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.

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.

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.