Evaluation of acute flaccid paralysis surveillance performance before and during the 2014-2015 Ebola virus disease outbreak in Guinea and Liberia.

Introduction: the number of wild poliomyelitis cases, worldwide, dropped from 350,000 cases in 1988 to 33 in 2018. Acute flaccid paralysis (AFP) surveillance is a key strategy toward achieving global polio eradication. The 2014 Ebola virus disease (EVD) epidemic in West Africa infected over 28,000 people and had devastating effects on health systems in Guinea, Liberia, and Sierra Leone. We sought to assess the effects of the 2014 Ebola outbreak on AFP surveillance in Guinea and Liberia. Methods: a retrospective cross-sectional analysis was performed for Guinea and Liberia to evaluate EVD´s impact on World Health Organization (WHO) AFP surveillance performance indicators during 2012-2015. Results: both Guinea and Liberia met the WHO target non-polio AFP incidence rate nationally, and generally sub-nationally, prior to the EVD outbreak; rates decreased substantially during the outbreak in seven of eight regions in Guinea and 11 of 15 counties in Liberia. Throughout the study period, both Guinea and Liberia attained appropriate overall targets nationally for "notification" and "stool adequacy" indicators, but each country experienced periods of poor regional/county-specific indicator performance. Conclusion: these findings mirrored the negative effect of the Ebola outbreak on polio elimination activities in both countries and highlights the need to reinforce this surveillance system during times of crisis.

Ensemble learning to predict opioid-related overdose using statewide prescription drug monitoring program and hospital discharge data in the state of Tennessee.

OBJECTIVE: To develop and validate algorithms for predicting 30-day fatal and nonfatal opioid-related overdose using statewide data sources including prescription drug monitoring program data, Hospital Discharge Data System data, and Tennessee (TN) vital records. Current overdose prevention efforts in TN rely on descriptive and retrospective analyses without prognostication. MATERIALS AND METHODS: Study data included 3 041 668 TN patients with 71 479 191 controlled substance prescriptions from 2012 to 2017. Statewide data and socioeconomic indicators were used to train, ensemble, and calibrate 10 nonparametric "weak learner" models. Validation was performed using area under the receiver operating curve (AUROC), area under the precision recall curve, risk concentration, and Spiegelhalter z-test statistic. RESULTS: Within 30 days, 2574 fatal overdoses occurred after 4912 prescriptions (0.0069%) and 8455 nonfatal overdoses occurred after 19 460 prescriptions (0.027%). Discrimination and calibration improved after ensembling (AUROC: 0.79-0.83; Spiegelhalter P value: 0-.12). Risk concentration captured 47-52% of cases in the top quantiles of predicted probabilities. DISCUSSION: Partitioning and ensembling enabled all study data to be used given computational limits and helped mediate case imbalance. Predicting risk at the prescription level can aggregate risk to the patient, provider, pharmacy, county, and regional levels. Implementing these models into Tennessee Department of Health systems might enable more granular risk quantification. Prospective validation with more recent data is needed. CONCLUSION: Predicting opioid-related overdose risk at statewide scales remains difficult and models like these, which required a partnership between an academic institution and state health agency to develop, may complement traditional epidemiological methods of risk identification and inform public health decisions.

Geospatial analyses identify regional hot spots of diffuse gastric cancer in rural Central America.

BACKGROUND: Geospatial technology has facilitated the discovery of disease distributions and etiology and helped target prevention programs. Globally, gastric cancer is the leading infection-associated cancer, and third leading cause of cancer mortality worldwide, with marked geographic variation. Central and South America have a significant burden, particularly in the mountainous regions. In the context of an ongoing population-based case-control study in Central America, our aim was to examine the spatial epidemiology of gastric cancer subtypes and H. pylori virulence factors. METHODS: Patients diagnosed with gastric cancer from 2002 to 2013 in western Honduras were identified in the prospective gastric cancer registry at the principal district hospital. Diagnosis was based on endoscopy and confirmatory histopathology. Geospatial methods were applied using the ArcGIS v10.3.1 and SaTScan v9.4.2 platforms to examine regional distributions of the gastric cancer histologic subtypes (Lauren classification), and the H. pylori CagA virulence factor. Getis-Ord-Gi hot spot and Discrete Poisson SaTScan statistics, respectively, were used to explore spatial clustering at the village level (30-50 rural households), with standardization by each village's population. H. pylori and CagA serologic status was determined using the novel H. pylori multiplex assay (DKFZ, Germany). RESULTS: Three hundred seventy-eight incident cases met the inclusion criteria (mean age 63.7, male 66.3%). Areas of higher gastric cancer incidence were identified. Significant spatial clustering of diffuse histology adenocarcinoma was revealed both by the Getis-Ord-GI* hot spot analysis (P-value < 0.0015; range 0.00003-0.0014; 99%CI), and by the SaTScan statistic (P-value < 0.006; range 0.0026-0.0054). The intestinal subtype was randomly distributed. H. pylori CagA had significant spatial clustering only in association with the diffuse histology cancer hot spot (Getis-Ord-Gi* P value ≤0.001; range 0.0001-0.0010; SaTScan statistic P value 0.0085). In the diffuse gastric cancer hot spot, the lowest age quartile range was 21-46 years, significantly lower than the intestinal cancers (P = 0.024). CONCLUSIONS: Geospatial methods have identified a significant cluster of incident diffuse type adenocarcinoma cases in rural Central America, suggest of a germline genetic association. Further genomic and geospatial analyses to identify potential spatial patterns of genetic, bacterial, and environmental risk factors may be informative.

Congenital Malformations of the Central Nervous System in Rural Western Honduras: A 6-Year Report on Trends.

BACKGROUND: Central nervous system (CNS) malformations, including neural tube defects (NTDs), are the second most common type of birth defects worldwide and are major causes of childhood disability and mortality. We report the first analysis of birth prevalence in Western Honduras of CNS malformations including NTDs over 6 consecutive years. METHODS: Data from all patients with congenital CNS malformations and total live births for the period 2010-2015 were obtained through institution and regional registries from all 3 public referral hospitals in Western Honduras, representing 67 municipalities. Cases were identified using the International Classification of Diseases, Tenth Revision CNS malformation codes. Birth prevalence was calculated as cases per 10,000 live births. RESULTS: From 123,903 live births, 275 cases of CNS malformations were identified (54% females, 58% NTDs). Six-year birth prevalence of CNS malformations was 13.9-31.1. Spina bifida variants and anencephaly represented 80% and 19% of reported NTDs, respectively. Total 6-year prevalence of NTDs in Western Honduras was 7.0-17.4 over years studied. In 6 municipalities, average prevalence was >30 (maximum 49.0). CONCLUSION: This is the first study reporting disease burden of CNS malformations in Western Honduras. The nationwide birth prevalence of NTDs in rural Honduras may have decreased since the implementation of prenatal health policies in 2005. However, we identified regions with unexpectedly elevated prevalence, indicating high regional prevalence that could be targeted for improved preventive efforts, ultimately decreasing the burden of these conditions.

Determinants of full vaccination status in children aged 12-23 months in Gurùé and Milange districts, Mozambique: results of a population-based cross-sectional survey.

Background: In 2011, 64% of children in Mozambique, ages 12-23 months, were fully immunized. Large provincial differences in vaccine uptake exist. Methods: We conducted a survey of 1650 females with children aged 12-23 months in the districts of Gurùé and Milange. Implementation occurred from November to December 2014. Descriptive statistics and logistic regression using R-software 3.0.2 were used to examine factors associated with full vaccination status. ArcGIS version 10.3.1 (ESRI, Redlands, CA, USA) was used to map spatial patterns of vaccine uptake. Results: Full vaccination was roughly 48%. Identifying 'hospital' as a location to get vaccinated was associated with having a fully vaccinated child (OR=1.87, 95% CI=1.02, 3.41, p=0.043). Households where health decisions are made solely by the male or the female had 38% (95% CI=0.32, 1.21) and 55% (95% CI=0.29, 0.69) lower odds, respectively, of their child being fully immunized. For every 10 km increase from the nearest health facility there was a 36% lower odds of the child being fully immunized (OR=0.64, 95% CI=0.44, 0.93, p<0.001). Conclusion: Zambézia Province, as a whole and the districts of Gurùé and Milange specifically, is falling short of vaccination targets. Intensified efforts focused on the least educated, most distant and which take a more family-centered approach are needed to improve vaccine uptake.

Spatial analysis of the regional variation of reproductive tract infections and spousal migration correlates in Nepal.

Nepal has a diverse geographic landscape that could potentially create clustered subpopulations with regional socio-cultures that could result in differential health outcomes. With an alarming rise in married male populations migrating for work, it is possible that these migrants are engaged in risky sexual behaviour, putting their wives at risk for infectious disease outcomes, including reproductive tract infections (RTI), when they return home. The prevalence of male migration varies by geographic region in Nepal and this variation could potentially contribute to different RTI rates. Using a cross-sectional dataset (the 2011 Nepal Demographic and Health Survey) including 9607 married women, we investigated geospatial and socio-cultural factors associated with the symptoms of RTIs with a focus on the husbands' migration status. Choropleth maps were created to illustrate areas with high percentages of RTIs that correlated with migration patterns. Overall, 31.9% of the husbands were migrating for work. After adjusting for wealth, contraception use, age at first marriage, urban/rural status and husband's education, women whose husbands had been absent for a year or more in Nepal's Mid-West region (OR 1.93 95%, CI 1.02-3.67) or Far-West region (OR 2.89 95%, CI 1.24-6.73) were more likely to report RTI-like symptoms than others. Our results suggest a potential association between husbands' migration status and Nepali women reporting RTI symptoms by geographic regions. However, further research is needed to put this outcome on a stronger footing with respect to this under-studied population, specifically in the context of geographical variation.

Prevalence and determinants of malaria among children in Zambézia Province, Mozambique.

BACKGROUND: Malaria is the leading cause of death among children in Mozambique. Prevalence and factors associated with malaria are not well studied among children in rural Zambézia Province. Whether prevalence of malaria varies across diverse districts within the province is unknown. METHODS: A cross-sectional survey of female heads of household was conducted during April and May 2014, a period of peak malaria transmission. Data were collected on up to two randomly selected children aged 6-59 months per household. The outcome of interest was self-report of symptomatic malaria confirmed by diagnostic test in the past 30 days. Analyses accounted for the two-stage cluster sample design. Prevalence of symptomatic malaria was calculated for the province and three over-sampled focus districts-Alto Molócuè, Morrumbala, and Namacurra. Multivariable logistic regression of symptomatic malaria diagnosis included: district, age, sex, education, bed net use, urban setting, distance to health facility, income, roofing material, and pig farming. RESULTS: Data were collected on 2540 children. Fifty percent were female, and the median age was 24 months. Sixty percent of children slept under bed nets the night prior to the survey, but utilization varied between districts (range 49-89%; p < 0.001). Forty-three percent of children reported fever in the past 30 days, 91% of those sought care at a health facility, 67% of those had either a malaria rapid diagnostic test or blood smear, and 67% of those had a positive test result and therefore met our case definition of self-reported symptomatic malaria. There were significant differences in prevalence of fever (p < 0.001), health-seeking (p < 0.001), and diagnostic testing (p = 0.003) between focus districts. Province-wide prevalence of symptomatic malaria was 13% and among focus districts ranged from 14% in Morrumbala to 17% in Namacurra (p < 0.001). Higher female caregiver education (OR 1.88; 95% CI 1.31-2.70), having fewer young children in the household (OR 1.25; 95% CI 1.01-1.56), and higher income (OR 1.56; 95% CI 1.11-2.22) were independently associated with having a child with symptomatic malaria. CONCLUSIONS: Self-reported symptomatic malaria is highly prevalent among children in Zambézia Province, Mozambique and varies significantly between diverse districts. Factors facilitating access to health services are associated with symptomatic malaria diagnosis. These findings should inform resource allocation in the fight against malaria in Mozambique.

Understanding intra-vaginal and labia minora elongation practices among women heads-of-households in Zambézia Province, Mozambique.

Intra-vaginal drying and tightening and labia minora elongation are commonly practised in some parts of southern Africa. We sought to capture data on these practices among women living in Zambézia province, Mozambique. Information was gathered from 3543 female heads of household on > 500 variables, including vaginal practices, in 2014. Women who planned to use intra-vaginal tightening substances had 1.84 times higher odds of ever receiving an HIV test (p < 0.001) and 1.40 times higher odds of at least one antenatal care visit attended during last pregnancy (p = 0.015). Women who had or planned to undergo labia minora elongation had 2.61 times higher odds of receiving an HIV test in the past (p < 0.001) and 1.60 times higher odds of attending at least one antenatal care visit during their last pregnancy (p < 0.001). There was little evidence for a relationship between self-reported HIV status and anticipated use of intra-vaginal tightening substances (p = 0.21). Current or anticipated participation in labia elongation showed a protective effect on HIV infection (p = 0.028). Given documented associations between intra-vaginal substance use, vaginal infections and HIV acquisition, understanding the prevalence of vaginal practices is an essential component to addressing the epidemic.

Prevalence and determinants of malaria among children in Zambézia Province, Mozambique

Background: Malaria is the leading cause of death among children in Mozambique. Prevalence and factors associated with malaria are not well studied among children in rural Zambézia Province. Whether prevalence of malaria varies across diverse districts within the province is unknown. Methods: A cross­sectional survey of female heads of household was conducted during April and May 2014, a period of peak malaria transmission. Data were collected on up to two randomly selected children aged 6­59 months per household. The outcome of interest was self­report of symptomatic malaria confirmed by diagnostic test in the past 30 days. Analyses accounted for the two­stage cluster sample design. Prevalence of symptomatic malaria was calculated for the province and three over­sampled focus districts­Alto Molócuè, Morrumbala, and Namacurra. Multivariable logistic regression of symptomatic malaria diagnosis included: district, age, sex, education, bed net use, urban setting, distance to health facility, income, roofing material, and pig farming. Results: Data were collected on 2540 children. Fifty percent were female, and the median age was 24 months. Sixty percent of children slept under bed nets the night prior to the survey, but utilization varied between districts (range 49­89%; p < 0.001). Forty­three percent of children reported fever in the past 30 days, 91% of those sought care at a health facility, 67% of those had either a malaria rapid diagnostic test or blood smear, and 67% of those had a positive test result and therefore met our case definition of self­reported symptomatic malaria. There were significant differences in prevalence of fever (p < 0.001), health­seeking (p < 0.001), and diagnostic testing (p = 0.003) between focus districts. Province­wide prevalence of symptomatic malaria was 13% and among focus districts ranged from 14% in Morrumbala to 17% in Namacurra (p < 0.001). Higher female caregiver education (OR 1.88; 95% CI 1.31­2.70), having fewer young children in the household (OR 1.25; 95% CI 1.01­1.56), and higher income (OR 1.56; 95% CI 1.11­2.22) were independently associated with having a child with symptomatic malaria. Conclusions: Self­reported symptomatic malaria is highly prevalent among children in Zambézia Province, Mozambique and varies significantly between diverse districts. Factors facilitating access to health services are associated with symptomatic malaria diagnosis. These findings should inform resource allocation in the fight against malaria in Mozambique.

Spatial and Temporal Spread of Acute Viral Respiratory Infections in Young Children Living in High-altitude Rural Communities: A Prospective Household-based Study.

BACKGROUND: Few studies have described patterns of transmission of viral acute respiratory infections (ARI) in children in developing countries. We examined the spatial and temporal spread of viral ARI among young children in rural Peruvian highland communities. Previous studies have described intense social interactions in those communities, which could influence the transmission of viral infections. METHODS: We enrolled and followed children <3 years of age for detection of ARI during the 2009 to 2011 respiratory seasons in a rural setting with relatively wide geographic dispersion of households and communities. Viruses detected included influenza, respiratory syncytial virus (RSV), human metapneumovirus and parainfluenza 2 and 3 viruses (PIV2, PIV3). We used geospatial analyses to identify specific viral infection hot spots with high ARI incidence. We also explored the local spread of ARI from index cases using standard deviational ellipses. RESULTS: Geospatial analyses revealed hot spots of high ARI incidence around the index cases of influenza outbreaks and RSV outbreak in 2010. Although PIV3 in 2009 and PIV2 in 2010 showed distinct spatial hot spots, clustering was not in proximity to their respective index cases. No significant aggregation around index cases was noted for other viruses. Standard deviational ellipse analyses suggested that influenza B and RSV in 2010, and human metapneumovirus in 2011 spread temporally in alignment with the major road network. CONCLUSIONS: Despite the geographic dispersion of communities in this rural setting, we observed a rapid spread of viral ARI among young children. Influenza strains and RSV in 2010 had distinctive outbreaks arising from their index cases.