallel-group, cluster-randomized trial. Communities were randomized in a 1:1 ratio to either continuation of biannual oral azithromycin (20mg/kg for children, 1 g for adults) or to no programmatic antibiotics over the 36 months of the study period. All community members 6 months and older were eligible for the intervention. The primary outcome was ocular chlamydia; height and weight were measured as secondary outcomes on children less than 60 months of age at months 12 and 36. Study participants were not masked; anthropometrists were not informed of the treatment allocation. Anthropometric measurements were collected for 282 children aged 0-36 months at the month 12 assessment and 455 children aged 0-59 months at the month 36 assessment, including 207 children who had measurements at both time points. After adjusting for age and sex, children were slightly but not significantly taller in the biannually treated communities (84.0 cm, 95%CI 83.2-84.8, in the azithromycin-treated communities vs. 83.7 cm, 95%CI 82.9-84.5, in the untreated communities; mean difference 0.31 cm, 95%CI -0.85 to 1.47, P = 0.60). No adverse events were reported.CONCLUSIONS: Periodic mass azithromycin distributions for trachoma did not demonstrate a strong impact on childhood growth.TRIAL REGISTRATION: The TANA II trial was registered on clinicaltrials.gov #NCT01202331.

    View details for DOI 10.1371/journal.pntd.0007442

    View details for PubMedID 31166952

  • Viral species richness and composition in young children with loose or watery stool in Ethiopia. BMC infectious diseases Aiemjoy, K., Altan, E., Aragie, S., Fry, D. M., Phan, T. G., Deng, X., Chanyalew, M., Tadesse, Z., Callahan, E. K., Delwart, E., Keenan, J. D. 2019; 19 (1): 53

    Abstract

    BACKGROUND: Stool consistency is an important diagnostic criterion in both research and clinical medicine and is often used to define diarrheal disease.METHODS: We examine the pediatric enteric virome across stool consistencies to evaluate differences in richness and community composition using fecal samples collected from children aged 0 to 5years participating in a clinical trial in the Amhara region of Ethiopia. The consistency of each sample was graded according to the modified Bristol Stool Form Scale for children (mBSFS-C) before a portion of stool was preserved for viral metagenomic analysis. Stool samples were grouped into 29 pools according to stool consistency type. Differential abundance was determined using negative-binomial modeling.RESULTS: Of 446 censused children who were eligible to participate, 317 presented for the study visit examination and 269 provided stool samples. The median age of children with stool samples was 36months. Species richness was highest in watery-consistency stool and decreased as stool consistency became firmer (Spearman's r=-0.45, p=0.013). The greatest differential abundance comparing loose or watery to formed stool was for norovirus GII (7.64, 95% CI 5.8, 9.5) followed by aichivirus A (5.93, 95% CI 4.0, 7.89) and adeno-associated virus 2 (5.81, 95%CI 3.9, 7.7).CONCLUSIONS: In conclusion, we documented a difference in pediatric enteric viromes according to mBSFS-C stool consistency category, both in species richness and composition.

    View details for PubMedID 30642268

  • WIDESPREAD ANTIBIOTIC USE AMONG SUSPECTED ENTERIC FEVER CASES IN NEPAL, BANGLADESH AND PAKISTAN Vaidya, K., Aiemjoy, K., Qamar, F. N., Saha, S. K., Barkume, C., Garrett, D., Luby, S. P., Andrews, J. R. AMER SOC TROP MED & HYGIENE. 2019: 590–91
  • SEROPREVALENCE OF ANTIBODIES AGAINST CHLAMYDIA TRACHOMATIS AND ENTEROPATHOGENS AND DISTANCE TO THE NEAREST WATER SOURCE AMONG YOUNG CHILDREN IN THE AMHARA REGION OF ETHIOPIA Aiemjoy, K., Aragie, S., Fry, D. M., Tadesse, Z., Callahan, E., Gwyn, S., Martin, D., Keenan, J. D., Arnold, B. F. AMER SOC TROP MED & HYGIENE. 2019: 609
  • COMPARATIVE EFFICACY OF DNA ISOLATION FROM RECTAL SWABS AND BULK STOOL FOR MOLECULAR DETECTION OF GIARDIA INTESTINALIS Maasch, J. R., Arzika, A. M., Cook, C., Lebas, E., Pilotte, N., Grant, J. R., Williams, S. A., Keenan, J. A., Aiemjoy, K. A. AMER SOC TROP MED & HYGIENE. 2019: 176
  • Enteric virome of Ethiopian children participating in a clean water intervention trial PLOS ONE Altan, E., Aiemjoy, K., Pha, T. G., Deng, X., Aragie, S., Tadesse, Z., Callahan, K. E., Keenan, J., Delwart, E. 2018; 13 (8): e0202054

    Abstract

    The enteric viruses shed by different populations can be influenced by multiple factors including access to clean drinking water. We describe here the eukaryotic viral genomes in the feces of Ethiopian children participating in a clean water intervention trial.Fecal samples from 269 children with a mean age of 2.7 years were collected from 14 villages in the Amhara region of Ethiopia, half of which received a new hand-dug water well. Feces from these villages were then analyzed in 29 sample pools using viral metagenomics. A total of 127 different viruses belonging to 3 RNA and 3 DNA viral families were detected. Picornaviridae family sequence reads were the most commonly found, originating from 14 enterovirus and 6 parechovirus genotypes plus multiple members of four other picornavirus genera (cosaviruses, saliviruses, kobuviruses, and hepatoviruses). Picornaviruses with nearly identical capsid VP1 were detected in different pools reflecting recent spread of these viral strains. Next in read frequencies and positive pools were sequences from the Caliciviridae family including noroviruses GI and GII and sapoviruses. DNA viruses from multiple genera of the Parvoviridae family were detected (bocaviruses 1-4, bufavirus 3, and dependoparvoviruses), together with four species of adenoviruses and common anelloviruses shedding. RNA in the order Picornavirales and CRESS-DNA viral genomes, possibly originating from intestinal parasites or dietary sources, were also characterized. No significant difference was observed between the number of mammalian viruses shed from children from villages with and without a new water well.We describe an approach to estimate the efficacy of potentially virus transmission-reducing interventions and the first complete (DNA and RNA viruses) description of the enteric viromes of East African children. A wide diversity of human enteric viruses was found in both intervention and control groups. Mammalian enteric virome diversity was not reduced in children from villages with a new water well. This population-based sampling also provides a baseline of the enteric viruses present in Northern Ethiopia against which to compare future viromes.

    View details for PubMedID 30114205

  • DEFINING DIARRHEA: A POPULATION-BASED VALIDATION STUDY OF CAREGIVER-REPORTED STOOL CONSISTENCY IN THE AMHARA REGION OF ETHIOPIA Aiemjoy, K., Aragie, S., Gebresillasie, S., Fry, D., Dagnew, A., Hailu, D., Chanyalew, M., Tadesse, Z., Stewart, A., Callahan, K., Freeman, M., Neuhaus, J., Arnold, B., Keenan, J. AMER SOC TROP MED & HYGIENE. 2018: 246
  • Is Using a Latrine "a Strange Thing To Do"? A Mixed -Methods Study of Sanitation Preference and Behaviors in Rural Ethiopia AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE Aiemjoy, K., Stoller, N. E., Gebresillasie, S., Shiferaw, A., Tadesse, Z., Sewent, T., Ayele, B., Chanyalew, M., Aragie, S., Callahan, K., Stewart, A., Emerson, P. M., Lietman, T. M., Keenan, J. D., Oldenburg, C. E. 2017; 96 (1): 65–73

    Abstract

    Latrines are the most basic form of improved sanitation and are a common public health intervention. Understanding motivations for building and using latrines can help develop effective, sustainable latrine promotion programs. We conducted a mixed-methods study of latrine use in the Amhara region of Ethiopia. We held 15 focus group discussions and surveyed 278 households in five communities. We used the Integrated Behavioral Model for Water, Sanitation, and Hygiene interventions to guide our qualitative analysis. Seventy-one percent of households had a latrine, but coverage varied greatly across communities. Higher household income was not associated with latrine use (odds ratio [OR] = 1.9; 95% confidence interval [CI] = 0.5, 7.7); similarly, cost and availability of materials were not discussed as barriers to latrine use in the focus groups. Male-headed households were more likely to use latrines than households with female heads (OR = 3.5; 95% CI = 1.6, 7.7), and households with children in school were more likely to use latrines than households without children in school (OR = 2.3; 95% CI = 1.6, 3.3). These quantitative findings were confirmed in focus groups, where participants discussed how children relay health messages from school. Participants discussed how women prefer not to use latrines, often finding them strange or even scary. These findings are useful for public health implementation; they imply that community-level drivers are important predictors of household latrine use and that cost is not a significant barrier. These findings confirm that school-aged children may be effective conduits of health messages and suggest that latrines can be better marketed and designed for women.

    View details for PubMedID 28077741

  • Epidemiology of Soil-Transmitted Helminth and Intestinal Protozoan Infections in Preschool-Aged Children in the Amhara Region of Ethiopia AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE Aiemjoy, K., Gebresillasie, S., Stoller, N. E., Shiferaw, A., Tadesse, Z., Chanyalew, M., Aragie, S., Callahan, K., Keenan, J. D. 2017; 96 (4): 866–72

    Abstract

    AbstractIntestinal parasites are important contributors to global morbidity and mortality and are the second most common cause of outpatient morbidity in Ethiopia. This cross-sectional survey describes the prevalence of soil-transmitted helminths and intestinal protozoa in preschool children 0-5 years of age in seven communities in the Amhara region of Ethiopia, and investigates associations between infection, household water and sanitation characteristics, and child growth. Stool samples were collected from children 0-5 years of age, 1 g of sample was preserved in sodium acetate-acetic acid-formalin, and examined for intestinal helminth eggs and protozoa cysts ether-concentration method. A total of 212 samples were collected from 255 randomly selected children. The prevalence of Ascaris lumbricoides, Trichuris trichiura, and hookworm were 10.8% (95% confidence interval [CI] 6.6-15.1), 1.4% (95% CI = 0-3.0), and 0% (95% CI = 0-1.7), respectively. The prevalence of the pathogenic intestinal protozoa Giardia lamblia and Entamoeba histolytica/dispar were 10.4% (95% CI = 6.2-14.6) and 3.3% (95% CI = 0.09-5.7), respectively. Children with A. lumbricoides infections had lower height-for-age z-scores compared with those without, but were not more likely to have stunting. Compared with those without G. lamblia, children with G. lamblia infections had lower weight-for-age and weight-for-height z-scores and were more than five times as likely to meet the z-score definition for wasting (prevalence ratio = 5.42, 95% CI = 2.97-9.89). This article adds to a growing body of research on child growth and intestinal parasitic infections and has implications for their treatment and prevention in preschool-aged children.

    View details for PubMedID 28167597

  • 'If an Eye Is Washed Properly, It Means It Would See Clearly': A Mixed Methods Study of Face Washing Knowledge, Attitudes, and Behaviors in Rural Ethiopia PLOS NEGLECTED TROPICAL DISEASES Aiemjoy, K., Stoller, N. E., Gebresillasie, S., Shiferaw, A., Tadesse, Z., Sewnet, T., Ayele, B., Chanyalew, M., Callahan, K., Stewart, A., Emerson, P. M., Lietman, T. M., Keenan, J. D., Oldenburg, C. E. 2016; 10 (10): e0005099

    Abstract

    Face cleanliness is a core component of the SAFE (Surgery, Antibiotics, Facial cleanliness, and Environmental improvements) strategy for trachoma control. Understanding knowledge, attitudes, and behaviors related to face washing may be helpful for designing effective interventions for improving facial cleanliness.In April 2014, a mixed methods study including focus groups and a quantitative cross-sectional study was conducted in the East Gojjam zone of the Amhara region of Ethiopia. Participants were asked about face washing practices, motivations for face washing, use of soap (which may reduce bacterial load), and fly control strategies.Overall, both knowledge and reported practice of face washing was high. Participants reported they knew that washing their own face and their children's faces daily was important for hygiene and infection control. Although participants reported high knowledge of the importance of soap for face washing, quantitative data revealed strong variations by community in the use of soap for face washing, ranging from 4.4% to 82.2% of households reporting using soap for face washing. Cost and forgetfulness were cited as barriers to the use of soap for face washing. Keeping flies from landing on children was a commonly cited motivator for regular face washing, as was trachoma prevention.Interventions aiming to improve facial cleanliness for trachoma prevention should focus on habit formation (to address forgetfulness) and address barriers to the use of soap, such as reducing cost. Interventions that focus solely on improving knowledge may not be effective for changing face-washing behaviors.

    View details for DOI 10.1371/journal.pntd.0005099

    View details for Web of Science ID 000386676200062

    View details for PubMedID 27788186

    View details for PubMedCentralID PMC5082955

  • Characteristics of Latrines in Central Tanzania and Their Relation to Fly Catches PLOS ONE Irish, S., Aiemjoy, K., Torondel, B., Abdelahi, F., Ensink, J. J. 2013; 8 (7): e67951

    Abstract

    The disposal of human excreta in latrines is an important step in reducing the transmission of diarrhoeal diseases. However, in latrines, flies can access the latrine contents and serve as a mechanical transmitter of diarrhoeal pathogens. Furthermore, the latrine contents can be used as a breeding site for flies, which may further contribute to disease transmission. Latrines do not all produce flies, and there are some which produce only a few, while others can produce thousands. In order to understand the role of the latrine in determining this productivity, a pilot study was conducted, in which fifty latrines were observed in and around Ifakara, Tanzania. The characteristics of the latrine superstructure, use of the latrine, and chemical characteristics of pit latrine contents were compared to the numbers of flies collected in an exit trap placed over the drop hole in the latrine. Absence of a roof was found to have a significant positive association (t=3.17, p=0.003) with the total number of flies collected, and temporary superstructures, particularly as opposed to brick superstructures (z=4.26, p<0.001), and increased total solids in pit latrines (z=2.57, p=0.01) were significantly associated with increased numbers of blowflies leaving the latrine. The number of larvae per gram was significantly associated with the village from which samples were taken, with the largest difference between two villages outside Ifakara (z=2.12, p=0.03). The effect of latrine superstructure (roof, walls) on fly production may indicate that improvements in latrine construction could result in decreases in fly populations in areas where they transmit diarrhoeal pathogens.

    View details for DOI 10.1371/journal.pone.0067951

    View details for Web of Science ID 000324146200011

    View details for PubMedID 23874475

    View details for PubMedCentralID PMC3715525