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Zimbabwe, located in Southern Africa, faces a significant public health challenge due to schistosomiasis. We investigated this issue with emphasis on risk prediction of schistosomiasis for the entire population. To this end, we reviewed available data on schistosomiasis in Zimbabwe from a literature search covering the 1980-2022 period considering the potential impact of 26 environmental and socioeconomic variables obtained from public sources. We studied the population requiring praziquantel with regard to whether or not mass drug administration (MDA) had been regularly applied. Three machine-learning algorithms were tested for their ability to predict the prevalence of schistosomiasis in Zimbabwe based on the mean absolute error (MAE), the root mean squared error (RMSE) and the coefficient of determination (R2). The findings revealed different roles of the 26 factors with respect to transmission and there were particular variations between Schistosoma haematobium and S. mansoni infections. We found that the top-five correlation factors, such as the past (rather than current) time, unsettled MDA implementation, constrained economy, high rainfall during the warmest season, and high annual precipitation were closely associated with higher S. haematobium prevalence, while lower elevation, high rainfall during the warmest season, steeper slope, past (rather than current) time, and higher minimum temperature in the coldest month were rather related to higher S. mansoni prevalence. The random forest (RF) algorithm was considered as the formal best model construction method, with MAE = 0.108; RMSE = 0.143; and R2 = 0.517 for S. haematobium, and with the corresponding figures for S. mansoni being 0.053; 0.082; and 0.458. Based on this optimal model, the current total schistosomiasis prevalence in Zimbabwe under MDA implementation was 19.8%, with that of S. haematobium at 13.8% and that of S. mansoni at 7.1%, requiring annual MDA based on a population of 3,003,928. Without MDA, the current total schistosomiasis prevalence would be 23.2%, that of S. haematobium 17.1% and that of S. mansoni prevalence at 7.4%, requiring annual MDA based on a population of 3,521,466. The study reveals that MDA alone is insufficient for schistosomiasis elimination, especially that due to S. mansoni. This study predicts a moderate prevalence of schistosomiasis in Zimbabwe, with its elimination requiring comprehensive control measures beyond the currently used strategies, including health education, snail control, population surveillance and environmental management.
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Malaria has created a resurgence crisis in Zimbabwe's elimination continuum, diverging from global commitment to malaria elimination by 2030. This retrospective cohort study aimed to determine the risk factors associated with severe malaria in the Beitbridge and Lupane districts. Multistage sampling was used to recruit 2414 individuals recorded in the District Health Information Software2 Tracker database. The study used IBM SPSS 29.0.2.0(20) for data analysis, and odds ratios (ORs) to estimate the relative risk (RR; 95% C.I; p < 0.05). The study revealed significant relative risks (p-value < 0.05) for individuals who had no Long-Lasting Insecticidal Nets (Beitbridge 47.4; Lupane 12.3), those who owned but used the LLINs (Beitbridge 24.9; Lupane 7.83), those who slept outdoors during the night (Beitbridge 84.4; Lupane 1.93), and adults (Beitbridge 0.18; Lupane 0.22) compared to the corresponding reference groups. Other factors showed varying RR: sex (Beitbridge 126.1), prompt treatment (Beitbridge 6.78), hosting visitor(s) (Lupane 6.19), and residence (Lupane 1.94) compared to the corresponding reference groups. Risk factor management needs to focus on increasing local awareness of malaria, universal LLINs coverage of indoor and outdoor sleeping spaces, community-based programs on proper and consistent LLIN usage, screening of visitors from malaria-endemic areas, comprehensive entomological activities, mixed malaria interventions in rural hotspots, and future research on local malaria transmission dynamics. While Zimbabwe has the potential to meet the global goal of malaria elimination, success depends on overcoming the risk factors to sustain the gains already made among malaria elimination districts.
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Malaria , Zimbabwe/epidemiología , Humanos , Estudios Retrospectivos , Masculino , Femenino , Adulto , Malaria/epidemiología , Malaria/prevención & control , Adolescente , Adulto Joven , Niño , Persona de Mediana Edad , Preescolar , Factores de Riesgo , Lactante , Mosquiteros Tratados con Insecticida/estadística & datos numéricos , Estudios de Cohortes , Erradicación de la Enfermedad/estadística & datos numéricos , Control de Mosquitos/estadística & datos numéricos , AncianoRESUMEN
BACKGROUND: Practicing hand hygiene is recommended as one of the key preventive measures for reducing the transmission of COVID-19 and other infectious agents. However, it is often not practiced frequently enough or correctly by the public. We aimed to identify barriers to and facilitators of hand hygiene in the Zimbabwean population during the COVID-19 pandemic. METHODS: A qualitative study was conducted with a purposive sample of health workers, village health workers, church leaders, traditional healers, teachers, youth leaders and the general population selected from ten districts across the country from September to October 2022. Semistructured interviews were conducted with 3 key informant interviews per site. In addition, one homogenous focus group discussion was also conducted per site using a focus group discussion guide. The data were recorded on audiotapes, transcribed verbatim, and translated into English. All the analyses were performed manually using thematic analysis. RESULTS: Two themes were identified as facilitators of hand hygiene. These include individual factors (knowledge of hand hygiene practices and how they are performed) and access-related factors (access to hand washing infrastructure, soap, and sanitizers). Among the barriers to hand hygiene, four themes were identified: individual factors (knowledge gaps in proper hand washing, lack of conviction about hand hygiene, and habitual behaviour), access-related factors (lack of access to hand washing infrastructure, soap, and sanitizers), safety concerns (concern about the side effects of sanitizers), and sociocultural and religious factors (social customs, cultural beliefs, values, and religious practices). CONCLUSION: During public health emergencies, there is a need for people to access uninterrupted, on-premises water supplies to promote compliance with hand hygiene. The provision of clean water and hand washing facilities is critical for vulnerable communities to afford them the opportunity to improve quality of life and facilitate resilience in the event of future pandemics. Community engagement is important for identifying vulnerability factors to provide appropriate mitigatory measures.
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COVID-19 , Higiene de las Manos , Adolescente , Humanos , COVID-19/prevención & control , Pandemias/prevención & control , Jabones , Calidad de Vida , Zimbabwe/epidemiología , Desinfección de las ManosRESUMEN
BACKGROUND: Vaccines are effective biological interventions that reduce health burdens. However, during the COVID-19 pandemic, there were concerns about varying levels of COVID-19 vaccination coverage in the Zimbabwean population. This study aimed to understand facilitators and barriers to COVID-19 vaccine uptake in the Zimbabwean population. METHODS: In September-October 2023, key informant interviews (KIIs) and focus group discussions (FGDs) were conducted with a sample comprising health workers, village health workers, church leaders, traditional healers, teachers, youth leaders and the general population selected across the country. At each site, the participant sample was homogeneous. Data were collected using audiotapes, transcribed verbatim, and translated into English. Data were analysed manually using thematic analysis. RESULTS: Ten FGDs and 30 KIIs were conducted across the country. Among the facilitators of COVID-19 vaccine uptake were the perceived benefits of COVID-19 vaccination, such as protection from infection, severe disease and death. People also complied with COVID-19 vaccination because of the government's call for mandatory vaccination, travel restrictions, restrictions when entering some premises for services, visiting, working, learning and functions. Barriers to COVID-19 vaccine uptake included low-risk perception, negative attitudes emanating from concerns about the origins of the vaccines, COVID-19 cases or death of vaccinated people, negative peer influence, religious doctrines, cultural beliefs and misconceptions circulating through social media. Other barriers included knowledge gaps on COVID-19 vaccines, safety, effectiveness, side effects, access-related challenges to COVID-19 services and concerns over the changing policy on COVID-19 vaccination. CONCLUSIONS: The study has shown the importance of community engagement and data-driven public health communication strategies to facilitate behaviour change for increased uptake of a vaccine. In future epidemics, public health campaigns should focus on the timely provision of information explaining the benefits of an intervention, addressing safety concerns more effectively. To build trust and hence improve vaccine uptake by the public, there is a need for continuous engagement with people and to provide platforms for dialogue to address issues contributing to low vaccine uptake.
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Vacunas contra la COVID-19 , COVID-19 , Grupos Focales , Investigación Cualitativa , Humanos , Zimbabwe , COVID-19/prevención & control , COVID-19/epidemiología , Vacunas contra la COVID-19/administración & dosificación , Femenino , Masculino , Adulto , Persona de Mediana Edad , Conocimientos, Actitudes y Práctica en Salud , Vacilación a la Vacunación/psicología , Vacilación a la Vacunación/estadística & datos numéricos , Vacunación/estadística & datos numéricos , Vacunación/psicología , Adulto Joven , Adolescente , SARS-CoV-2 , Cobertura de Vacunación/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Aceptación de la Atención de Salud/psicologíaRESUMEN
BACKGROUND: While many studies from sub-Saharan countries, including Zimbabwe, allude to the important role of religion and tradition for young people living with HIV (YPLHIV), most of these studies tend to be descriptive and lack advanced statistical analysis. This study aims to close this gap. METHODS: Data for this study was collected between July and October 2021 from 804 YPLHIV (aged 14-24) in Zimbabwe. The questionnaire included questions regarding participants' conceptions of HIV, their health seeking and risk-taking behaviour, current HIV viral load results, the prevalence of opportunistic infections, their mental health status, and demographic characteristics. The analysis was done using multilevel mixed-effects logistic regression. RESULTS: We found that Traditional religious affiliation was linked to overall lower viral load (OR: 0.34; CI: 0.12-0.96; P: 0.042), Apostolic to more (OR: 1.52; CI: 1-2.3; P: 0.049) and Pentecostal to less (OR: 0.53; CI: 0.32-0.95; P: 0.033) treatment failure. Additionally, conceptions about HIV without spiritual or religious connotation, such as 'seeing HIV as result of a weak body' was associated with lower risk of treatment failure (OR: 0.6; CI: 0.4-1.0; P: 0.063), higher chances for undetectable viral load (OR: 1.4; CI: 1-2; P: 0.061), and overall lower viral load (OR: 0.7; CI: 0.5-1; P: 0.067). Moralizing concepts of HIV, like 'seeing HIV as a result of sin in the family', was linked to higher risk of opportunistic infections (OR:1.8; CI:1.1-3; P: 0.018), and higher risk of treatment failure (OR: 1.7; CI: 0.7-1.1; P: 0.066). Religious objections toward certain forms of therapy, like toward cervical cancer screening, was linked to higher risk of mental problems (OR: 2.2; CI: 1.35-3.68; P: 0.002) and higher risk of opportunistic infections (OR:1.6; CI:1.1-2.1; P: 0.008). Religious affiliations significantly influenced conceptions of HIV, health seeking behaviour, and risk taking. CONCLUSION: To our knowledge, this study is the first to provide evidence about the statistically significant associations between religious and traditional beliefs and practices and current health outcomes and health risk factors of YPLHIV in Zimbabwe. It is also the first to identify empirically the role of religious affiliations as predictors of current viral load results. This new knowledge can inform contextualized approaches to support YPLHIV in Zimbabwe.
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Infecciones por VIH , Infecciones Oportunistas , Neoplasias del Cuello Uterino , Femenino , Humanos , Adolescente , Detección Precoz del Cáncer , Factores de Riesgo , Infecciones por VIH/prevención & control , Asunción de Riesgos , Evaluación de Resultado en la Atención de Salud , Zimbabwe/epidemiologíaRESUMEN
INTRODUCTION: The role of religion and spirituality as social determinants of health has been widely discussed. Studies among people living with HIV describe positive and negative influences of religion and spirituality on health outcomes. With a HIV prevalence of 14.8% for females and 8.6% for males, and 22 000 AIDS-related deaths in 2020, HIV infection remains a life-threatening condition in Zimbabwe, especially in young people. The aim of this research was to measure the influence of religion and spirituality on the health outcomes of young people living with HIV in Zimbabwe. METHODS: A quantitative questionnaire with three different validated measures of religion and spirituality (Belief into Action Scale, Brief Religious Coping Index, Religious and Spiritual Struggles Scale), demographic, cultural, behavioural and health questions was administered to 804 young Zvandiri programme clients in rural, urban and peri-urban Zimbabwe between July and October 2021. Regression analysis established significant relations between the result of the three different measures and mental health and viral load results. RESULTS: Religious coping significantly reduced the probability of common mental disorder, while high religious activity increased the risk. The Religious and Spiritual Struggles Scale proved to be a reliable indicator of higher viral loads, risk for treatment failure and the probability of common mental disorder. CONCLUSIONS: All three measures of religion and spirituality related to health outcomes. More research is needed to generalise and further explore these findings. Because the Religious and Spiritual Struggles Scale was a strong indicator for both, higher viral loads and common mental disorder, we suggest that it should be used and validated in other sub-Saharan contexts. It could serve as a new diagnostic tool for the early detection and prevention of treatment failure as well as of common mental disorder.
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Infecciones por VIH , Trastornos Mentales , Femenino , Masculino , Humanos , Adolescente , Salud Mental , Infecciones por VIH/epidemiología , Carga Viral , Zimbabwe/epidemiologíaRESUMEN
Introduction: Religious/spiritual convictions and practices can influence health- and treatment-seeking behavior, but only few measures of religiousness or spirituality have been validated and used outside of the US. The Religious and Spiritual Struggles scale (RSS) measures internal and external conflict with religion and spirituality and has been validated mainly in different high-income contexts. The aim of this study was the validation of the RSS in the Zimbabwean context and among young people living with human immunodeficiency virus (YPLHIV) aged 14-24. Methods: Data collection with an Open Data Kit (ODK) questionnaire with 804 respondents took place in 2021. The validation was performed by confirmatory factor analysis (CFA), using statistical equation modeling (SEM), and Mokken scale analysis (MSA). After the low confirmability of the original scale sub-dimensions exploratory factor analysis (EFA) was applied. Results: The EFA resulted in four new sub-domains that were different from the original six domains in the RSS but culturally more relevant. The new sub-domains are significantly related to health. Discussion: The findings support the validity and relevance of the RSS and the new sub-domains in this context. As our study was limited to YPLHIV, further validation of the RSS among different population groups and contexts in the sub-Saharan region is encouraged.
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Schistosomiasis is a helminthiasis infecting approximately 250 million people worldwide. In 2001, the World Health Assembly (WHA) 54.19 resolution defined a new global strategy for control of schistosomiasis through preventive chemotherapy programmes. This resolution culminated in the 2006 WHO guidelines that recommended empirical treatment by mass drug administration with praziquantel, predominately to school-aged children in endemic settings at regular intervals. Since then, school-based and community-based preventive chemotherapy programmes have been scaled-up, reducing schistosomiasis-associated morbidity. Over the past 15 years, new scientific evidence-combined with a more ambitious goal of eliminating schistosomiasis and an increase in the global donated supply of praziquantel-has highlighted the need to update public health guidance worldwide. In February, 2022, WHO published new guidelines with six recommendations to update the global public health strategy against schistosomiasis, including expansion of preventive chemotherapy eligibility from the predominant group of school-aged children to all age groups (2 years and older), lowering the prevalence threshold for annual preventive chemotherapy, and increasing the frequency of treatment. This Review, written by the 2018-2022 Schistosomiasis Guidelines Development Group and its international partners, presents a summary of the new WHO guideline recommendations for schistosomiasis along with their historical context, supporting evidence, implications for public health implementation, and future research needs.
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Antihelmínticos , Helmintiasis , Esquistosomiasis , Niño , Humanos , Preescolar , Praziquantel/uso terapéutico , Esquistosomiasis/tratamiento farmacológico , Esquistosomiasis/epidemiología , Esquistosomiasis/prevención & control , Helmintiasis/tratamiento farmacológico , Administración Masiva de Medicamentos , Prevalencia , Organización Mundial de la Salud , Antihelmínticos/uso terapéuticoRESUMEN
Although pay-for-performance (P4P) schemes have been implemented across low- and middle-income countries (LMICs), little is known about their distributional consequences. A key concern is that financial bonuses are primarily captured by providers who are already better able to perform (for example, those in wealthier areas), P4P could exacerbate existing inequalities within the health system. We examine inequalities in the distribution of pay-outs in Zimbabwe's national P4P scheme (2014-2016) using quantitative data on bonus payments and facility characteristics and findings from a thematic policy review and 28 semi-structured interviews with stakeholders at all system levels. We found that in Zimbabwe, facilities with better baseline access to guidelines, more staff, higher consultation volumes and wealthier and less remote target populations earned significantly higher P4P bonuses throughout the programme. For instance, facilities that were 1 SD above the mean in terms of access to guidelines, earned 90 USD more per quarter than those that were 1 SD below the mean. Differences in bonus pay-outs for facilities that were 1 SD above and below the mean in terms of the number of staff and consultation volumes are even more pronounced at 348 USD and 445 USD per quarter. Similarly, facilities with villages in the poorest wealth quintile in their vicinity earned less than all others-and 752 USD less per quarter than those serving villages in the richest quintile. Qualitative data confirm these findings. Respondents identified facility baseline structural quality, leadership, catchment population size and remoteness as affecting performance in the scheme. Unequal distribution of P4P pay-outs was identified as having negative consequences on staff retention, absenteeism and motivation. Based on our findings and previous work, we provide some guidance to policymakers on how to design more equitable P4P schemes.
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Instituciones de Salud , Reembolso de Incentivo , Humanos , Motivación , Salarios y Beneficios , ZimbabweRESUMEN
BACKGROUND: Over the past 20 years, schistosomiasis control has been scaled up. Preventive chemotherapy with praziquantel is the main intervention. We aimed to assess the effect of preventive chemotherapy on schistosomiasis prevalence in sub-Saharan Africa, comparing 2000-10 with 2011-14 and 2015-19. METHODS: In this spatiotemporal modelling study, we analysed survey data from school-aged children (aged 5-14 years) in 44 countries across sub-Saharan Africa. The data were extracted from the Global Neglected Tropical Diseases database and augmented by 2018 and 2019 survey data obtained from disease control programmes. Bayesian geostatistical models were fitted to Schistosoma haematobium and Schistosoma mansoni survey data. The models included data on climatic predictors obtained from satellites and other open-source environmental databases and socioeconomic predictors obtained from various household surveys. Temporal changes in Schistosoma species prevalence were estimated by a categorical variable with values corresponding to the three time periods (2000-10, 2011-14, and 2015-19) during which preventive chemotherapy interventions were scaled up. FINDINGS: We identified 781 references with relevant geolocated schistosomiasis survey data for 2000-19. There were 19 166 unique survey locations for S haematobium and 23 861 for S mansoni, of which 77% (14 757 locations for S haematobium and 18 372 locations for S mansoni) corresponded to 2011-19. Schistosomiasis prevalence among school-aged children in sub-Saharan Africa decreased from 23·0% (95% Bayesian credible interval 22·1-24·1) in 2000-10 to 9·6% (9·1-10·2) in 2015-19, an overall reduction of 58·3%. The reduction of S haematobium was 67·9% (64·6-71·1) and that of S mansoni 53·6% (45·2-58·3) when comparing 2000-10 with 2015-19. INTERPRETATION: Our model-based estimates suggest that schistosomiasis prevalence in sub-Saharan Africa has decreased considerably, most likely explained by the scale-up of preventive chemotherapy. There is a need to consolidate gains in the control of schistosomiasis by means of preventive chemotherapy, coupled with other interventions to interrupt disease transmission. FUNDING: European Research Council and WHO.
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Antihelmínticos/uso terapéutico , Praziquantel/uso terapéutico , Schistosoma haematobium/efectos de los fármacos , Schistosoma mansoni/efectos de los fármacos , Esquistosomiasis/tratamiento farmacológico , Análisis Espacio-Temporal , Adolescente , África del Sur del Sahara/epidemiología , Animales , Quimioprevención , Niño , Preescolar , Estudios Transversales , Bases de Datos Factuales , Humanos , Praziquantel/administración & dosificación , Prevalencia , Esquistosomiasis/clasificación , Esquistosomiasis/epidemiología , Instituciones AcadémicasRESUMEN
Maps of the geographical variation in prevalence play an important role in large-scale programs for the control of neglected tropical diseases. Precontrol mapping is needed to establish the appropriate control intervention in each area of the country in question. Mapping is also needed postintervention to measure the success of control efforts. In the absence of comprehensive disease registries, mapping efforts can be informed by 2 kinds of data: empirical estimates of local prevalence obtained by testing individuals from a sample of communities within the geographical region of interest, and digital images of environmental factors that are predictive of local prevalence. In this article, we focus on the design and analysis of impact surveys, that is, prevalence surveys that are conducted postintervention with the aim of informing decisions on what further intervention, if any, is needed to achieve elimination of the disease as a public health problem. We show that geospatial statistical methods enable prevalence surveys to be designed and analyzed as efficiently as possible so as to make best use of hard-won field data. We use 3 case studies based on data from soil-transmitted helminth impact surveys in Kenya, Sierra Leone, and Zimbabwe to compare the predictive performance of model-based geostatistics with methods described in current World Health Organization (WHO) guidelines. In all 3 cases, we find that model-based geostatistics substantially outperforms the current WHO guidelines, delivering improved precision for reduced field-sampling effort. We argue from experience that similar improvements will hold for prevalence mapping of other neglected tropical diseases.
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Helmintiasis , Helmintos , Animales , Humanos , Kenia , Enfermedades Desatendidas , Prevalencia , Sierra Leona , Suelo , ZimbabweRESUMEN
BACKGROUND: Microscopy and rapid diagnostic tests (RDTs) are the main techniques used to diagnose malaria. While microscopy is considered the gold standard, RDTs have established popularity as they allow for rapid diagnosis with minimal technical skills. This study aimed to compare the diagnostic performance of two Plasmodium falciparum histidine-rich protein 2 (PfHRP2)-based RDTs (Paracheck Pf® Test (Paracheck) and Malaria Pf™ ICT (ICT)) to polymerase chain reaction (PCR) in a community survey. METHODS: A cross-sectional study was conducted between October 2012 and December 2014 in Mutasa District, Manicaland Province, eastern Zimbabwe. Households were randomly selected using satellite imagery, and 224 households were visited. Residents present in the household on the date of the visit were recruited for the study. Participants of all age groups from the selected households were screened with Paracheck and ICT RDTs in parallel. Dried blood spots (DBS) and thin and thick smears were collected. Parasite DNA extracted from the DBS was subjected to nested PCR targeting the Plasmodium cytochrome b mitochondrial gene. Data analysis was performed using the Cohen's Kappa test to determine the interrater agreement and the sensitivity and specificity of the diagnostic test were reported. RESULTS: Results from a total of 702 participants were analysed. Most were females, 397 (57%), and the median age of participants was 21 years with an interquartile range of 9-39 years. Of those who were screened, 8 (1.1%), 35 (5.0%), and 21 (2.9%) were malaria parasite positive by microscopy, RDT and PCR, respectively. Paracheck and ICT RDTs had a 100% agreement. Comparing RDT and PCR results, 34 participants (4.8%) had discordant results. Most of the discordant cases were RDT positive but PCR negative (n = 24). Half of those RDT positive, but PCR negative individuals reported anti-malarials to use in the past month, which is significantly higher than reported anti-malarial drug use in the population (p < 0.001). The participant was febrile on the day of the visit, but relying on PfHRP2-based RDT would miss this case. Among the diagnostic methods evaluated, with reference to PCR, the sensitivity was higher with the RDT (52.4%) while specificity was higher with the microscopy (99.9%). The positive predictive value (PPV) was higher with the microscopy (87.5%), while the negative predictive values were similar for both microscopy and RDTs (98%). Overall, a strong correlated agreement with PCR was observed for the microscopy (97.9%) and the RDTs (95.2%). CONCLUSIONS: Paracheck and ICT RDTs showed 100% agreement and can be used interchangeably. As malaria transmission declines and Zimbabwe aims to reach malaria elimination, management of infected individuals with low parasitaemia as well as non-P. falciparum infection can be critical.
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Malaria Falciparum/epidemiología , Parasitemia/epidemiología , Plasmodium falciparum/aislamiento & purificación , Adolescente , Adulto , Niño , Preescolar , Estudios Transversales , Pruebas Diagnósticas de Rutina/métodos , Femenino , Humanos , Malaria Falciparum/parasitología , Masculino , Persona de Mediana Edad , Parasitemia/parasitología , Prevalencia , Sensibilidad y Especificidad , Adulto Joven , Zimbabwe/epidemiologíaRESUMEN
Removal of chloroquine from national malaria formularies can lead to the reversion of resistant Plasmodium falciparum to wild-type. We report a steep decline in chloroquine-resistant P falciparum within 10 years of national discontinuation of chloroquine monotherapy in Zimbabwe. Drug resistance surveillance is a vital component of malaria control programs, and the experience with chloroquine in Zimbabwe and elsewhere in sub-Saharan Africa is illustrative of the potentially rapid and dramatic impact of drug policy on antimalarial resistance.
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Cloroquina/farmacología , Resistencia a Medicamentos , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Carga de Parásitos , Plasmodium falciparum/efectos de los fármacos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Cloroquina/uso terapéutico , Femenino , Humanos , Lactante , Malaria Falciparum/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Vigilancia en Salud Pública , Adulto Joven , Zimbabwe/epidemiologíaRESUMEN
This paper reports the prevalence and intensity of soil-transmitted helminth (STH) infections measured in Zimbabwe before and after a control intervention based on annual deworming of school-age children (SAC) conducted from 2012 to 2018. In 2010, epidemiological data were collected from 13 195 SAC in 255 randomly selected schools in all districts nationwide using, as diagnostic methods, the Kato-Katz and the formal ether stool concentration technique. At follow up, conducted in 2017, only Kato-Katz was performed; specimens were collected from 13 352 children in 336 schools. The data were evaluated using a geospatial approach. The national prevalence of STH infection in SAC was estimated at 5.8% at baseline, with 0.8% of infections of moderate and heavy intensity. Preventive chemotherapy (PC) targeted all 2.5 million children of school age enrolled in Zimbabwe, with coverage ranging from 49% to 85%. At follow up, national prevalence of STH in SAC was estimated at 0.8%; infections of moderate and heavy intensity almost disappeared (0.1% prevalence). As a result, Zimbabwe can suspend deworming activities in 54 districts and reduce the frequency of PC in the remaining six districts. The total amount of albendazole tablets needed will be approximately 100 000 a year.
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Antihelmínticos/administración & dosificación , Ascariasis/epidemiología , Infecciones por Uncinaria/epidemiología , Administración Masiva de Medicamentos , Tricuriasis/epidemiología , Adolescente , Albendazol/administración & dosificación , Ancylostomatoidea/aislamiento & purificación , Animales , Ascariasis/prevención & control , Ascaris lumbricoides/aislamiento & purificación , Quimioprevención , Niño , Heces/parasitología , Femenino , Geografía , Helmintiasis/epidemiología , Helmintiasis/prevención & control , Infecciones por Uncinaria/prevención & control , Humanos , Masculino , Prevalencia , Análisis de Regresión , Instituciones Académicas , Suelo/parasitología , Análisis Espacial , Tricuriasis/prevención & control , Trichuris/aislamiento & purificación , Zimbabwe/epidemiologíaRESUMEN
BACKGROUND: Treatment needs for Schistosoma haematobium are commonly evaluated using urine filtration with detection of parasite eggs under a microscope. A common symptom of S. haematobium is hematuria, the passing of blood in urine. Hence, the use of hematuria-based diagnostic techniques as a proxy for the assessment of treatment needs has been considered. This study evaluates data from a national survey in Zimbabwe, where three hematuria-based diagnostic techniques, that is microhematuria, macrohematuria, and an anamnestic questionnaire pertaining to self-reported blood in urine, have been included in addition to urine filtration in 280 schools across 70 districts. METHODOLOGY: We developed an egg count model, which evaluates the infection intensity-dependent sensitivity and the specificity of each diagnostic technique without relying on a 'gold' standard. Subsequently, we determined prevalence thresholds for each diagnostic technique, equivalent to a 10% urine filtration-based prevalence and compared classification of districts according to treatment strategy based on the different diagnostic methods. PRINCIPAL FINDINGS: A 10% urine filtration prevalence threshold corresponded to a 17.9% and 13.3% prevalence based on questionnaire and microhematuria, respectively. Both the questionnaire and the microhematuria showed a sensitivity and specificity of more than 85% for estimating treatment needs at the above thresholds. For diagnosis at individual level, the questionnaire showed the highest sensitivity (70.0%) followed by urine filtration (53.8%) and microhematuria (52.2%). CONCLUSIONS/SIGNIFICANCE: The high sensitivity and specificity of a simple questionnaire to estimate treatment needs of S. haematobium suggests that it can be used as a rapid, low-cost method to estimate district prevalence. Our modeling approach can be expanded to include setting-dependent specificity of the technique and should be assessed in relation to other diagnostic methods due to potential cross-reaction with other diseases.
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Hematuria , Recuento de Huevos de Parásitos/métodos , Esquistosomiasis Urinaria/diagnóstico , Esquistosomiasis Urinaria/orina , Adolescente , Teorema de Bayes , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Sensibilidad y Especificidad , Encuestas y Cuestionarios , Zimbabwe/epidemiologíaRESUMEN
The fresh water snail Biomphalaria pfeifferi is the intermediate host for Schistosoma mansoni, which causes human intestinal schistosomiasis in Zimbabwe. Despite the medical importance of this intermediate host, there are no current data on its molecular characterization in Zimbabwe. In 2016, human water contact sites were identified in four communities in Madziwa area, Shamva district, Zimbabwe. The survey sites were recorded and mapped using a global positioning system. A 655 bp region of the mitochondrial cytochrome oxidase subunit I gene was amplified in 70 B. pfeifferi snails. The sequence data were analysed to determine the relationships between the individual snails, their inter, intra population diversity and structure. Overall, four unique cox1 haplotypes, with a haplotype diversity of 0.608, were identified in the snails. One haplotype spanned across most of the sites. There was no clear geographical clustering of haplotypes. The mean diversity among the haplotypes was very low (0.009), while the net divergence among the collection sites ranged from 0.000 to 0.026. The diversity within and between the sites was 0.017 and 0.012 respectively. This data advances our knowledge of the understanding of the population structure of B. pfeifferi in Madziwa area, Zimbabwe, with the high occurrence of one haplotype indicating the possibility of a recent bottleneck followed by population expansion. The population genetic structure of B. pfeifferi snails described here has provided an opportunity to investigate the contribution of snail genetics to variation in disease burden; and development of control strategies that exploit genetic differences in susceptibility to parasites.
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Gastrópodos/genética , Polimorfismo Genético , Esquistosomiasis mansoni/transmisión , Animales , Vectores de Enfermedades , Complejo IV de Transporte de Electrones/genética , Gastrópodos/parasitología , Genoma Mitocondrial , Haplotipos , Humanos , Schistosoma mansoni/patogenicidad , ZimbabweRESUMEN
BACKGROUND: Bulinus species are freshwater snails that transmit the parasitic trematode Schistosoma haematobium. Despite their importance, the diversity of these intermediate host snails and their evolutionary history is still unclear in Zimbabwe. Bulinus globosus and B. truncatus collected from a urogenital schistosomiasis endemic region in the Madziwa area of Zimbabwe were characterized using molecular methods. METHODS: Malacological survey sites were mapped and snails were collected from water contact sites in four communities in the Madziwa area, Shamva district for a period of one year, at three-month intervals. Schistosoma haematobium infections in snails were determined by cercarial shedding and the partial mitochondrial cytochrome c oxidase subunit 1 gene (cox1) was used to investigate the phylogeny and genetic variability of the Bulinus spp. collected. RESULTS: Among the 1570 Bulinus spp. snails collected, 30 (1.9%) B. globosus were shedding morphologically identified schistosomes. None of the B. truncatus snails were shedding. The mitochondrial cox1 data from 166 and 16 samples for B. globosus and B. truncatus, respectively, showed genetically diverse populations within the two species. Twelve cox1 haplotypes were found from the 166 B. globosus samples and three from the 16 B. truncatus samples with phylogenetic analysis showing that the haplotypes fall into well-supported clusters within their species groups. Both B. truncatus and B. globosus clustered into two distinct lineages. Overall, significant negative values for both Tajima's D statistic and the Fu's Fs statistic were observed for B. globosus and B. truncatus. CONCLUSIONS: The study provided new insights into the levels of genetic diversity within B. globosus and additional information on B. truncatus collected from a small geographical area in Zimbabwe. Low prevalence levels of infection observed in the snails may reflect the low transmission level of urogenital schistosomiasis in the area. Our results contribute towards the understanding of the distribution and population genetic structure of Bulinus spp. supporting the mapping of the transmission or risk of transmission of urogenital schistosomiasis, particularly in Zimbabwe.
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Bulinus/parasitología , Schistosoma haematobium/genética , Esquistosomiasis Urinaria/transmisión , Animales , Cercarias/aislamiento & purificación , Complejo IV de Transporte de Electrones/genética , Agua Dulce/parasitología , Variación Genética , Especificidad del Huésped , Filogenia , Prevalencia , Schistosoma haematobium/parasitología , ZimbabweRESUMEN
BACKGROUND: Trichiasis is present when one or more eyelashes touches the eye. Uncorrected, it can cause blindness. Accurate estimates of numbers affected, and their geographical distribution, help guide resource allocation. METHODS: We obtained district-level trichiasis prevalence estimates in adults for 44 endemic and previously-endemic countries. We used (1) the most recent data for a district, if more than one estimate was available; (2) age- and sex-standardized corrections of historic estimates, where raw data were available; (3) historic estimates adjusted using a mean adjustment factor for districts where raw data were unavailable; and (4) expert assessment of available data for districts for which no prevalence estimates were available. FINDINGS: Internally age- and sex-standardized data represented 1,355 districts and contributed 662 thousand cases (95% confidence interval [CI] 324 thousand-1.1 million) to the global total. Age- and sex-standardized district-level prevalence estimates differed from raw estimates by a mean factor of 0.45 (range 0.03-2.28). Previously non- stratified estimates for 398 districts, adjusted by ×0.45, contributed a further 411 thousand cases (95% CI 283-557 thousand). Eight countries retained previous estimates, contributing 848 thousand cases (95% CI 225 thousand-1.7 million). New expert assessments in 14 countries contributed 862 thousand cases (95% CI 228 thousand-1.7 million). The global trichiasis burden in 2016 was 2.8 million cases (95% CI 1.1-5.2 million). INTERPRETATION: The 2016 estimate is lower than previous estimates, probably due to more and better data; scale-up of trichiasis management services; and reductions in incidence due to lower active trachoma prevalence.
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Salud Global , Triquiasis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Adulto JovenRESUMEN
BACKGROUND: To design appropriate schistosomiasis control programmes that include women and preschool-aged children (PSAC) it is essential to assess their disease profile and the risk factors predisposing them to infection. This study aimed to determine the prevalence of urogenital schistosomiasis and the risk factors of infection among PSAC and their caregivers in an endemic area of Zimbabwe. METHODS: A cross-sectional study involving screening for urogenital schistosomiasis infections and treatment of 860 participants [535 children aged ≤ 5 years and 325 caregivers (≥ 15 years)] was carried out in five communities, namely Chihuri, Mupfure, Chakondora, Nduna and Kaziro, in February 2016. Haematuria was recorded for each participant and urine filtration was performed to determine the presence and infection intensity of Schistosoma haematobium. A pre-tested questionnaire was administered to the caregivers seeking knowledge, practices and perceptions regarding schistosomiasis. Data analysis was performed using descriptive statistics and logistic regression. RESULTS: Overall 132 (15.4%) of the 860 participants had S. haematobium infections. Among these, 61 (18.7%) of the 325 caregivers and 71 (13.3%) of the 535 children were infected. The infection prevalence was significantly different between caregivers and PSAC (χ2 = 4.7040, df = 1, P = 0.030). Children whose caregivers used river water for bathing were more likely to be infected compared to children whose caregivers used protected well water (OR: 2.2, 95% CI: 1.3-3.7). The risks of being infected with schistosomiasis were higher in children whose caregivers were infected compared to children whose caregivers had no infection (AOR: 3.9, 95% CI: 1.7-8.6). In caregivers, those who bathed in river water were at higher risk of schistosomiasis infection compared to those who used water from a protected well (AOR: 3.0, 95% CI: 1.4-6.4). CONCLUSIONS: According to the World Health Organization guidelines, the observed overall prevalence of urogenital schistosomiasis qualifies this area as a moderate risk area requiring mass chemotherapy once every two years. Water contact practices of caregivers, and their perceptions and knowledge regarding schistosomiasis are risk factors for infection in both themselves and PSAC. Thus, disease control efforts targeting caregivers or PSAC should include health education and provision of alternative clean and safe water sources.
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Esquistosomiasis Urinaria/epidemiología , Esquistosomiasis Urinaria/orina , Sistema Urogenital/parasitología , Enfermedades Urológicas/parasitología , Adolescente , Adulto , Animales , Preescolar , Estudios Transversales , Enfermedades Endémicas , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Madres , Recuento de Huevos de Parásitos , Prevalencia , Factores de Riesgo , Población Rural , Schistosoma haematobium , Encuestas y Cuestionarios , Enfermedades Urológicas/epidemiología , Adulto Joven , Zimbabwe/epidemiologíaRESUMEN
BACKGROUND: Schistosomiasis primarily affects poor and neglected communities due to their lack of safe water and sanitation facilities. In an effort to improve intervention strategies, the present study investigated the association of socio-demographic characteristics of women with their existing knowledge, perceptions and practices (KPP) in five urogenital schistosomiasis endemic rural communities in Zimbabwe. METHODS: In February 2016, a cross sectional study was conducted in which 426 women in rural Madziwa area, Shamva District were interviewed using a pretested structured questionnaire seeking their KPP and socio-demographic characteristics. Logistic regression analysis was performed to identify socio-demographic factors associated with the KPP variables. RESULTS: Among the 426 participants, 93.7% knew about schistosomiasis, while 97.7 and 87.5% understood the disease transmission and methods for prevention, respectively. A significantly higher percentage of women aged ≥ 30 years compared to those < 30 years indicated that infertility is a complication of untreated chronic schistosomiasis (OR: 1.7, 95% CI: 0.9-3.0). Compared to women who had no history of infection, those who had been infected before were more likely to think that they were currently infected (OR: 3.7, 95% CI: 2.4-6.0). Bathing in unsafe water sources was more common in non-apostolic compared to apostolic followers (OR: 2.1, 95% CI: 1.2-3.7). Sole use of unsafe water for domestic purposes was significantly higher in uneducated women compared to the educated (OR: 1.8, 95% CI: 1.0-3.1). Compared to women of the Chakondora community, those in Chihuri, Nduna and Kaziro were more likely to know that dysuria is a symptom of schistosomiasis while those in Chihuri were also likely to allow young children to perform water contact activities (OR: 2.9, 95% CI: 1.5-5.5). CONCLUSIONS: Despite the high level of schistosomiasis awareness, some women had inadequate knowledge about the mode of transmission and preventive measures for schistosomiasis. Socio-demographic characteristics were associated with the KPP of women. Thus, disease control efforts should consider socio-demographic factors, which may influence the knowledge, perceptions and practices of occupants in a given setting.