Investigating the Community-Level Variation in Hookworm Prevalence in the Kpandai District, Ghana: a Mixed-Methods Study
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Yale University EliScholar – A Digital Platform for Scholarly Publishing at Yale Public Health Theses School of Public Health January 2020 Investigating The Community-Level Variation In Hookworm Prevalence In The Kpandai District, Ghana: A Mixed-Methods Study Harry Hyunteh Hyunteh Kim [email protected] Follow this and additional works at: https://elischolar.library.yale.edu/ysphtdl Recommended Citation Kim, Harry Hyunteh Hyunteh, "Investigating The Community-Level Variation In Hookworm Prevalence In The Kpandai District, Ghana: A Mixed-Methods Study" (2020). Public Health Theses. 1960. https://elischolar.library.yale.edu/ysphtdl/1960 This Open Access Thesis is brought to you for free and open access by the School of Public Health at EliScholar – A Digital Platform for Scholarly Publishing at Yale. It has been accepted for inclusion in Public Health Theses by an authorized administrator of EliScholar – A Digital Platform for Scholarly Publishing at Yale. For more information, please contact [email protected]. INVESTIGATING THE COMMUNITY-LEVEL VARIATION IN HOOKWORM PREVALENCE IN THE KPANDAI DISTRICT, GHANA: A MIXED-METHODS STUDY A Thesis Submitted to the Department of Epidemiology of Microbial Diseases Yale University School of Public Health in Partial Fulfillment of the Requirements for the Degree of Master of Public Health May 2020 by Harry Hyunteh Kim May 2020 Kim 1 Abstract Soil-transmitted helminths are a major cause of disability and morbidity in resource- poor settings: over 1.5 billion are estimated to be at risk of infection. Human behaviors and household socioeconomic conditions that facilitate contact with contaminated soil may increase exposure to parasites. The primary objective of the study was to investigate the community-level variation in hookworm prevalence in the Kpandai district of Ghana. We used a mixed-methods approach to investigate behavioral, societal and environmental risk factors to hookworm exposure. 264 individuals from three neighboring villages (Jagbigbingdo [JG], Takumdo [TK], Wiae Chabor [WC]) were recruited using a convenience sampling strategy. Household questionnaires regarding WASH were administered, and a representative from each household answered a semi-structured interview. Soil samples were taken to assess environmental hospitability for parasites. JG had a 24.4% hookworm prevalence, compared to 1.5% for TK, and 6.9% in WC, noting a continued community-level variation. Household size was a significant risk factor (OR = 2.09, 95% CI [1.17, 3.74]), while severely food insecure status was a protective factor (OR = 0.32, 95% CI [0.12, 0.85]). Qualitative interviews revealed that there is potential for regional WASH interventions and educational campaigns have penetrated at the community level. Environmental conditions did not vary significantly between the three villages, and nor did behavioral patterns. Infrastructure improvements may be needed to actualize behavioral changes from latrine construction, to achieve a sustainable reduction in parasite transmission. Concentrated foci of hookworm infected households may continue transmission patterns in JG, retarding efforts to reduce transmission at the community-level. Kim 2 Acknowledgements I have leaned on the support and mentorship of many individuals throughout this project. I am firstly thankful to my advisor, Dr. Debbie Humphries, who had initially piqued my interest in joining this project two years ago. I am grateful for her help and guidance through all steps of the research, through the messy proposal drafts, my blind first steps doing field work in Ghana, and reminding me to take a step back and take deep breaths when I was treading through the mud. I also thank Dr. Teferi Adem for reviewing my work and providing an anthropological perspective and valuable insight. My immense gratitude goes to the team in Ghana, including Prof. Michael Wilson (Prof!), Jeffrey Sumboh, Mr. B, Mr. O, Adelaide and Issac, Flora and Yvonne, and all the others at the lab. Their hospitality and patience have made my stay in Ghana an unforgettable one, and they deserve much praise for their expertise in parasitology and spotting the good fufu joints. Special thanks go to Jamees and Joshua, our translators from the village, without whom this work would not have been possible. N’borbii Nibuu. This work was supported in part by the Downs International Health Student Travel Fellowship, and the Yale Jan A. J. Stolwijk Fellowship. I thank the members of the fellowship committees for reviewing and supporting my work in global health. Lastly, I would like to thank my friends and my family – Ryan, Jess, Mahrukh, Uzma, Andrea, Gyoorie, mom & dad – who have stood as emotional pillars during these wonky times. Kim 3 Table of Contents Abstract ................................................................................................................................. 2 Acknowledgements ................................................................................................................ 3 Introduction ........................................................................................................................... 6 Background ...................................................................................................................................... 6 Figure 1. Life cycle of intestinal hookworm (4) .................................................................................... 7 Hookworm and the environment ..................................................................................................... 7 Figure 2. Influences on exposure to hookworm infection ................................................................... 9 Global response to treatment .......................................................................................................... 9 Characteristics and Recent Developments in Ghana’s Kpandai District ........................................... 10 Hookworm infections in Kpandai District, Ghana ............................................................................ 11 Rationale ........................................................................................................................................ 11 Figure 3. Potential routes of hookworm exposure and infection ...................................................... 12 Methods ................................................................................................................................ 13 Sample Area ................................................................................................................................... 13 Sampling and recruitment .............................................................................................................. 13 Qualitative Interview design .......................................................................................................... 13 Questionnaire deployment and data analysis ................................................................................. 14 Interview administration and analysis ............................................................................................ 14 Laboratory analysis of fecal samples .............................................................................................. 15 Spatial and environmental data collection and analysis .................................................................. 15 Environmental sample analysis ...................................................................................................... 15 Isolation of helminth oocysts from soil ........................................................................................... 16 Ethical approval and considerations ............................................................................................... 16 Statistical analysis .......................................................................................................................... 16 Results .................................................................................................................................. 17 Study Enrollment and Characteristics of sample population ........................................................... 18 Table 1. Individual characteristics of Sample Population .................................................................. 18 Hookworm baseline infection: summary characteristics ................................................................. 19 Table 2. Cases and Prevalence of Helminth Infections at Baseline ................................................... 19 Figure 5. Variation in hookworm prevalence by community. ........................................................... 19 Hookworm treatment summary characteristics .............................................................................. 21 Table 3. Hookworm Infection Characteristics by Community ........................................................... 21 Figure 6. Fecal hookworm EPG before and after treatment. ............................................................ 22 Table 4. Household characteristics by community ............................................................................ 23 Household characteristics by community ....................................................................................... 23 Table 5. Bivariate and Multivariate Associations with Baseline Hookworm Infection ...................... 25 Bivariate regression analysis of risk factors for hookworm infection .............................................