Impact of floods on undernutrition among children under five years of age in low- and middle-income countries: a systematic review.

BACKGROUND: Weather and climate-related disasters, including floods, impact undernutrition through multiple pathways, including food security, inadequate child care practices, and water and sanitation. This review aimed to provide systematic evidence of the impact of floods on undernutrition in children under five years of age in Low and Middle-income countries (LMICs). METHODS: We searched PubMed, Web of Science, Embase, MEDLINE, CINAHL and Scopus for peer-reviewed articles. Popline, WHO Library database (WHOLIS), the International Disaster database (EM-DAT), Food and Agriculture Organisation (FAO), UNICEF and Eldis were searched for grey literature articles. Database searches were first conducted in 2016 and updated in 2020. We included English language articles that reported the effect of floods on undernutrition outcomes in children under 5 years of age in LMICs, without limitation to study design and year of publication. The quality of selected studies was assessed using the National Institutes of Health (NIH) tool for Observational Cohort and Cross-Sectional Studies. RESULTS: Of the 5701 articles identified, 14 met our inclusion criteria. The review noted stunting as the most frequently reported significant form of undernutrition in flood-affected areas. Severe and recurrent floods showed the greatest impact on undernutrition. Due to weak and limited evidence, the study is inconclusive on the most significant forms within the short-term and intermediate periods following floods. On the other hand, stunting was noted as the most frequently reported significant form of undernutrition in the long-term period following floods. There was generally little evidence of the effect of floods on micronutrient deficiencies. Factors associated with child undernutrition in the flood-affected areas included age, gender, diarrhoea, maternal and paternal education, maternal age, household size, land ownership and socioeconomic status. Overall, the quality of the evidence was fairly weak, with the main challenge lying in the inability of the studies to establish causal pathways for the observed effects. CONCLUSIONS: The review suggests clear plans and strategies for preventing and reducing the long-term impact of floods on undernutrition in children under five years. Future research utilising long-term prospective data is indispensable to provide more robust evidence to guide better prevention measures, response decisions and interventions.

Trends of overweight and obesity among preschool children from 2013 to 2018: a cross-sectional study in Rhine-Neckar County and the City of Heidelberg, Germany.

BACKGROUND: Early childhood overweight and obesity is a growing public health concern worldwide. Few recent studies have addressed how time trends varied by sociodemographic characteristics at the regional level using large and high-quality data. This study determines how time trends vary in the prevalence of early childhood overweight and obesity by age, gender, and migration background at the regional level. METHODS: We used a Kernel-density curve to describe the BMI distribution, and evaluated the trends of overweight and obesity by age, gender, and migration background using logistic regression. RESULTS: Mean BMI and the overall prevalence of overweight and obesity increased among preschool children aged 4-6 years in the Rhine-Neckar County and the City of Heidelberg. After adjusting for age, sex, and migration background, trends of overweight significantly increased only among male children in the age 5 year group with migration background (P < 0.05), and an upward trend of obesity was observed only among male children in the age 5 year group and female children in the age 6 year group with migration background (P < 0.05). CONCLUSIONS: BMI distribution as well as general prevalence of overweight and obesity are still increasing among preschool children. Children with migration backgrounds, particularly male children in the age 5 year groups and female children in the age 6 year group should be prioritized. Health promotion strategies for children with migration backgrounds will help address this challenge.

Associations between BMI and visual impairment of 33 407 preschool children in Germany: a pooled cross-sectional study.

BACKGROUND: Prevalence of overweight and obesity in Germany is increasing. High body weight can affect children's growth and development. This paper aimed to determine the association between body mass index (BMI) and visual impairment among preschool children and explore the potential role of obesity in predicting visual developmental disorder. METHODS: Six consecutive years of data from the School Entry Examination were collected for all preschool children aged from 4 to 6 years residing in Rhine-Neckar County and the City of Heidelberg, Germany from 2013 to 2018. Univariate and multivariate regression were used to analyze the complete data, multiple imputation was used to deal with missing data. RESULTS: Among the group with an immigrant background, children with obesity [OR = 1.20, 99% (1.02-1.42)] were more likely to have visual impairment compared to those with normal body weight (P < 0.01) after adjusting for survey year, age, and gender of children, education and occupation of parents, screen time-frequency, whether a television was in their bedroom, and quality of preschool outdoor environment. CONCLUSION: There were significant associations between obesity and visual impairment among German preschool children with immigrant backgrounds. Strategies to support vulnerable groups were needed across all regional schools.

Socio-demographic characteristics and risk factors for HIV transmission in female bar workers in sub-Saharan Africa: a systematic literature review.

BACKGROUND: Although sex workers are considered a key population in the HIV epidemic in sub-Saharan Africa (SSA), less consideration has been given to female bar workers (FBW), whose primary occupation is not sex work but who often engage in transactional sex. Understanding FBWs' risk profiles is central to designing targeted HIV prevention interventions for them. This systematic review describes the socio-demographic characteristics and risk factors for HIV transmission among FBWs in SSA. METHODS: We searched six databases: PubMed, Google Scholar, Web of Science, Popline, Embase and additionally the World Health Organization's WHOLIS database for grey literature between July and September 2017. Inclusion criteria were reporting (1) primary socio-demographic or behavioral data; on (2) women who sold or delivered drinks to clients; (3) in establishments serving alcohol; (4) in SSA. We excluded studies not presenting separate data on FBWs. We extracted quantitative and qualitative data from the selected studies and conducted a qualitative synthesis of findings. RESULTS: We found 4565 potentially eligible articles, including duplicates. After applying inclusion and exclusion criteria, we retained 19 articles. FBWs often migrated from rural to urban areas due to economic need or social marginalization. They began bar-based transactional sex due to low wages, peer pressure and to increase financial independence. FBWs had high HIV risk awareness but low agency to negotiate condom use, particularly with regular partners or when offered higher prices for condomless sex. FBWs were also vulnerable to violence and stigmatization. CONCLUSIONS: FBWs are a vulnerable population for HIV infection. Despite social stigmatization and elevated risk of contracting STIs, bar work remains attractive because it enables unskilled women to both, make a living and maintain some independence. FBWs face HIV-related risk factors at the individual, community and societal level and may benefit from biomedical, behavioral and structural interventions.

Reduction of malaria vector mosquitoes in a large-scale intervention trial in rural Burkina Faso using Bti based larval source management.

BACKGROUND: Malaria remains one of the most important causes of morbidity and death in sub-Saharan Africa. Along with early diagnosis and treatment of malaria cases and intermittent preventive treatment in pregnancy (IPTp), vector control is an important tool in the reduction of new cases. Alongside the use of long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS), targeting the vector larvae with biological larvicides, such as Bacillus thuringiensis israelensis (Bti) is gaining importance as a means of reducing the number of mosquito larvae before they emerge to their adult stage. This study presents data corroborating the entomological impact of such an intervention in a rural African environment. METHODS: The study extended over 2 years and researched the impact of biological larviciding with Bti on malaria mosquitoes that were caught indoors and outdoors of houses using light traps. The achieved reductions in female Anopheles mosquitoes were calculated for two different larviciding choices using a regression model. RESULTS: In villages that received selective treatment of the most productive breeding sites, the number of female Anopheles spp. dropped by 61% (95% CI 54-66%) compared to the pre-intervention period. In villages in which all breeding sites were treated, the number of female Anopheles spp. was reduced by 70% (95% CI 64-74%) compared to the pre-intervention period. CONCLUSION: It was shown that malaria vector abundance can be dramatically reduced through larviciding of breeding habitats and that, in many geographical settings, they are a viable addition to current malaria control measures.

Structural, interpersonal, psychosocial, and behavioral risk factors for HIV acquisition among female bar workers in Dar es Salaam, Tanzania.

In sub-Saharan Africa, female bar workers (FBWs) often serve as informal sex workers. Little is known about the prevalence of HIV and HIV-related risk factors among FBWs in Dar es Salaam (DSM), Tanzania. Using an adapted Structural HIV Determinants Framework, we identified structural, interpersonal, psychosocial, and behavioral risk factors for HIV acquisition. We compared the prevalence of HIV and HIV-related risk factors among a random sample of 66 FBWs from DSM to an age-standardized, representative sample of female DSM-residents from the 2016 Demographic and Health and 2011-2012 AIDS Indicator Surveys. Compared to other women in DSM, FBWs had elevated prevalence of all four groups of risk factors. Key risk factors included gender and economic inequalities (structural); sexual violence and challenges negotiating condom use (interpersonal); depression, post-traumatic stress disorder, and low social support (psychosocial); and history of unprotected sex, multiple sex partners, and high alcohol consumption (behavioral). HIV prevalence did not differ between FBWs (7.1%, 95% CI 3.7-13.3%) and survey respondents (7.7%, 95% CI: 5.3-11.1%), perhaps due to FBWs' higher - though sub-optimal - engagement with HIV prevention strategies. Elevated exposure to HIV-related risk factors but low HIV prevalence suggests economic, psychosocial, and biomedical interventions may prevent HIV among FBWs in DSM.

A qualitative study of community perception and acceptance of biological larviciding for malaria mosquito control in rural Burkina Faso.

BACKGROUND: Vector and malaria parasite's rising resistance against pyrethroid-impregnated bed nets and antimalarial drugs highlight the need for additional control measures. Larviciding against malaria vectors is experiencing a renaissance with the availability of environmentally friendly and target species-specific larvicides. In this study, we analyse the perception and acceptability of spraying surface water collections with the biological larvicide Bacillus thuringiensis israelensis in a single health district in Burkina Faso. METHODS: A total of 12 focus group discussions and 12 key informant interviews were performed in 10 rural villages provided with coverage of various larvicide treatments (all breeding sites treated, the most productive breeding sites treated, and untreated control). RESULTS: Respondents' knowledge about the major risk factors for malaria transmission was generally good. Most interviewees stated they performed personal protective measures against vector mosquitoes including the use of bed nets and sometimes mosquito coils and traditional repellents. The acceptance of larviciding in and around the villages was high and the majority of respondents reported a relief in mosquito nuisance and malarial episodes. There was high interest in the project and demand for future continuation. CONCLUSION: This study showed that larviciding interventions received positive resonance from the population. People showed a willingness to be involved and financially support the program. The positive environment with high acceptance for larviciding programs would facilitate routine implementation. An essential factor for the future success of such programs would be inclusion in regional or national malaria control guidelines.

Decreasing child mortality, spatial clustering and decreasing disparity in North-Western Burkina Faso.

Within relatively small areas, there exist high spatial variations of mortality between villages. In rural Burkina Faso, with data from 1993 to 1998, clusters of particularly high child mortality were identified in the population of the Nouna Health and Demographic Surveillance System (HDSS), a member of the INDEPTH Network. In this paper, we report child mortality with respect to temporal trends, spatial clustering and disparity in this HDSS from 1993 to 2012. Poisson regression was used to describe village-specific child mortality rates and time trends in mortality. The spatial scan statistic was used to identify villages or village clusters with higher child mortality. Clustering of mortality in the area is still present, but not as strong as before. The disparity of child mortality between villages has decreased. The decrease occurred in the context of an overall halving of child mortality in the rural area of Nouna HDSS between 1993 and 2012. Extrapolated to the Millennium Development Goals target period 1990-2015, this yields an estimated reduction of 54%, which is not too far off the aim of a two-thirds reduction.

Routine implementation costs of larviciding with Bacillus thuringiensis israelensis against malaria vectors in a district in rural Burkina Faso.

BACKGROUND: The key tools in malaria control are early diagnosis and treatment of cases as well as vector control. Current strategies for malaria vector control in sub-Saharan Africa are largely based on long-lasting insecticide-treated nets (LLINs) and to a much smaller extent on indoor residual spraying (IRS). An additional tool in the fight against malaria vectors, larval source management (LSM), has not been used in sub-Saharan Africa on a wider scale since the abandonment of environmental spraying of DDT. Increasing concerns about limitations of LLINs and IRS and encouraging results from large larvicide-based LSM trials make a strong case for using biological larviciding as a complementary tool to existing control measures. Arguments that are often quoted against such a combined approach are the alleged high implementation costs of LSM. This study makes the first step to test this argument. The implementation costs of larval source management based on Bacillus thuringiensis israelensis (Bti) (strain AM65-52) spraying under different implementation scenarios were analysed in a rural health district in Burkina Faso. METHODS: The analysis draws on detailed cost data gathered during a large-scale LSM intervention between 2013 and 2015. All 127 villages in the study setup were assigned to two treatment arms and one control group. Treatment either implied exhaustive spraying of all available water collections or targeted spraying of the 50 % most productive larval sources via remote-sensing derived and entomologically validated risk maps. Based on the cost reports from both intervention arms, the per capita programme costs were calculated under the assumption of covering the whole district with either intervention scenario. Cost calculations have been generalized by providing an adaptable cost formula. In addition, this study assesses the sensitivity of per capita programme costs with respect to changes in the underlying cost components. RESULTS: The average annual per capita costs of exhaustive larviciding with Bti during the main malaria transmission period (June-October) in the Nouna health district were calculated to be US$ 1.05. When targeted spraying of the 50 % most productive larval sources is used instead, average annual per capita costs decrease by 27 % to US$ 0.77. Additionally, a high sensitivity of per capita programme costs against changes in total surface of potential larval sources and the number of spraying repetitions was found. DISCUSSION: The per capita costs for larval source management interventions with Bti are roughly a third of the annual per capita expenditures for anti-malarial drugs and those for LLINs in Burkina Faso which are US$ 3.80 and 3.00, respectively. The average LSM costs compare to those of IRS and LLINs for sub-Saharan Africa. The authors argue that in such a setting LSM based on Bti spraying is within the range of affordable anti-malarial strategies and, consequently, should deserve more attention in practice. Future research includes a cost-benefit calculation, based on entomological and epidemiological data collected during the research project.

Challenges of implementing a large scale larviciding campaign against malaria in rural Burkina Faso - lessons learned and recommendations derived from the EMIRA project.

BACKGROUND: Recent malaria control and elimination attempts show remarkable success in several parts of sub-Saharan Africa. Vector control via larval source management represents a new and to date underrepresented approach in low income countries to further reduce malaria transmission. Although the positive impact of such campaigns on malaria incidence has been researched, there is a lack of data on which prerequisites are needed for implementing such programs on a routine basis on large scale. Our objectives are to point out important steps in implementing an anti-malaria larviciding campaign in a resource and infrastructure restraint setting and share the lessons learned from our experience during a three-year intervention study in rural Burkina Faso. METHODS: We describe the approaches we followed and the challenges that have been encountered during the EMIRA project, a three-year study on the impact of environmental larviciding on vector ecology and human health. An inventory of all performed work packages and associated problems and peculiarities was assembled. RESULTS: Key to the successful implementation of the larviciding program within a health district was the support and infrastructure from the local research center run by the government. This included availability of trained scientific personnel for local project management, data collection and analysis by medical personnel, entomologists and demographers and teams of fieldworkers for the larviciding intervention. A detailed a priori assessment of the environment and vector breeding site ecology was essential to calculate personnel requirements and the need for larvicide and application apparel. In our case of a three-year project, solid funding for the whole duration was an important issue, which restricted the number of possible donors. We found the acquisition of qualified field personnel in fair numbers not to be always easy and training in application techniques and basic entomologic knowledge required several weeks of theoretical and practical formation. A further crucial point was to establish an effective quality control system that ensured the timely verification of larviciding success and facilitated in time data handling. While the experiences of running a larviciding campaign may vary globally, the experiences gained and the methods used in the Nouna health district may be employed in similar settings. CONCLUSIONS: Our observations highlight important components and strategies that should be taken into account when planning and running a similar larviciding program against malaria in a resource limited setting. A strong local partnership, meticulous planning with the possibility of ad-hoc adaption of project components and a reliable source of funding turned out to be crucial factors to successfully accomplish such a project.