A 5-Year intervention study on elimination of urogenital schistosomiasis in Zanzibar: Parasitological results of annual cross-sectional surveys.
<h4>Background</h4>The Zanzibar Elimination of Schistosomiasis Transmission (ZEST) project aimed to eliminate urogenital schistosomiasis as a public health problem from Pemba and to interrupt Schistosoma haematobium transmission from Unguja in 5 years.<h4>Methodology</h4>A re...
| Main Authors: | , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2019-05-01
|
| Series: | PLoS Neglected Tropical Diseases |
| Online Access: | https://doi.org/10.1371/journal.pntd.0007268 |
| _version_ | 1827795105784791040 |
|---|---|
| author | Stefanie Knopp Shaali M Ame Bobbie Person Jan Hattendorf Muriel Rabone Saleh Juma Juma Muhsin Iddi Simba Khamis Elizabeth Hollenberg Khalfan A Mohammed Fatma Kabole Said M Ali David Rollinson |
| author_facet | Stefanie Knopp Shaali M Ame Bobbie Person Jan Hattendorf Muriel Rabone Saleh Juma Juma Muhsin Iddi Simba Khamis Elizabeth Hollenberg Khalfan A Mohammed Fatma Kabole Said M Ali David Rollinson |
| author_sort | Stefanie Knopp |
| collection | DOAJ |
| description | <h4>Background</h4>The Zanzibar Elimination of Schistosomiasis Transmission (ZEST) project aimed to eliminate urogenital schistosomiasis as a public health problem from Pemba and to interrupt Schistosoma haematobium transmission from Unguja in 5 years.<h4>Methodology</h4>A repeated cross-sectional cluster-randomized trial was implemented from 2011/12 till 2017. On each island, 45 shehias were randomly assigned to receive one of three interventions: biannual mass drug administration (MDA) with praziquantel alone, or in combination with snail control or behavior change measures. In cross-sectional surveys, a single urine sample was collected from ~9,000 students aged 9- to 12-years and from ~4,500 adults aged 20- to 55-years annually, and from ~9,000 1st year students at baseline and the final survey. Each sample was examined for S. haematobium eggs by a single urine filtration. Prevalence and infection intensity were determined. Odds of infection were compared between the intervention arms.<h4>Principal findings</h4>Prevalence was reduced from 6.1% (95% confidence interval (CI): 4.5%-7.6%) to 1.7% (95% CI: 1.2%-2.2%) in 9- to 12-year old students, from 3.9% (95% CI: 2.8%-5.0%) to 1.5% (95% CI: 1.0%-2.0%) in adults, and from 8.8% (95% CI: 6.5%-11.2%) to 2.6% (95% CI: 1.7%-3.5%) in 1st year students from 2011/12 to 2017. In 2017, heavy infection intensities occurred in 0.4% of 9- to 12-year old students, 0.1% of adults, and 0.8% of 1st year students. Considering 1st year students in 2017, 13/45 schools in Pemba and 4/45 schools in Unguja had heavy infection intensities >1%. There was no significant difference in prevalence between the intervention arms in any study group and year.<h4>Conclusions/significance</h4>Urogenital schistosomiasis was eliminated as public health problem from most sites in Pemba and Unguja. Prevalence was significantly reduced, but transmission was not interrupted. Continued interventions that are adaptive and tailored to the micro-epidemiology of S. haematobium in Zanzibar are needed to sustain and advance the gains made by ZEST. |
| first_indexed | 2024-03-11T18:43:25Z |
| format | Article |
| id | doaj.art-31cf59f8c7f042b9a7b8fc6f9027e56d |
| institution | Directory Open Access Journal |
| issn | 1935-2727 1935-2735 |
| language | English |
| last_indexed | 2024-03-11T18:43:25Z |
| publishDate | 2019-05-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Neglected Tropical Diseases |
| spelling | doaj.art-31cf59f8c7f042b9a7b8fc6f9027e56d2023-10-12T05:32:21ZengPublic Library of Science (PLoS)PLoS Neglected Tropical Diseases1935-27271935-27352019-05-01135e000726810.1371/journal.pntd.0007268A 5-Year intervention study on elimination of urogenital schistosomiasis in Zanzibar: Parasitological results of annual cross-sectional surveys.Stefanie KnoppShaali M AmeBobbie PersonJan HattendorfMuriel RaboneSaleh JumaJuma MuhsinIddi Simba KhamisElizabeth HollenbergKhalfan A MohammedFatma KaboleSaid M AliDavid Rollinson<h4>Background</h4>The Zanzibar Elimination of Schistosomiasis Transmission (ZEST) project aimed to eliminate urogenital schistosomiasis as a public health problem from Pemba and to interrupt Schistosoma haematobium transmission from Unguja in 5 years.<h4>Methodology</h4>A repeated cross-sectional cluster-randomized trial was implemented from 2011/12 till 2017. On each island, 45 shehias were randomly assigned to receive one of three interventions: biannual mass drug administration (MDA) with praziquantel alone, or in combination with snail control or behavior change measures. In cross-sectional surveys, a single urine sample was collected from ~9,000 students aged 9- to 12-years and from ~4,500 adults aged 20- to 55-years annually, and from ~9,000 1st year students at baseline and the final survey. Each sample was examined for S. haematobium eggs by a single urine filtration. Prevalence and infection intensity were determined. Odds of infection were compared between the intervention arms.<h4>Principal findings</h4>Prevalence was reduced from 6.1% (95% confidence interval (CI): 4.5%-7.6%) to 1.7% (95% CI: 1.2%-2.2%) in 9- to 12-year old students, from 3.9% (95% CI: 2.8%-5.0%) to 1.5% (95% CI: 1.0%-2.0%) in adults, and from 8.8% (95% CI: 6.5%-11.2%) to 2.6% (95% CI: 1.7%-3.5%) in 1st year students from 2011/12 to 2017. In 2017, heavy infection intensities occurred in 0.4% of 9- to 12-year old students, 0.1% of adults, and 0.8% of 1st year students. Considering 1st year students in 2017, 13/45 schools in Pemba and 4/45 schools in Unguja had heavy infection intensities >1%. There was no significant difference in prevalence between the intervention arms in any study group and year.<h4>Conclusions/significance</h4>Urogenital schistosomiasis was eliminated as public health problem from most sites in Pemba and Unguja. Prevalence was significantly reduced, but transmission was not interrupted. Continued interventions that are adaptive and tailored to the micro-epidemiology of S. haematobium in Zanzibar are needed to sustain and advance the gains made by ZEST.https://doi.org/10.1371/journal.pntd.0007268 |
| spellingShingle | Stefanie Knopp Shaali M Ame Bobbie Person Jan Hattendorf Muriel Rabone Saleh Juma Juma Muhsin Iddi Simba Khamis Elizabeth Hollenberg Khalfan A Mohammed Fatma Kabole Said M Ali David Rollinson A 5-Year intervention study on elimination of urogenital schistosomiasis in Zanzibar: Parasitological results of annual cross-sectional surveys. PLoS Neglected Tropical Diseases |
| title | A 5-Year intervention study on elimination of urogenital schistosomiasis in Zanzibar: Parasitological results of annual cross-sectional surveys. |
| title_full | A 5-Year intervention study on elimination of urogenital schistosomiasis in Zanzibar: Parasitological results of annual cross-sectional surveys. |
| title_fullStr | A 5-Year intervention study on elimination of urogenital schistosomiasis in Zanzibar: Parasitological results of annual cross-sectional surveys. |
| title_full_unstemmed | A 5-Year intervention study on elimination of urogenital schistosomiasis in Zanzibar: Parasitological results of annual cross-sectional surveys. |
| title_short | A 5-Year intervention study on elimination of urogenital schistosomiasis in Zanzibar: Parasitological results of annual cross-sectional surveys. |
| title_sort | 5 year intervention study on elimination of urogenital schistosomiasis in zanzibar parasitological results of annual cross sectional surveys |
| url | https://doi.org/10.1371/journal.pntd.0007268 |
| work_keys_str_mv | AT stefanieknopp a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT shaalimame a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT bobbieperson a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT janhattendorf a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT murielrabone a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT salehjuma a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT jumamuhsin a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT iddisimbakhamis a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT elizabethhollenberg a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT khalfanamohammed a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT fatmakabole a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT saidmali a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT davidrollinson a5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT stefanieknopp 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT shaalimame 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT bobbieperson 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT janhattendorf 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT murielrabone 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT salehjuma 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT jumamuhsin 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT iddisimbakhamis 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT elizabethhollenberg 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT khalfanamohammed 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT fatmakabole 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT saidmali 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys AT davidrollinson 5yearinterventionstudyoneliminationofurogenitalschistosomiasisinzanzibarparasitologicalresultsofannualcrosssectionalsurveys |