Key traveller groups of relevance to spatial malaria transmission: a survey of movement patterns in four sub-Saharan African countries.

BACKGROUND: As malaria prevalence declines in many parts of the world due to widescale control efforts and as drug-resistant parasites begin to emerge, a quantitative understanding of human movement is becoming increasingly relevant to malaria control. However, despite its importance, significant knowledge gaps remain regarding human movement, particularly in sub-Saharan Africa. METHODS: A quantitative survey of human movement patterns was conducted in four countries in sub-Saharan Africa: Mali, Burkina Faso, Zambia, and Tanzania, with three to five survey locations chosen in each country. Questions were included on demographic and trip details, malaria risk behaviour, children accompanying travellers, and mobile phone usage to enable phone signal data to be better correlated with movement. A total of 4352 individuals were interviewed and 6411 trips recorded. RESULTS: A cluster analysis of trips highlighted two distinct traveller groups of relevance to malaria transmission: women travelling with children (in all four countries) and youth workers (in Mali). Women travelling with children were more likely to travel to areas of relatively high malaria prevalence in Mali (OR = 4.46, 95% CI = 3.42-5.83), Burkina Faso (OR = 1.58, 95% CI = 1.23-1.58), Zambia (OR = 1.50, 95% CI = 1.20-1.89), and Tanzania (OR = 2.28, 95% CI = 1.71-3.05) compared to other travellers. They were also more likely to own bed nets in Burkina Faso (OR = 1.77, 95% CI = 1.25-2.53) and Zambia (OR = 1.74, 95% CI = 1.34 2.27), and less likely to own a mobile phone in Mali (OR = 0.50, 95% CI = 0.39-0.65), Burkina Faso (OR = 0.39, 95% CI = 0.30-0.52), and Zambia (OR = 0.60, 95% CI = 0.47-0.76). Malian youth workers were more likely to travel to areas of relatively high malaria prevalence (OR = 23, 95% CI = 17-31) and for longer durations (mean of 70 days cf 21 days, p < 0.001) compared to other travellers. CONCLUSIONS: Women travelling with children were a remarkably consistent traveller group across all four countries surveyed. They are expected to contribute greatly towards spatial malaria transmission because the children they travel with tend to have high parasite prevalence. Youth workers were a significant traveller group in Mali and are expected to contribute greatly to spatial malaria transmission because their movements correlate with seasonal rains and hence peak mosquito densities. Interventions aimed at interrupting spatial transmission of parasites should consider these traveller groups.

Antibiotic prescribing practices for patients with fever in the transition from presumptive treatment of malaria to 'confirm and treat' in Zambia: a cross-sectional study.

OBJECTIVES: To evaluate antibiotic use among patients presenting to primary healthcare facilities with febrile illness in Zambia. METHODS: We analysed data from a 2011 nationwide cross-sectional health facility survey of routine malaria case management in Zambia. Patient consultation observation and medical record charts were used to calculate the proportion of febrile patients who were prescribed antibiotics, stratified by symptoms, health workers' diagnosis and malaria test results. Logistic regression was used to identify factors affecting antibiotic prescribing behaviour. RESULTS: Of 872 patients presenting with fever, 651 (74.6%) were tested for malaria. Among those tested, 608 (93.4%) had analysable results; 230 (37.8%) had positive results. Antibiotics were prescribed to 69/230 (30.0%), 247/378 (65.3%) and 132/221 (59.7%) of those who tested positive, negative and those 'not tested', respectively. Furthermore, antibiotics were prescribed to 36/59 (61.0%) and 242/322 (75.1%) of those diagnosed with diarrhoea and upper respiratory tract infection (URTI), respectively. Among patients prescribed any antibiotic, concurrent antimalarial prescribing occurred in 66/69 (95.6%), 32/247 (12.9%) and 19/132 (14.4%) for those with positive results, negative results and 'not tested', respectively. Respiratory symptoms, diagnosis of URTI, malaria or skin disease and level of health care in the health delivery system were associated with antibiotic prescribing. CONCLUSIONS: Testing positive for malaria or receiving a malaria diagnosis was associated with reduced antibiotic prescribing, while testing negative, not being tested or a diagnosis of URTI resulted in higher rates of antibiotic prescribing. There is a need for improving diagnostic capacity for non-malaria causes of febrile illness at healthcare delivery points and limiting antibiotic use to patients with definite bacterial infections.

Evaluation of methods for linking household and health care provider data to estimate effective coverage of management of child illness: results of a pilot study in Southern Province, Zambia.

BACKGROUND: Existing population-based surveys have limited accuracy for estimating the coverage and quality of management of child illness. Linking household survey data with health care provider assessments has been proposed as a means of generating more informative population-level estimates of effective coverage, but methodological issues need to be addressed. METHODS: A 2016 survey estimated effective coverage of management of child illness in Southern Province, Zambia, using multiple methods for linking temporally and geographically proximate household and health care provider data. Mothers of children <5 years were surveyed about seeking care for child illness. Information on health care providers' capacity to manage child illness, or structural quality, was assessed using case scenarios and a tool modeled on the WHO Service Availability and Readiness Assessment (SARA). Each sick child was assigned the structural quality score of their stated (exact-match) source of care. Effective coverage was calculated as the average structural quality experienced by all sick children. Children were also ecologically linked to providers using measures of geographic proximity, with and without data on non-facility providers, to assess the effects of these linking methods on effective coverage estimates. RESULTS: Data were collected on 83 providers and 385 children with fever, diarrhea, and/or symptoms of ARI in the preceding 2 weeks. Most children sought care from government facilities or community-based agents (CBAs). Effective coverage of management of child illness estimated through exact-match linking was approximately 15-points lower in each stratum than coverage of seeking skilled care due to providers' limited structural quality. Estimates generated using most measures of geographic proximity were similar to the exact-match estimate, with the exception of the kernel density estimation method in the urban area. Estimates of coverage in rural areas were greatly reduced across all methods using facility-only data if seeking care from CBAs was treated as unskilled care. CONCLUSIONS: Linking household and provider data may generate more informative estimates of effective coverage of management of child illness. Ecological linking with provider data on a sample of all skilled providers may be as effective as exact-match linking in areas with low variation in structural quality within a provider category or minimal provider bypassing.

Validity of maternal report of care-seeking for childhood illness.

BACKGROUND: Accurate data on care-seeking for child illness are needed to improve public health programs and reduce child mortality. The accuracy of maternal report of care-seeking for child illness as collected through household surveys has not been validated. METHODS: A 2016 survey compared reported care-seeking against a gold-standard of health care provider documented care-seeking events among a random sample of mothers of children <5 years in Southern Province, Zambia. Enrolled children were assigned cards with unique barcodes. Seventy-five health care providers were given smartphones with a barcode reader and instructed to scan the cards of participating children seeking care at the source, generating an electronic record of the care-seeking event. Additionally, providers gave all caregivers accessing care for a child <5 years provider-specific tokens used to verify the point of care during the household survey. Reported care-seeking events were ascertained in each household using a questionnaire modeled off the Zambia Demographic and Health Survey (DHS) / Multiple Indicator Cluster Survey (MICS). The accuracy of maternal report of care-seeking behavior was estimated by comparing care-seeking events reported by mothers against provider-documented events. RESULTS: Data were collected on 384 children with fever, diarrhea, and/or symptoms of ARI in the preceding 2 weeks. Most children sought care from government facilities or community-based agents (CBAs). We found high sensitivity (Rural: 0.91, 95% confidence interval CI 0.84-0.95; Urban: 0.98, 95% CI 0.92-0.99) and reasonable specificity (Rural: 0.71, 95% CI 0.57-0.82; Urban: 0.76, 95% CI 0.62-0.85) of maternal report of care-seeking for child illness by type of provider. Maternal report of any care-seeking and seeking care from a skilled provider had slightly higher sensitivity and specificity. Seeking care from a traditional practitioner was associated with lower odds of accurately reporting the event, while seeking care from a government provider was associated with greater odds of accurate report. The measure resulted in a slight overestimation of true care-seeking behavior in the study population. CONCLUSIONS: Maternal report is a valid measure of care-seeking for child illness in settings with high utilization of public sector providers. The study findings were limited by the low diversity in care-seeking practices for child illness and the exclusion of shops.

Effects of Airborne Particulate Matter on Respiratory Health in a Community near a Cement Factory in Chilanga, Zambia: Results from a Panel Study.

We conducted a panel study to investigate seasonal variations in concentrations of airborne PM2.5 and PM10 and the effects on respiratory health in a community near a cement factory; in Chilanga; Zambia. A panel of 63 and 55 participants aged 21 to 59 years from a community located at the edge of the factory within 1 km and a control community located 18 km from the factory respectively; were followed up for three climatic seasons July 2015 to February 2016. Symptom diary questionnaires were completed and lung function measurements taken daily for 14 days in each of the three climatic seasons. Simultaneously, PM2.5 and PM10 concentrations in ambient air were monitored at a fixed site for each community. Mean seasonal concentrations of PM2.5 and PM10 ranged from 2.39-24.93 µg/m3 and 7.03-68.28 µg/m³ respectively in the exposed compared to the control community 1.69-6.03 µg/m³ and 2.26-8.86 µg/m³. The incident rates of reported respiratory symptoms were higher in the exposed compared to the control community: 46.3 vs. 13.8 for cough; 41.2 vs. 9.6 for phlegm; 49.0 vs.12.5 for nose; and 13.9 vs. 3.9 for wheeze per 100 person-days. There was a lower performance on all lung indices in the exposed community compared to the control; overall the mean FEV1 (forced expiratory volume in one second) and FVC (forced vital capacity) predicted percentage for the exposed was six and four percentage points lower than the control. Restriction of industrial emissions coupled with on-going monitoring and regulatory enforcement are needed to ensure that PM (airborne particulate matter) levels in the ambient air are kept within recommended levels to safeguard the respiratory health of nearby community residents.

Prevalence and determinants of mucous membrane irritations in a community near a cement factory in Zambia: a cross sectional study.

Exposure to cement dust has been associated with deleterious health effects in humans. This study investigated whether residing near a cement factory increases the risk of irritations to the mucous membranes of the eyes and respiratory system. A cross sectional study was conducted in Freedom Compound, a community bordering a cement factory in Chilanga, Zambia and a control community, Bauleni, located 18 km from the cement plant. A modified American Thoracic Society questionnaire was administered to 225 and 198 respondents aged 15-59 years from Freedom and Bauleni, respectively, to capture symptoms of the irritations. Respondents from Freedom Compound, were more likely to experience the irritations; adjusted ORs 2.50 (95% CI: 1.65, 3.79), 4.36 (95% CI (2.96, 6.55)) and 1.94 (95% CI (1.19, 3.18)) for eye, nose and sinus membrane irritations respectively. Cohort panel studies to determine associations of cement emissions to mucous membrane irritations and respiratory symptoms, coupled with field characterization of the exposure are needed to assess whether the excess prevalence of symptoms of mucous membrane irritations observed in Freedom compound are due to emissions from the cement factory.