The use of Mobile Phones in Strengthening Health and Demographic Data Collection by Community key Informants : Experiences from the Kintampo Health and Demographic Surveillance System

Identification and reporting of vital events such as births and deaths remain a challenge within communities in low- and middle-income countries (LMICs). LMICs are recently experiencing high mobile phone penetration. This study, therefore, explored the feasibility of Community Key Informants (CKIs) using mobile phone technology to improve reporting of vital events at the community level. Sixty CKIs were purposively sampled from the Kintampo Health and Demographic Surveillance System (KHDSS) setting based on mobile phone ownership. CKIs were grouped into an intervention and a control group. The intervention arm was provided with mobile phone air time to report vital events that occurred in their communities. The control group used the routine system of reporting in the KHDSS. The number of vital events reported by CKIs increased at the end line compared to baseline: (pregnancy: 40.25% to 72.80%; birth: 56.52% to 69.80%; deaths: 33.33% to 68.60%). The time interval between event identification and reporting was much shorter for the intervention group at the end line compared to baseline: (Intervention: 95.06 days to 31.35 days, Control: 87.54 days to 80.57 days). This study demonstrated the feasibility of CKIs using a mobile phone in reporting vital events more timely and effectively.

Mortality in rural coastal Kenya measured using the Kilifi Health and Demographic Surveillance System: a 16-year descriptive analysis

Background: The Kilifi Health and Demographic Surveillance System (KHDSS) was established in 2000 to define the incidence and prevalence of local diseases and evaluate the impact of community-based interventions. KHDSS morbidity data have been reported comprehensively but mortality has not been described. This analysis describes mortality in the KHDSS over 16 years. Methods: We calculated mortality rates from 2003–2018 in four intervals of equal duration and assessed differences in mortality across these intervals by age and sex. We calculated the period survival function and median survival using the Kaplan–Meier method and mean life expectancies using abridged life tables. We estimated trend and seasonality by decomposing a time series of monthly mortality rates. We used choropleth maps and random-effects Poisson regression to investigate geographical heterogeneity. Results: Mortality declined by 36% overall between 2003–2018 and by 59% in children aged <5 years. Most of the decline occurred between 2003 and 2006. Among adults, the greatest decline (49%) was observed in those aged 15–54 years. Life expectancy at birth increased by 12 years. Females outlived males by 6 years. Seasonality was only evident in the 1–4 year age group in the first four years. Geographical variation in mortality was ±10% of the median value and did not change over time. Conclusions: Between 2003 and 2018, mortality among children and young adults has improved substantially. The steep decline in 2003–2006 followed by a much slower reduction thereafter suggests improvements in health and wellbeing have plateaued in the last 12 years. However, there is substantial inequality in mortality experience by geographical location.

Privacy of study participants in open-access Health and Demographic Surveillance System data: A requirements analysis for data anonymisation (Preprint)

BACKGROUND Sharing and anonymising data have become hot topics for individuals, organisations, and countries around the world. Open-access sharing of anonymised data containing sensitive information about individuals makes the most sense whenever the utility of the data can be preserved and the risk of disclosure can be kept below acceptable levels. In this case, researchers can use the data without access restrictions and limitations. OBJECTIVE The goal of this paper is to highlight solutions and requirements for sharing longitudinal health and surveillance event history data in form of open-access data. The challenges lie in the anonymisation of multiple event dates and the time-varying variables. A sequential approach that adds noise to the event dates is proposed. This approach maintains the event order and preserves the average time between events. Additionally, a nosy neighbor distance-based matching approach to estimate the risk is proposed. Regarding dealing with the key variables that change over time such as educational level or occupation, we make two proposals, one based on limiting the intermediate status of a person (e.g. on education), and the other to achieve k-anonymity in subsets of the data. The proposed approaches were applied to the Karonga Health and Demographic Surveillance System (HDSS) core dataset, which contains longitudinal data from 1995 to the end of 2016 and includes 280,381 event records with time-varying, socio-economic variables and demographic information on individuals. The proposed anonymisation strategy lowers the risk of disclosure to acceptable levels thus allowing sharing of the data. METHODS statistical disclosure control, k-anonymity, adding noise, disclosure risk measurement, event history data anonymization, longitudinal data anonymization, data utility by visual comparisons. RESULTS Anonymized version of event history data including longitudinal information on individuals over time with high data utility. CONCLUSIONS The proposed anonymisation of study participants in event history data including static and time-varying status variables, specifically applied to longitudinal health and demographic surveillance system data, led to an anonymized data set with very low disclosure risk and high data utility ready to be shared to the public in form of an open-access data set. Different level of noise for event history dates were evaluated for disclosure risk and data utility. It turned out that high utility had been achieved even with the highest level of noise. Details matters to ensure consistency/credibility. Most important, the sequential noise approach presented in this paper maintains the event order. It has been shown that not even the event order is preserved but also the time between events is well maintained in comparison to the original data. We also proposed an anonymization strategy to handle the information of time-varying status of educational, occupational level of a person, year of death, year of birth, and number of events of a person. We proposed an approach that preserves the data utility well but limit the number of educational and occupational levels of a person. Using distance-based neighborhood matching we simulated an attack under a nosy neighbor situation and by using a worst-case scenario where attackers has full information on the original data. It could be shown that the disclosure risk is very low even by assuming that the attacker’s data base and information is optimal. The HDSS and medical science research communities in LMIC settings will be the primary beneficiaries of the results and methods presented in this science article, but the results will be useful for anyone working on anonymising longitudinal datasets possibly including also time-varying information and event history data for purposes of sharing. In other words, the proposed approaches can be applied to almost any event history data, and, additionally, to event history data including static and/or status variables that changes its entries in time.

Prevalence, Risk Factors and Morbidity Profile of Schistosoma Infection Among Adults in the Taabo Health and Demographic Surveillance System, South-central Côte d’Ivoire

Background: Schistosomiasis remains an important public health issue among adults and infected individuals not treated serve as a reservoir of the parasite. Despite this fact, evidence on the epidemiology of schistosomiasis in adults in Côte d’Ivoire is scanty. This study aimed to determine the prevalence and risk factors of schistosomiasis among adults in the Taabo health and demographic surveillance system in the south-central part of Côte d’Ivoire.Methods: A cross-sectional survey was carried out in April and May 2017 in the frame of the “Côte d’Ivoire Dual Burden of Disease Study” (CoDuBu). A total of 901 randomly selected individuals, aged 18-90 years, provided blood, stool and urine samples for the diagnosis of malaria and helminth infections. With an emphasis on schistosomiasis, stool samples were subjected to the Kato-Katz technique for detection of Schistosoma mansoni eggs, while urine samples were examined for eggs of Schistosoma haematobium and circulating cathodic antigen of S. mansoni. Risk factors and morbidity profiles were assessed using health examination and questionnaires. Multinomial logistic regressions were employed to identify independent risk factors and morbidity patterns associated with S. mansoni mono- and co-infections.Results: The prevalence of S. mansoni and S. haematobium was 23.2% and 1.0%, respectively. Most S. mansoni were mono-infections (81.3%). Independent determinants of S. mansoni infection were young age, low socioeconomic status (mono- and co-infection) and poor hygiene practices (co-infection). S. mansoni infection was independently associated with higher pain and symptom scores (mono-infection), poor self-rated health and low healthcare use (co-infection).Conclusions: This study showed that adults represent a substantial reservoir of S. mansoni. To sustain schistosomiasis control and improve people’s wellbeing, it is important to expand preventive chemotherapy from school-aged children to adults, coupled with hygiene and health education.

Factors related with the incidence of acute respiratory infections in toddlers in Sleman, Yogyakarta, Indonesia: Evidence from the Sleman Health and Demographic Surveillance System

Various factors associated with Acute Respiratory Infections (ARI) in toddlers have been widely observed, but there are no studies using data from the Sleman Health and Demographic Surveillance System (HDSS). This study aimed to determine the factors associated with ARI in children under five in Sleman, Yogyakarta, Indonesia. This research was an observational analytic study with a cross-sectional design, using secondary data from the Sleman HDSS. Data of 463 children under five who met the inclusion and exclusion criteria were used in this study. Inclusion criteria were toddlers who have complete observed variable data. The variables observed were the characteristics of children under five, the attributes of the mother, the physical condition of the house, the use of mosquito coils, sanitation facilities, and sources of drinking water. The exclusion criteria were toddlers with pulmonary tuberculosis in the past year. Data analysis used chi-squared tests for bivariate analysis and multivariate logistic regression analysis. The results showed that working mothers had a greater risk of ARI under five children with OR 1.46 (95% CI = 1.01–2.11), and groundwater as a water source was a protective factor against the occurrence of ARI in toddlers with OR 0.46 (95% CI = 0.26–0.81). After a logistic regression analysis was performed, only the drinking water source variable had a statistically significant relationship with the incidence of ARI in children under five with OR = 0.47 (95% CI = 0.268–0.827). Research on the relationship between water quality and the incidence of ARI in children under five is needed to follow up on these findings.

Mortality in Rural Coastal Kenya measured using the Kilifi Health and Demographic Surveillance System: A 16-year descriptive analysis

Background The Kilifi Health and Demographic Surveillance System (KHDSS) was established in 2000 to define the incidence and prevalence of local diseases and evaluate the impact of community-based interventions. KHDSS morbidity data have been reported comprehensively but mortality has not been described. This analysis describes mortality in the KHDSS over 16 years. Methods We calculated mortality rates from 2003-2018 in four intervals of equal duration and assessed differences in mortality across these intervals by age and sex. We calculated the period survival function and median survival using the Kaplan-Meier method and mean life expectancies using abridged life tables. We estimated trend and seasonality by decomposing a time series of monthly mortality rates. We used choropleth maps and random effects Poisson regression to investigate geographical heterogeneity. Results Mortality declined by 36% overall between 2003-2018 and by 59% in children aged <5 years. Most of the decline occurred between 2003 and 2006. Among adults, the greatest decline (49%) was observed in those aged 15-54 years. Life expectancy at birth increased by 12 years. Females outlived males by 6 years. Seasonality was only evident in the 1-4 year age group in the first four years. Geographical variation in mortality was +/-10% of the median value and did not change over time. Conclusions Between 2003-2018 mortality among children and young adults has improved substantially. The steep decline in 2003-2006 followed by a much slower reduction thereafter suggests improvements in health and wellbeing have plateaued in the last 12 years. However, there is substantial inequality in mortality experience by geographical location.

Persistence of child marriage in rural Bangladesh and impact on maternal and perinatal health: findings from a health and demographic surveillance system

ABSTRACTObjectivesTo describe temporal trends in child marriage between 1990 and 2019 in a rural sub-district of Bangladesh and characterize relationships between age, time to pregnancy, complications during delivery, and perinatal mortality.DesignHealth and demographic surveillance system.SettingBaliakandi sub-district, Bangladesh.Participants56,155 female residents.Main outcome measuresAnnual proportion of marriages to female residents under 18 years of age, time between first marriage and pregnancy, proportion of births with complications during delivery, and odds of perinatal mortality.ResultsBetween 1990 and 2010, the proportion of marriages to female residents under 18 years of age decreased from 71% to 57%. Most notably, marriages to females aged 10 to 12 years dropped from 22% of all marriages to 3%. In 2019, 53% of all marriages were to females under 18 years. The estimated time between first marriage and pregnancy did not differ by female age at marriage. By 365 days after marriage, the cumulative incidence of pregnancy was approximately 50% for each age group. Adolescent girls were more likely to experience complications during delivery with at least one complication reported for 36% of mothers aged 13 to 15 years, 32% of mothers aged 16 to 17 years, and 23% of mothers aged 18 to 34 years (χ2 test, P<0.001). Compared to adults, births among females aged 13 to 15 years were more likely to result in stillbirths (odds ratio 2.23, 95% confidence interval 1.19 to 4.16) and births among females 16-17 years were more likely to result in early neonatal deaths (odds ratio 1.57, 95% confidence interval 1.01 to 2.42).ConclusionsChild marriage persists in Baliakandi. Over half of all marriages were to child brides and only minor reductions were seen over the past decade. Pregnancies were common among adolescent girls with no evidence of delayed pregnancy after marriage. Compared to adults, adolescents were more likely to experience complications during delivery and perinatal death. Preventing child marriage has substantial social and health benefits for girls and, by doing so, will also contribute to Bangladesh’s commitment to reduce child mortality.

Magnitude, trends and determinants of skilled delivery from Kilite-Awlaelo Health Demographic Surveillance System, Northern Ethiopia, 2009- 2017

Background The fundamental approach to improve maternal and neonatal health is increasing skilled delivery rate. Women giving birth at health institutions can prevent maternal and neonatal deaths by getting skilled birth attendance. In Ethiopia, despite a significant decrease in maternal mortality over the past decade, still a significant number of women give birth at home. Moreover, evidence from population-based longitudinal studies on skilled delivery is limited. Therefore, this study aims to investigate the magnitude, trend, and determinants of skilled delivery in Kilite-Awlaelo Health Demographic Surveillance System (KA-HDSS), Northern Ethiopia. Method Population-based longitudinal study design was conducted by extracting data for nine consecutive years (2009–2017) from KA-HDSS database. In order to measure the trends of skilled delivery, KA-HDSS data sets were analyzed (2009–2017). Bivariate and multivariate analyses were performed using STATA version 16. A multivariable binary logistic regression model was fitted to assess determinants of skilled delivery and odds ratio with 95% CI was used to assess presence of associations at a 0.05 level of significance. Results The skilled delivery rate have continuously increased among reproductive age women from 15.12% (95% CI: 13.30% - 17.09%) in 2010 to 95.85% (95% CI: 94.58% - 96.895%) in 2017. The skilled delivery rate becomes high (> = 82) in the period of 2014–2017. Education, residence, marital status, occupation and antenatal care (ANC) visits were the most important determinants for skilled delivery among reproductive age women during the period of high skilled delivery rate (2014–2017). Women urban dwellers had about 28 times (AOR = 27.66; 95% CI: 3.86–196.97) higher odds to deliver by skilled birth attendants than rural dwellers. Unmarried women who gave birth were 2.18 (AOR: 2.18; 95% CI: 1.30–3.64) times more likely to have skilled delivery service compared to those married. Likewise, women with four or more ANC visits were 3.2 times more likely to undergo skilled delivery service than those having no ANC visits (AOR: 3.16; 95% CI: 2.33–4.28). Moreover, women having at least a secondary education were 2 times more likely to have skilled delivery service compared to those women with no formal education (AOR = 2.10, 95% CI: 1.18–3.74). Conclusion Regardless of the importance of health facility delivery, a significant number of women still deliver at home attended by unskilled birth attendants. There has been a substantial increase in use of health facilities for delivery among women in the reproductive age. The factors affecting skilled delivery among reproductive age women were educational level, residence, marital status, occupation and use of ANC service. Maternal health related interventions are needed to change women’s attitudes towards skilled delivery. Moreover, ANC coverage should be increased to improve skilled delivery service.

Vibrio cholerae O139 persists in Dhaka, Bangladesh since 1993

Background After a multi-country Asian outbreak of cholera due to Vibrio cholerae serogroup O139 which started in 1992, it is rarely detected from any country in Asia and has not been detected from patients in Africa. Methodology/Principal findings We extracted surveillance data from the Dhaka and Matlab Hospitals of International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) to review trends in isolation of Vibrio cholerae O139 in Bangladesh. Data from the Dhaka Hospital is a 2% sample of > 100,000 diarrhoeal patients treated annually. Data from the Matlab Hospital includes all diarrhoeal patients who hail from the villages included in the Matlab Health and Demographic Surveillance System. Vibrio cholerae O139 was first isolated in Dhaka in 1993 and had been isolated every year since then except for a gap between 2005 and 2008. An average of thirteen isolates was detected annually from the Dhaka Hospital during the last ten years, yielding an estimated 650 cases annually at this hospital. During the last ten years, cases due to serogroup O139 represented 0.47% of all cholera cases; the others being due to serogroup O1. No cases with serogroup O139 were identified at Matlab since 2006. Clinical signs and symptoms of cholera due to serogroup O139 were similar to cases due to serogroup O1 though more of the O139 cases were not dehydrated. Most isolates of O139 remained sensitive to tetracycline, ciprofloxacin, and azithromycin, but they became resistant to erythromycin starting in 2009. Conclusions/Significance Cholera due to Vibrio cholerae serogroup O139 continues to cause typical cholera in Dhaka, Bangladesh.