Regular deworming and seasonality are potential challenges but also offer opportunities for hookworm elimination

The global health community has targeted the elimination of neglected tropical diseases (NTDs) including soil-transmitted helminthiasis by 2030. The elimination strategy has not changed from that of control using regular mass drug administration (MDA) with albendazole, WASH and education. Already doubts have been expressed about this achievement, principally because drugs do not interrupt transmission. We report here the findings of a cohort study aimed to identify host modifiable and environmental factors associated with hookworm infection and reinfection in rural communities in Kintampo North Municipality, Ghana. Faecal samples of 564 consented participants were screened for intestinal parasites at baseline, 9 months and 24 months using the Kato-Katz method. At each time point, positive cases were treated with a single dose of albendazole (400 mg) and their samples were again screened 10-14 days post-treatment to record treatment failures. The hookworm prevalence at the three-time points was 16.7%, 9.22% and 5.3% respectively, whilst treatment failure rates were 17.25%, 29.03% and 40.9% respectively. The intensities of hookworm infection (in eggs per gram) at the time points were 138.3, 40.5 and 135, which showed a likely association with wet and dry seasons. We posit that the very low intensity of hookworm infections in humans during the dry season offers a window of opportunity for any intervention that could drastically reduce the community worm burden before the rainy season.


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Abstract 24 The global health community has targeted the elimination of neglected tropical diseases (NTDs) which showed a likely association with wet and dry seasons. We posit that the very low intensity 38 of hookworm infections in humans during the dry season offers a window of opportunity for any 39 intervention that could drastically reduce the community worm burden before the rainy season. CC-BY 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted March 14, 2023. ;

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Hookworm disease is an important intestinal parasite infection that is highly endemic and ranks 46 the highest in Ghana. [1,2,3]. Humans get infected with hookworm when the soil-living third-47 stage larvae (L3) enter trans-dermally or when they are ingested. Upon entering a human host, L3  Hookworms are among the group of STH and other NTDs that are earmarked for elimination by 64 the year 2030, which Ghana has also endorsed. There are already doubts that this may not be . CC-BY 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

(which was not certified by peer review)
The copyright holder for this preprint this version posted March 14, 2023. ; https://doi.org/10.1101/2023.03.09.23287064 doi: medRxiv preprint achieved for multiple reasons, the principal among these is that MDA does not interrupt 66 transmission, as reviewed by Haldemann et al. [9]. 67 We report here the findings of a cohort study that was aimed at investigating host-modifiable 68 factors associated with hookworm infection and reinfection, and albendazole treatment response 69 in nine rural communities in the Kintampo North Municipality in the Bono East Region of Ghana. 70 We found that albendazole treatment whilst reducing the prevalence also leads to increased non-   Study sites and population 83 The study was conducted in nine rural communities in the Kintampo North Municipality of the 84 Bono Region of Ghana (Fig 1).

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. CC-BY 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

Results
. CC-BY 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. Of the 564 participants who gave faecal samples 94 were infected at baseline and the intensities of 108 infection were 89 (93.68%) light; 4 (4.21%) moderate and 2 (2.11%) heavy 89 (93.68%). The 109 recorded hookworm prevalence at the three-time points was 16.7% (95/564), 9.22% (48/524) and 110 5.3% (26/495) respectively and the corresponding albendazole treatment failure rates were 17.25% 111 (14/78), 29.03% (9/31) and 40.9% (9/22) respectively (Fig 2). The intensities of infection were 138.3 e.p.g., 40.5 e.p.g. and 135 e.p.g. respectively at the time 117 points (Figure 3). Figure 3 shows a significant reduction in the intensity of infections during the  spring when 4th~stage larvae emerge collectively and quickly mature to adults [15]. 164 Irrespective of the mechanism at play in hookworm transmission, the opportunity that this offers 165 for hookworm elimination is to implement efforts to drastically reduce the parasite load in 166 communities before the onset of the rainy season and that includes mass deworming in endemic 167 communities.

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Acknowledgements 169 We appreciate the support of the NIINE laboratory and fieldwork teams, along with that provided 170 by the staff of the Kintampo Health and Research Centre. We are also grateful to the chiefs, 171 community leaders and participants in the Kintampo-North Municipality.

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. CC-BY 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted March 14, 2023. ; https://doi.org/10.1101/2023.03.09.23287064 doi: medRxiv preprint