Effect of improved housing on illness in children under 5 years old in northern Malawi: cross sectional study

Malaria epidemiology and comparative reliability of diagnostic tools in Bannu; an endemic malaria focus in south of Khyber Pakhtunkhwa, Pakistan

The present study was aimed at elucidation of malaria epidemiology and comparing performance of several diagnostic procedures in Bannu, a highly endemic district of Khyber Pakhtunkhwa, Pakistan. Dried blood spots were collected from patients suspected of malaria visiting a hospital and two private laboratories in district Bannu and processed for species-specific PCR (rRNA). Patients were also screened for malaria through microscopy and RDT. A well-structured questionnaire was used to collect patient information to assess risk factors for malaria. Of 2033 individuals recruited, 21.1% (N = 429) were positive for malaria by at least one method. Overall, positivity detected by PCR was 30.5% (95/311) followed by 17.7% by microscopy (359/2033) and 16.4% by RDT (266/1618). Plasmodium vivax (16.9%, N = 343) was detected as the dominant species followed by Plasmodium falciparum (2.3%, N = 47) and mixed infections (1.2%, N = 39). Microscopy and RDT (Cohen's kappa k = 0.968, p = <0.0001, McNemar test p = 0.069) displayed significant agreement with each other. Satisfactory health, sleeping indoors, presence of health-care facility in vicinity (at an accessible range from home), living in upper middle class and in concrete houses significantly reduced malaria risk; whereas, low literacy level, presence of domestic animals indoors and malaria diagnosis recommended by clinician increased the disease risk. Overall, findings from the study provide reasonable basis for use of RDT as a cost-effective screening tool in field and for clinicians who can proceed with timely treatment of malaria patients. Appropriate management of identified risk factors could contribute to reduction of malaria prevalence in Bannu and its peripheries.

Improving socioeconomic status may reduce the burden of malaria in sub Saharan Africa: A systematic review and meta-analysis

Background

A clear understanding of the effects of housing structure, education, occupation, income, and wealth on malaria can help to better design socioeconomic interventions to control the disease. This literature review summarizes the relationship of housing structure, educational level, occupation, income, and wealth with the epidemiology of malaria in sub-Saharan Africa (SSA).

Methods

A systematic review and meta-analysis was conducted following the preferred reporting items for systematic reviews and meta-analyses guidelines. The protocol for this study is registered in PROSPERO (ID=CRD42017056070), an international database of prospectively registered systematic reviews. On January 16, 2016, available literature was searched in PubMed, Embase, CINAHL, and Cochrane Library. All but case studies, which reported prevalence or incidence of Plasmodium infection stratified by socioeconomic status among individuals living in SSA, were included without any limits. Odds Ratio (OR) and Relative Risk (RR), together with 95% CI and p-values were used as effect measures. Heterogeneity was assessed using chi-square, Moran’s I², and tau² tests. Fixed (I²<30%), random (I²≥30%) or log-linear dose-response model was used to estimate the summary OR or RR.

Results

After removing duplicates and screening of titles, abstracts, and full text, 84 articles were found eligible for systematic review, and 75 of them were included in the meta-analyses. Fifty-seven studies were cross-sectional, 12 were prospective cohort, 10 were case-control, and five were randomized control trials. The odds of Plasmodium infection increased among individuals who were living in poor quality houses (OR 2.13, 95% CI 1.56–3.23, I² = 27.7), were uneducated (OR 1.36, 95% CI 1.19–1.54, I² = 72.4.0%), and were farmers by occupation (OR 1.48, 95% CI 1.11–1.85, I² = 0.0%) [p<0.01 for all]. The odds of Plasmodium infection also increased with a decrease in the income (OR 1.02, 95% CI 1.01–1.03, tau²<0.001), and wealth index of individuals (OR 1.25, 95% CI 1.18–1.35, tau² = 0.028) [p<0.001 for both]. Longitudinal studies also showed an increased risk of Plasmodium infection among individuals who were living in poor quality houses (RR 1.86, 95% CI 1.47–2.25, I² = 0.0%), were uneducated (OR 1.27, 1.03–1.50, I² = 0.0%), and were farmers (OR 1.36, 1.18–1.58) [p<0.01 for all].

Conclusions

Lack of education, low income, low wealth, living in poorly constructed houses, and having an occupation in farming may increase risk of Plasmodium infection among people in SSA. Public policy measures that can reduce inequity in health coverage, as well as improve economic and educational opportunities for the poor, will help in reducing the burden of malaria in SSA.

Household air pollution (HAP), microenvironment and child health: Strategies for mitigating HAP exposure in urban Rwanda

Exposure to household air pollution (HAP) from cooking and heating with solid fuels is major risk factor for morbidity and mortality in sub-Saharan Africa. Children under five are particularly at risk for acute lower respiratory infection. We use baseline data from randomized controlled trial evaluating a household energy intervention in Gisenyi, Rwanda to investigate the role of the microenvironment as a determinant of children's HAP-related health symptoms. Our sample includes 529 households, with 694 children under five. We examine the association between likelihood of HAP-related health symptom prevalence and characteristics of the microenvironment including: dwelling and cooking area structure; distance to nearest road; and tree cover. We find that children residing in groups of enclosed dwellings, in households that cook indoors, and in households proximate to tree cover, are significantly more likely to experience symptoms of respiratory infection, illness with cough and difficulty breathing. On the other hand, children in households with cemented floors and ventilation holes in the cooking area, are significantly less likely to experience the same symptoms. Our findings suggest that in addition to promoting increased access to clean cooking technologies, there are important infrastructure and micro-environment related interventions that mitigate HAP exposure.

Patterns and determinants of malaria risk in urban and peri-urban areas of Blantyre, Malawi

Background

Although malaria disease in urban and peri-urban areas of sub-Saharan Africa is a growing concern, the epidemiologic patterns and drivers of transmission in these settings remain poorly understood. Factors associated with variation in malaria risk in urban and peri-urban areas were evaluated in this study.

Methods

A health facility-based, age and location-matched, case–control study of children 6–59 months of age was conducted in four urban and two peri-urban health facilities (HF) of Blantyre city, Malawi. Children with fever who sought care from the same HF were tested for malaria parasites by microscopy and PCR. Those testing positive or negative on both were defined as malaria cases or controls, respectively.

Results

A total of 187 cases and 286 controls were studied. In univariate analyses, higher level of education, possession of TV, and electricity in the house were negatively associated with malaria illness; these associations were similar in urban and peri-urban zones. Having travelled in the month before testing was strongly associated with clinical malaria, but only for participants living in the urban zones (OR = 5.1; 95% CI = 1.62, 15.8). Use of long-lasting insecticide nets (LLINs) the previous night was not associated with protection from malaria disease in any setting. In multivariate analyses, electricity in the house, travel within the previous month, and a higher level of education were all associated with decreased odds of malaria disease. Only a limited number of Anopheles mosquitoes were found by aspiration inside the households in the peri-urban areas, and none was collected from the urban households.

Conclusion

Travel was the main factor influencing the incidence of malaria illness among residents of urban Blantyre compared with peri-urban areas. Identification and understanding of key mobile demographic groups, their behaviours, and the pattern of parasite dispersal is critical to the design of more targeted interventions for the urban setting.

Electronic supplementary material

The online version of this article (doi:10.1186/s12936-016-1623-9) contains supplementary material, which is available to authorized users.

The independent effect of living in malaria hotspots on future malaria infection: an observational study from Misungwi, Tanzania

BACKGROUND

As malaria transmission declines, continued improvements of prevention and control interventions will increasingly rely on accurate knowledge of risk factors and an ability to define high-risk areas and populations at risk for focal targeting of interventions. This paper explores the independent association between living in a hotspot and prospective risk of malaria infection.

METHODS

Malaria infection status defined by nPCR and AMA-1 status in year 1 were used to define geographic hotspots using two geospatial statistical methods (SaTScan and Kernel density smoothing). Other malaria risk factors for malaria infection were explored by fitting a multivariable model.

RESULTS

This study demonstrated that residing in infection hotspot of malaria transmission is an independent predictor of malaria infection in the future.

CONCLUSION

It is likely that targeting such hotspots with better coverage and improved malaria control strategies will result in more cost-efficient uses of resources to move towards malaria elimination.

Is housing quality associated with malaria incidence among young children and mosquito vector numbers? Evidence from Korogwe, Tanzania

Background

Several studies conducted in Northeast Tanzania have documented declines in malaria transmission even before interventions were scaled up. One explanation for these reductions may be the changes in socio-environmental conditions associated with economic development, and in particular improvements in housing construction.

Objective

This analysis seeks to identify (1) risk factors for malaria incidence among young children and (2) household and environmental factors associated with mosquito vector numbers collected in the child’s sleeping area. Both analyses focus on housing construction quality as a key determinant.

Methodology

For 435 children enrolled in a larger trial of intermittent preventive treatment for malaria in infants in the Korogwe District in Tanga, Northeastern Tanzania, detailed information on their dwelling characteristics were collected in the last year of the trial. Principal components analysis was used to construct an index of housing structure quality and converted to quintile units for regression analysis. Univariate and multivariate random effects negative binomial regressions were used to predict risk factors for child malaria incidence and the mean total number of indoor female Anopheles gambiae and funestus mosquitoes collected per household across three occasions.

Findings

Building materials have substantially improved in Korogwe over time. Multivariate regressions showed that residing in rural areas (versus urban) increased malaria incidence rates by over three-fold and mean indoor female A. gambiae and funestus numbers by nearly two-fold. Compared to those residing in the lowest quality houses, children residing in the highest quality houses had one-third lower malaria incidence rates, even when wealth and rural residence were controlled for. Living in the highest quality houses reduced vector numbers while having cattle near the house significantly increased them.

Conclusions

Results corroborate findings from other studies that show associations between malaria incidence and housing quality; associations were concentrated amongst the highest quality houses.

Economic analysis of the health impacts of housing improvement studies: a systematic review

BACKGROUND

Economic evaluation of public policies has been advocated but rarely performed. Studies from a systematic review of the health impacts of housing improvement included data on costs and some economic analysis. Examination of these data provides an opportunity to explore the difficulties and the potential for economic evaluation of housing.

METHODS

Data were extracted from all studies included in the systematic review of housing improvement which had reported costs and economic analysis (n=29/45). The reported data were assessed for their suitability to economic evaluation. Where an economic analysis was reported the analysis was described according to pre-set definitions of various types of economic analysis used in the field of health economics.

RESULTS

25 studies reported cost data on the intervention and/or benefits to the recipients. Of these, 11 studies reported data which was considered amenable to economic evaluation. A further four studies reported conducting an economic evaluation. Three of these studies presented a hybrid 'balance sheet' approach and indicated a net economic benefit associated with the intervention. One cost-effectiveness evaluation was identified but the data were unclearly reported; the cost-effectiveness plane suggested that the intervention was more costly and less effective than the status quo.

CONCLUSIONS

Future studies planning an economic evaluation need to (i) make best use of available data and (ii) ensure that all relevant data are collected. To facilitate this, economic evaluations should be planned alongside the intervention with input from health economists from the outset of the study. When undertaken appropriately, economic evaluation provides the potential to make significant contributions to housing policy.

Housing improvements for health and associated socio-economic outcomes

BACKGROUND

The well established links between poor housing and poor health indicate that housing improvement may be an important mechanism through which public investment can lead to health improvement. Intervention studies which have assessed the health impacts of housing improvements are an important data resource to test assumptions about the potential for health improvement. Evaluations may not detect long term health impacts due to limited follow-up periods. Impacts on socio-economic determinants of health may be a valuable proxy indication of the potential for longer term health impacts.

OBJECTIVES

To assess the health and social impacts on residents following improvements to the physical fabric of housing.

SEARCH METHODS

Twenty seven academic and grey literature bibliographic databases were searched for housing intervention studies from 1887 to July 2012 (ASSIA; Avery Index; CAB Abstracts; The Campbell Library; CINAHL; The Cochrane Library; COPAC; DH-DATA: Health Admin; EMBASE; Geobase; Global Health; IBSS; ICONDA; MEDLINE; MEDLINE In-Process & Other Non-Indexed Citations; NTIS; PAIS; PLANEX; PsycINFO; RIBA; SCIE; Sociological Abstracts; Social Science Citations Index; Science Citations Index expanded; SIGLE; SPECTR). Twelve Scandinavian grey literature and policy databases (Libris; SveMed+; Libris uppsök; DIVA; Artikelsök; NORART; DEFF; AKF; DSI; SBI; Statens Institut for Folkesundhed; Social.dk) and 23 relevant websites were searched. In addition, a request to topic experts was issued for details of relevant studies. Searches were not restricted by language or publication status.

SELECTION CRITERIA

Studies which assessed change in any health outcome following housing improvement were included. This included experimental studies and uncontrolled studies. Cross-sectional studies were excluded as correlations are not able to shed light on changes in outcomes. Studies reporting only socio-economic outcomes or indirect measures of health, such as health service use, were excluded. All housing improvements which involved a physical improvement to the fabric of the house were included. Excluded interventions were improvements to mobile homes; modifications for mobility or medical reasons; air quality; lead removal; radon exposure reduction; allergen reduction or removal; and furniture or equipment. Where an improvement included one of these in addition to an included intervention the study was included in the review. Studies were not excluded on the basis of date, location, or language.

DATA COLLECTION AND ANALYSIS

Studies were independently screened and critically appraised by two review authors. Study quality was assessed using the risk of bias tool and the Hamilton tool to accommodate non-experimental and uncontrolled studies. Health and socio-economic impact data were extracted by one review author and checked by a second review author. Studies were grouped according to broad intervention categories, date, and context before synthesis. Where possible, standardized effect estimates were calculated and statistically pooled. Where meta-analysis was not appropriate the data were tabulated and synthesized narratively following a cross-study examination of reported impacts and study characteristics. Qualitative data were summarized using a logic model to map reported impacts and links to health impacts; quantitative data were incorporated into the model.

MAIN RESULTS

Thirty-nine studies which reported quantitative or qualitative data, or both, were included in the review. Thirty-three quantitative studies were identified. This included five randomised controlled trials (RCTs) and 10 non-experimental studies of warmth improvements, 12 non-experimental studies of rehousing or retrofitting, three non-experimental studies of provision of basic improvements in low or mIddle Income countries (LMIC), and three non-experimental historical studies of rehousing from slums. Fourteen quantitative studies (42.4%) were assessed to be poor quality and were not included in the synthesis. Twelve studies reporting qualitative data were identified. These were studies of warmth improvements (n = 7) and rehousing (n = 5). Three qualitative studies were excluded from the synthesis due to lack of clarity of methods. Six of the included qualitative studies also reported quantitative data which was included in the review.Very little quantitative synthesis was possible as the data were not amenable to meta-analysis. This was largely due to extreme heterogeneity both methodologically as well as because of variations in the intervention, samples, context, and outcome; these variations remained even following grouping of interventions and outcomes. In addition, few studies reported data that were amenable to calculation of standardized effect sizes. The data were synthesised narratively.Data from studies of warmth and energy efficiency interventions suggested that improvements in general health, respiratory health, and mental health are possible. Studies which targeted those with inadequate warmth and existing chronic respiratory disease were most likely to report health improvement. Impacts following housing-led neighbourhood renewal were less clear; these interventions targeted areas rather than individual households in most need. Two poorer quality LMIC studies reported unclear or small health improvements. One better quality study of rehousing from slums (pre-1960) reported some improvement in mental health. There were few reports of adverse health impacts following housing improvement. A small number of studies gathered data on social and socio-economic impacts associated with housing improvement. Warmth improvements were associated with increased usable space, increased privacy, and improved social relationships; absences from work or school due to illness were also reduced.Very few studies reported differential impacts relevant to equity issues, and what data were reported were not amenable to synthesis.

AUTHORS' CONCLUSIONS

Housing investment which improves thermal comfort in the home can lead to health improvements, especially where the improvements are targeted at those with inadequate warmth and those with chronic respiratory disease. The health impacts of programmes which deliver improvements across areas and do not target according to levels of individual need were less clear, but reported impacts at an area level may conceal health improvements for those with the greatest potential to benefit. Best available evidence indicates that housing which is an appropriate size for the householders and is affordable to heat is linked to improved health and may promote improved social relationships within and beyond the household. In addition, there is some suggestion that provision of adequate, affordable warmth may reduce absences from school or work.While many of the interventions were targeted at low income groups, a near absence of reporting differential impacts prevented analysis of the potential for housing improvement to impact on social and economic inequalities.

Housing conditions of home-based care patients in Botswana and the implications for HIV care

People living with HIV or with a terminal disease face frequent health risks due to opportunistic infections which affect their way of life and dramatically increase their risk of death. Increasingly, terminally ill patients in Botswana are cared for at home, hence the need to understand their housing conditions. Despite a high volume of HIV-related studies undertaken in Botswana, little research has examined the relationship between patients' housing conditions and quality of care at home. Using existing government data from the Botswana 2001 Population and Housing Census, we investigated the housing situation for the households in the national home-based care (HBC) programme. Data were available for 8 872 households having residents enrolled in the programme. The findings indicate that the majority of patients under HBC are faced with housing-related features that can affect their quality of care and chances of recovery. The largest proportion of households had six or more individuals sharing one or two rooms, which raises health concerns for the spread of communicable diseases. In rural areas, few of the HBC households had indoor piped water, proper waste disposal or flush toilets. The lack of basic amenities such as these creates problems for patients as well as for caregivers. We advocate for policy that will address and cater to housing as part of a comprehensive and effective HBC programme. Housing determines where, how and when homecare is provided for sick individuals; therefore, achieving healthy living environments and housing assistance for HBC patients must be addressed by the government. It is recommended that an evaluation of a patient's home should be a first step in their enrolment in the HBC programme. Thereafter, HIV-infected or affected household members should be advised and assisted to make the necessary housing changes to maintain quality of life or accelerate the homecare patient's recovery.

Public health status and influence factors after 2008 Wenchuan earthquake among survivors in Sichuan province, China: cross-sectional trial

OBJECTIVES

On 12 May 2008, an earthquake with a magnitude of 8.0 on the Richter scale struck in Sichuan province, China. After the disaster, approximately 5 million people were living in temporary shelters. The objectives of this study were: (1) to provide the basic information on public health outcomes among the survivors; (2) to compare these outcomes between counties affected to differing extents by the earthquake; and (3) to identify important policies and programmes associated with public health outcomes.

STUDY DESIGN

Cross-sectional multicluster sample surveys were employed using data collected from two counties.

METHODS

Cross-sectional surveys were conducted in August 2008 in two counties in Sichuan province. The study outcomes [physical component summary (PCS) and mental component summary (MCS)] were measured using Short Form-12. Independent demographic, socio-economic and trauma exposure variables were also measured. Multivariate regression analysis was conducted to investigate associations between the independent variables and PCS and MCS outcomes.

RESULTS

In total, 3862 interviews were completed in the two counties. The mean PCS score was 37.6 [95% confidence interval (95% CI 35.13-41.97) in Beichuan county and 45.4 (95% CI 44.30-45.95) in Langzhong county. MCS scores were 36.8 (95% CI 33.61-40.71) in Beichuan county and 49.6 (95% CI 49.69-50.01) in Langzhong county, well below the instrument norm of 50. Variables with negative associations with physical or mental health included: female gender, living in a temporary shelter, higher income, deaths among family/friends, family property damaged and illness within the past 2 weeks. Higher frequencies of trauma exposure (more than six trauma exposure events) showed a strong significant negative association with PCS and MCS in both counties.

CONCLUSIONS

Interventions should be designed to focus on people without a household income (or a lower income), living in shelters or temporary houses. Governments should support income-generating activities and improve living conditions and public health status.

The health impacts of housing improvement: a systematic review of intervention studies from 1887 to 2007

OBJECTIVES

We conducted a systematic review of the health impacts of housing improvement.

METHODS

Forty-two bibliographic databases were searched for housing intervention studies from 1887 to 2007. Studies were appraised independently by H. T. and S. T. or E. S. for sources of bias. The data were tabulated and synthesized narratively, taking into account study quality.

RESULTS

Forty-five relevant studies were identified. Improvements in general, respiratory, and mental health were reported following warmth improvement measures, but these health improvements varied across studies. Varied health impacts were reported following housing-led neighborhood renewal. Studies from the developing world suggest that provision of basic housing amenities may lead to reduced illness. There were few reports of adverse health impacts following housing improvement. Some studies reported that the housing improvement was associated with positive impacts on socioeconomic determinants of health.

CONCLUSIONS

Housing improvements, especially warmth improvements, can generate health improvements; there is little evidence of detrimental health impacts. The potential for health benefits may depend on baseline housing conditions and careful targeting of the intervention. Investigation of socioeconomic impacts associated with housing improvement is needed to investigate the potential for longer-term health impacts.

When home is where the stress is: expanding the dimensions of housing that influence asthma morbidity

The influence of physical housing quality on childhood asthma expression, especially the effect of exposure to moulds, allergens, and pollutants, is well documented. However, attempts to explain increasing rates and severity of childhood asthma solely through physical environmental factors have been unsuccessful, and additional exposures may be involved. Increasing evidence has linked psychological stress and negative affective states to asthma expression. At the same time, recent scholarship in the social sciences has focused on understanding how social environments, such as housing, "get under the skin" to influence health, and suggests that psychological factors play a key role. While there is relevant overlapping research in social science, psychology, economics, and health policy in this area, findings from these disciplines have not yet been conceptually integrated into ongoing asthma research. We propose to expand the dimensions of housing considered in future asthma research to include both physical and psychological aspects which may directly and indirectly influence onset and severity of disease expression. This synthesis of overlapping research from a number of disciplines argues for the systematic measure of psychological dimensions of housing and consideration of the interplay between housing stress and physical housing characteristics in relation to childhood asthma.

Harboring illnesses: on the association between disease and living conditions in a Palestinian refugee camp in Lebanon

This research examined the association between the domestic built environment in a Palestinian refugee camp in Beirut, Lebanon, and the presence of illness among household members. Data on the domestic built environment, socio-demographics and health were collected in 860 households. The association between the presence of illness among household members and three environmental indices, namely infrastructure and services, housing conditions, and crowding was evaluated. These indices were based on a number of items that reflected the existing problems in the domestic built environment. The main finding was the positive association between poor housing conditions and the presence of illness among household members. Households with 8 - 15 housing problems were twice more likely to report the presence of illness than those with less than four housing problems (OR=2.08, 95% CI=1.40 - 3.11). This research contributes to the understanding of the influence of the built environment on the health of a refugee population.

Reducing the burden of malaria in different eco-epidemiological settings with environmental management: a systematic review

The public health and economic significance of malaria is enormous, and its control remains a great challenge. Many established malaria control methods are hampered by drug resistance and insecticide-resistant vectors. Malaria control measures built around environmental management are non-toxic, cost-effective, and sustainable. However, there has been no comprehensive review of the literature or meta-analysis examining the effect of these interventions. We therefore did a systematic literature review and identified 40 studies that emphasised environmental management interventions and reported clinical malaria variables as outcome measures. Of these 40 studies, environmental modification (measures aiming to create a permanent or long-lasting effect on land, water, or vegetation to reduce vector habitats--eg, the installation and maintenance of drains) was the central feature in 27 studies, environmental manipulation (methods creating temporary unfavourable conditions for the vector--eg, water or vegetation management) in four, and nine quantified the effect of modifications of human habitation. Most of the studies (n=34, 85%) were implemented before the Global Malaria Eradication Campaign (1955-69), which mainly relied on indoor residual spraying with dichlorodiphenyltrichloroethane (DDT). In 16 studies that applied environmental modification and in eight studies on modification of human habitation, the risk ratio of malaria was reduced by 88.0% (95% CI 81.7-92.1) and 79.5% (95% CI 67.4-87.2), respectively. We conclude that malaria control programmes that emphasise environmental management are highly effective in reducing morbidity and mortality. Lessons learned from these past successful programmes can inspire sound and sustainable malaria control approaches and strategies.

The effects of housing interventions on child health

Housing hazards contribute to considerable morbidity and mortality among millions of children each year in the US, but few interventions are proven to control asthma and lead poisoning. Moreover, there is little evidence that many of the current recommendations to control residential hazards are safe and efficacious. The only interventions that have been found to work consistently are home visitation programs and home modification, such as installment of window guards and carpet removal. Altering the environment to protect the health of children requires pediatrician intervention. New models of cooperation between pediatricians and public health agencies must deal with residential hazards in an integrated manner and cannot be focused on one disease process or one method at a time. With research in more effective environmental interventions and pediatric-public-health partnerships, primary and secondary prevention of diseases from residential hazards may become a reality in the future.