The downstream effects of COVID-19 on adolescent girls in the Peruvian Amazon: qualitative findings on how the pandemic affected education and reproductive health

Due to COVID-19, schools were closed to mitigate disease spread. Past studies have shown that disruptions in education have unintended consequences for adolescents, including increasing their risk of school dropout, exploitation, gender-based violence, pregnancy and early unions. In Peru, the government closed schools from March 2020 to March 2022, declaring a national emergency that affected an estimated 8 million children. These closures may have unintended consequences, including increased adolescent pregnancy, particularly in Peru's rural, largely indigenous regions. Loreto, located in the Peruvian Amazon, has one of the highest adolescent pregnancy rates in the country and poor maternal and child health outcomes. The underlying causes may not be fully understood as data are limited, especially as we transition out of the pandemic. This qualitative study investigated the downstream effects of COVID-19 on adolescent education and reproductive health in Loreto's districts of Nauta and Parinari. In-depth interviews (n=41) were conducted with adolescents and community leaders. These were held in June 2022, 3 months after the reinstitution of in-person classes throughout Peru. Focus group discussions (FGDs) were also completed with community health workers and educators from the same study area in October 2022 to supplement our findings (3 FGDs, n=15). We observed that the economic, educational and health effects of the COVID-19 pandemic contributed to reduced contraceptive use, and increased school abandonment, early unions and adolescent pregnancy. The interplay between adolescent pregnancy and both early unions and school abandonment was bidirectional, with each acting as both a cause and consequence of the other.

Exploring the association of weather variability on Campylobacter - A systematic review

BACKGROUND

Previous work has found climate change-induced weather variability is suspected to increase the transmission of enteric pathogens, including Campylobacter, a leading cause of bacterial gastroenteritis. While the relationship between extreme weather events and diarrheal diseases has been documented, the specific impact on Campylobacter infections remains underexplored.

OBJECTIVE

To synthesize the peer-reviewed literature exploring the effect of weather variability on Campylobacter infections in humans.

METHODS

The review included English language, peer-reviewed articles, published up to September 1, 2022 in PubMed, Embase, GEOBASE, Agriculture and Environmental Science Database, and CABI Global Health exploring the effect of an antecedent weather event on human enteric illness caused by Campylobacter (PROSPERO Protocol # 351884). We extracted study information including data sources, methods, summary measures, and effect sizes. Quality and weight of evidence reported was summarized and bias assessed for each article.

RESULTS

After screening 278 articles, 47 articles (34 studies, 13 outbreak reports) were included in the evidence synthesis. Antecedent weather events included precipitation (n = 35), temperature (n = 30), relative humidity (n = 7), sunshine (n = 6), and El Niño and La Niña (n = 3). Reviewed studies demonstrated that increases in precipitation and temperature were correlated with Campylobacter infections under specific conditions, whereas low relative humidity and sunshine were negatively correlated. Articles estimating the effect of animal operations (n = 15) found presence and density of animal operations were significantly associated with infections. However, most of the included articles did not assess confounding by seasonality, presence of animal operations, or describe estimates of risk.

DISCUSSION

This review explores what is known about the influence of weather events on Campylobacter and identifies previously underreported negative associations between low relative humidity and sunshine on Campylobacter infections. Future research should explore pathogen-specific estimates of risk, which can be used to influence public health strategies, improve source attribution and causal pathways, and project disease burden due to climate change.

'You have a lot of mirrors': structural and socioecological factors impacting adolescent pregnancy and reproductive health in the Amazon basin, Peru, a qualitative study

Loreto, in the Peruvian Amazon, has one of the highest adolescent pregnancy rates in the country. However, underlying causes of adolescent pregnancy are not fully understood as data are limited in Indigenous and remote Amazonian communities. This study investigated adolescent reproductive health within Loreto using an ecological systems framework. Forty-one semi-structured interviews were conducted in June 2022: community leaders (n = 12) and adolescent participants between 15 and 17 years of age (pregnant girls, n = 11; never pregnant girls, n = 9; and boys, n = 9). We also conducted focus group discussions with community health workers and educators in October 2022 (three focus groups, n = 15). Adolescent reproductive health is complex with multi-layered factors that put girls at higher risk of pregnancy. We found a paradoxical relationship between expected social and gender norms and individual desires. This research provides a contextual understanding of the lived experience of adolescents and young people in the Amazon region of Peru. Our findings suggest the need for greater exploration of the contradictory ideas surrounding adolescent pregnancy and female sexuality.

Antibiotic Resistance Rates for Helicobacter pylori in Rural Arizona: A Molecular-Based Study

Helicobacter pylori (H. pylori) is a common bacterial infection linked to gastric malignancies. While H. pylori infection and gastric cancer rates are decreasing, antibiotic resistance varies greatly by community. Little is known about resistance rates among rural Indigenous populations in the United States. From 2018 to 2021, 396 endoscopy patients were recruited from a Northern Arizona clinic, where community H. pylori prevalence is near 60%. Gastric biopsy samples positive for H. pylori (n = 67) were sequenced for clarithromycin- and metronidazole-associated mutations, 23S ribosomal RNA (23S), and oxygen-insensitive NADPH nitroreductase (rdxA) regions. Medical record data were extracted for endoscopic findings and prior H. pylori history. Data analysis was restricted to individuals with no history of H. pylori infection. Of 49 individuals, representing 64 samples which amplified in the 23S region, a clarithromycin-associated mutation was present in 38.8%, with T2182C being the most common mutation at 90%. While the prevalence of metronidazole-resistance-associated mutations was higher at 93.9%, the mutations were more variable, with D95N being the most common followed by L62V. No statistically significant sex differences were observed for either antibiotic. Given the risk of treatment failure with antibiotic resistance, there is a need to consider resistance profile during treatment selection. The resistance rates in this population of American Indian patients undergoing endoscopy are similar to other high-risk populations. This is concerning given the high H. pylori prevalence and low rates of resistance testing in clinical settings. The mutations reported are associated with antibiotic resistance, but clinical resistance must be confirmed.

Helicobacter pylori treatment knowledge, access and barriers: A cross-sectional study

BACKGROUND

Helicobacter pylori (Hp) is among the most common bacterial infections in the world and one of the most common infectious agents linked to malignancy, gastric cancer (GC). Within the US there is high disparity in the rates of Hp infection and associated diseases. Hp infection is treatable, and knowledge may influence screening and treatment seeking behaviors.

MATERIALS AND METHODS

In this cross-sectional study of 1042 respondents recruited from the Online Amazon MTurk platform, we sought to assess baseline knowledge of Hp and to gain insight into barriers related to Hp care.

RESULTS

Just over half (52.3%) reported some prior knowledge of Hp with 11.7% (n = 122) reporting being treated for Hp themselves and 21.4% reporting family members diagnosed with Hp. Of respondents reporting prior treatment, 95 (78%) reported GI upset and 27 (21%) reported not completing medications. Specific to Hp and GC, 70% indicated that a belief that the treatment was worse than the symptoms would affect their willingness to seek care, while 81% indicated knowing Hp can cause GC would affect their treatment decisions and knowing their gastric symptoms were caused by Hp would affect their willingness to receive care.

CONCLUSIONS

Knowledge of Hp in this US sample of online respondents is low and self-reported difficulties with treatment compliance is high. Increasing awareness of this infection and addressing the challenges to treatment compliance could potentially reduce rates of Hp antibiotic resistance and progression to GC or other complications of Hp infection.

Comparison of Prognostic Factors for Merkel Cell Carcinoma, Mucosal Melanoma and Cutaneous Malignant Melanoma: Insights into Their Etiologies

Little is known about the epidemiology of Merkel cell carcinoma (MCC) and mucosal melanoma (MM). Using the United States (US) National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) program data, we compared MCC and MM with cutaneous malignant melanoma (CMM) with respect to incidence rates and prognostic factors to better understand disease etiologies. We describe the proportional incidences of the three cancers along with their survival rates based on 20 years of national data. The incidence rates in 2000–2019 were 203.7 per 1,000,000 people for CMM, 5.9 per 1,000,000 people for MCC and 0.1 per 1,000,000 people for MM. The rates of these cancers increased over time, with the rate of MM tripling between 2000–2009 and 2010–2019. The incidences of these cancers increased with age and rates were highest among non-Hispanic Whites. Fewer MCCs and MMS were diagnosed at the local stage compared with CMM. The cases in the 22 SEER registries in California were not proportional to the 2020 population census but instead were higher than expected for CMM and MCC and lower than expected for MM. Conversely, MM rates were higher than expected in Texas and New York. These analyses highlight similarities in the incidence rates of CMM and MCC—and differences between them and MM rates—by state. Understanding more about MCC and MM is important because of their higher potential for late diagnosis and metastasis, which lead to poor survival.

Estimating Aedes aegypti (Diptera: Culicidae) Flight Distance: Meta-Data Analysis

The yellow fever mosquito, Aedes aegypti, is a growing global concern. An ecological parameter necessary for vector control is the dispersal, or flight range, of mosquito vectors. Information on mosquito dispersal supports identifying optimal sampling and control strategies to limit the invasion of adult mosquitoes. Attempts around the world to understand the movement and flight range of Ae. aegypti have used a variety of techniques, but there has been little agreement regarding flight distances of Ae. aegypti, specifically the average linear distance Ae. aegypti travel in their natural environment. To generate a more robust estimate of Ae. aegypti flight distance, we conducted a meta-data analysis with the aims 1) to provide a flight distance measurement and 2) investigate how mosquito flight range can be affected by study design and climatic factors. Published studies were retrieved from public databases and reviewed for mean distance traveled (MDT) or maximum distance traveled measurements of Ae. aegypti. Linear regression was used to assess potential relationships between Ae. aegypti flight distance and factors pertaining to climate, degrees of urbanization, and study design. MDT estimates were pooled from 27 experiments to calculate a weighted MDT of 105.69 m. This study addresses the average flight distance of Ae. aegypti with the intention of informing vector control programs in Ae. aegypti prevalent regions of the world.

Greening Up For Mosquitoes: A Comparison of Green Stormwater Infrastructure in a Semiarid Region

Green stormwater infrastructure provides environmental, economic, and health benefits as a strategy for building resilience against climate change impacts. However, it may inadvertently increase vulnerability due to improper design and construction or lack of maintenance. We engaged city stakeholders and a diverse student group to investigate possible maladaptation. After rain events, student interns collected data at green stormwater infrastructure, identified in partnership with city stakeholders, for both water retention and mosquito larvae, if present. During the sampling period in 2018, 24 rain events occurred, with 28 sites visited 212 times including visits to basins (63%), curb cuts (34%), and a bioswale (2%). The largest basin consistently retained water (mean: 3.3 days, SD: 2.3 days) and was a positive site for Culex quinquefasciatus, a West Nile virus vector. We found that while basins can become mosquito breeding habitat, there was no evidence that curb cuts were collecting and retaining water long enough. As cities turn to green stormwater infrastructure to address climate change impacts of increasing drought, flooding, and extreme heat, these findings can help in the selection of appropriate infrastructure design typologies.

Evaluating the Strength of Association of Human Papillomavirus Infection With Penile Carcinoma: A Meta-Analysis

BACKGROUND

Human papillomavirus (HPV) is a common sexually transmitted infection that is strongly associated with cervical cancer. A link to penile cancers has been suggested by case series. We sought to assess the strength of the association between HPV infection and penile cancer by meta-analysis.

METHODS

A literature search to identify population-based studies evaluating the risk of HPV infection with penile cancer was conducted via PubMed and Google Scholar databases through December 2020. Studies were included in the pooled analyses if they presented relative risk (RR) estimates comparing penile cancer cases with noncases by HPV exposure status. They were stratified by (1) type of HPV, (2) test used to determine past HPV infection, and (3) the penile cancer type. Pooled analyses were conducted for stratum with at least 2 independent studies using fixed-effects and random-effects models.

RESULTS

Fourteen articles representing 9 study populations fit the inclusion criteria and were included in the pooled analysis. Based on these studies, the pooled RRs are 2.9 (95% confidence interval [CI], 1.7-5.0; n = 4 studies) for invasive penile cancer and seropositivity to HPV16 L1, 4.5 (95% CI, 1.3-15.5; n = 2) for seropositivity to HPV18, and 8.7 for anogenital warts (95% CI, 5.1-14.8; n = 5). For the 3 studies reporting invasive and in situ penile cancer, the risk was 7.6 for anogenital warts.

CONCLUSIONS

The pooled RRs indicate up to a 4.5-fold increased risk between seropositivity for HPV infection and invasive penile cancer. This is much lower than associations seen between HPV and cervical cancer.

Ambient UVR and Environmental Arsenic Exposure in Relation to Cutaneous Melanoma in Iowa

Intermittent sun exposure is the major environmental risk factor for cutaneous melanoma (CM). Cumulative sun exposure and other environmental agents, such as environmental arsenic exposure, have not shown consistent associations. Ambient ultraviolet radiation (UVR) was used to measure individual total sun exposure as this is thought to be less prone to misclassification and recall bias. Data were analyzed from 1096 CM cases and 1033 controls in the Iowa Study of Skin Cancer and Its Causes, a population-based, case-control study. Self-reported residential histories were linked to satellite-derived ambient UVR, spatially derived environmental soil arsenic concentration, and drinking water arsenic concentrations. In men and women, ambient UVR during childhood and adolescence was not associated with CM but was positively associated during adulthood. Lifetime ambient UVR was positively associated with CM in men (OR for highest vs. lowest quartile: 6.09, 95% confidence interval (CI) 2.21–16.8), but this association was not as strong among women (OR for highest vs. lowest quartile: 2.15, 95% CI 0.84–5.54). No association was detected for environmental soil or drinking water arsenic concentrations and CM. Our findings suggest that lifetime and adulthood sun exposures may be important risk factors for CM.

Helicobacter pylori Prevalence and Risk Factors in Three Rural Indigenous Communities of Northern Arizona

Helicobacter pylori (H. pylori) is one of the most common bacterial stomach infections and is implicated in a majority of non-cardia gastric cancer. While gastric cancer has decreased in the United States (US), the incidence in the Navajo Nation is nearly four times higher than surrounding Non-Hispanic White populations. Little is known about H. pylori prevalence in this population or other Indigenous communities in the lower 48 states. In this cross-sectional study, 101 adults representing 73 households from three Navajo Nation chapter communities completed surveys and a urea breath test for active H. pylori. Accounting for intrahousehold correlation, H. pylori prevalence was 56.4% (95% CI, 45.4–66.8) and 72% of households had at least one infected person. The odds of having an active infection in households using unregulated water were 8.85 (95% CI, 1.50–53.38) that of the use of regulated water, and males had 3.26 (95% CI, 1.05–10.07) higher odds than female. The prevalence of H. pylori in Navajo is similar to that seen in Alaska Natives. Further investigation into factors associated with prevention of infection is needed as well as understanding barriers to screening and treatment.

Chagas Disease in Pregnant Women from Endemic Regions Attending the Hospital General de Mexico, Mexico City

Trypanosoma cruzi infection leads to Chagas disease (CD), a neglected tropical infection of significant public health importance in South and Central America and other, non-endemic, countries. Pregnant women and their children are of particular importance to screen as T. cruzi can be transmitted vertically. The objective of this study was to screen for T. cruzi infection among pregnant women from endemic areas seen at the Hospital General de Mexico for prenatal care, so that they and their children may be quickly connected to CD treatment. Pregnant women were recruited through the hospital prenatal clinic and screened for T. cruzi infection using a series of serological and molecular tests. Of 150 screened patients, mean age 26.8 (SD 6.4), 30 (20.0%) were positive by at least one diagnostic test. Of these, only nine (6%) were positive as determined by PCR. Diagnosis of chronic CD is difficult in endemic places like Mexico due to the limitations of current commercially available diagnostic tests. Further evaluation of diagnostic performance of various assays could improve current CD diagnostic algorithms and proper care management in these regions. Genetic variability in the parasite may also play a role in the differing assay performances seen in this study, and this may be a valuable avenue of further research.

COVID-19 prevention measures reduce dengue spread in Yunnan Province, China, but do not reduce established outbreak

The COVID-19 pandemic and measures against it provided a unique opportunity to understand the transmission of other infectious diseases and to evaluate the efficacy of COVID-19 prevention measures on them. Here we show a dengue epidemic in Yunnan, China, during the pandemic of COVID-19 was dramatically reduced compared to non-pandemic years and, importantly, spread was confined to only one city, Ruili. Three key features characterized this dengue outbreak: (i) the urban-to-suburban spread was efficiently blocked; (ii) the scale of epidemic in urban region was less affected; (iii) co-circulation of multiple strains was attenuated. These results suggested that countermeasures taken during COVID-19 pandemic are efficient to prevent dengue transmission between cities and from urban to suburban, as well to reduce the co-circulation of multiple serotypes or genotypes. Nevertheless, as revealed by the spatial analysis, once the dengue outbreak was established, its distribution was very stable and resistant to measures against COVID-19, implying the possibility to develop a precise prediction method.

Flexibility and partnerships perceived as supportive of dual hazard response: COVID-19 and heat related illness, Summer 2020

OBJECTIVES

To understand how health departments implemented the response to the dual hazards of Heat Related Illness (HRI) and COVID-19 in Summer 2020.

METHODS

We interviewed five health jurisdictions with a Building Resilience Against Climate Effects (BRACE) Framework HRI project to understand impacts to organizational roles and preparedness activities, capacity to respond to the heat season, challenges experienced with resources and personnel, and how partners influenced their capacity to respond to dual hazards.

RESULTS

Health jurisdictions working in both heat preparedness and on the COVID-19 response highlighted three components as integral to maintaining public health capacity throughout the pandemic: 1) adapting to changing roles and responsibilities, 2) building and strengthening inter-organizational partnerships, and 3) maintaining flexibility through cross-training as themes to maintain the public health capacity throughout the pandemic.

CONCLUSIONS

With impacts of the changing climate, including resultant extreme events with subsequent public health impacts, simultaneous responses are likely to arise again in the future. Developing cross-training programs, fostering flexibility and adaptability within the workforce, and building and sustaining external partnerships can support health departments anticipating the need to respond to simultaneous public health hazards in the future.

Understanding Mosquito Surveillance Data for Analytic Efforts: A Case Study

Mosquito surveillance data can be used for predicting mosquito distribution and dynamics as they relate to human disease. Often these data are collected by independent agencies and aggregated to state and national level portals to characterize broad spatial and temporal dynamics. These larger repositories may also share the data for use in mosquito and/or disease prediction and forecasting models. Assumed, but not always confirmed, is consistency of data across agencies. Subtle differences in reporting may be important for development and the eventual interpretation of predictive models. Using mosquito vector surveillance data from Arizona as a case study, we found differences among agencies in how trapping practices were reported. Inconsistencies in reporting may interfere with quantitative comparisons if the user has only cursory familiarity with mosquito surveillance data. Some inconsistencies can be overcome if they are explicit in the metadata while others may yield biased estimates if they are not changed in how data are recorded. Sharing of metadata and collaboration between modelers and vector control agencies is necessary for improving the quality of the estimations. Efforts to improve sharing, displaying, and comparing vector data from multiple agencies are underway, but existing data must be used with caution.

Community transmission of multidrug-resistant tuberculosis is associated with activity space overlap in Lima, Peru

Background

Transmission of multidrug-resistant tuberculosis (MDRTB) requires spatial proximity between infectious cases and susceptible persons. We assess activity space overlap among MDRTB cases and community controls to identify potential areas of transmission.

Methods

We enrolled 35 MDRTB cases and 64 TB-free community controls in Lima, Peru. Cases were whole genome sequenced and strain clustering was used as a proxy for transmission. GPS data were gathered from participants over seven days. Kernel density estimation methods were used to construct activity spaces from GPS locations and the utilization distribution overlap index (UDOI) was used to quantify activity space overlap.

Results

Activity spaces of controls (median = 35.6 km², IQR = 25.1–54) were larger than cases (median = 21.3 km², IQR = 17.9–48.6) (P = 0.02). Activity space overlap was greatest among genetically clustered cases (mean UDOI = 0.63, sd = 0.67) and lowest between cases and controls (mean UDOI = 0.13, sd = 0.28). UDOI was positively associated with genetic similarity of MDRTB strains between case pairs (P < 0.001). The odds of two cases being genetically clustered increased by 22% per 0.10 increase in UDOI (OR = 1.22, CI = 1.09–1.36, P < 0.001).

Conclusions

Activity space overlap is associated with MDRTB clustering. MDRTB transmission may be occurring in small, overlapping activity spaces in community settings. GPS studies may be useful in identifying new areas of MDRTB transmission.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-05953-8.

Improving Undergraduate Epidemiology Education: An Example Using Instructional Teams

Epidemiology is a core component of the undergraduate public health curriculum and a critical component of a healthy community and a comprehensive education. Evidence-based, collaborative instructional practices improve student success, reach diverse student populations, and improve learning outcomes. Here we describe the pedagogical approach of an instructional team with which we observed an 18% greater learning gain (95% confidence interval: 6.5, 29.5; t = -3.08; P = 0.002), based on pre-/posttesting in a large (approximately 120 students) undergraduate course, than with the prior course offering. There were no differences in DEW rates (defined as receiving a grade of D (scoring 60%-69%) or E (scoring <60%) or withdrawing (W)) between the 2 offerings, but the ratio of "A" to "B" grades was higher (by approximately 10%) after deployment of the instructional team (Pearson's χ2 (1 degree of freedom) = 4.17, P = 0.041). In addition, students reported greater satisfaction with the course deploying an instructional team (80.4% positive sentiment in course evaluation comments compared with 76.1% in the prior offering). As students and faculty become more familiar with effective evidence-based instructional practices, improvements in student learning can be achieved and the goal of creating an educated citizenry ready to build a healthy society will be more attainable.

Predicting eastern equine encephalitis spread in North America: An ecological study

Eastern equine encephalitis (EEE) is a rare but lethal mosquito-borne zoonotic disease. Recent years have seen incursion into new areas of the USA, and in 2019 the highest number of human cases in decades. Due to the low detection rate of EEE, previous studies were unable to quantify large-scale and recent EEE ecological dynamics. We used Bayesian spatial generalized-linear mixed model to quantify the spatiotemporal dynamics of human EEE incidence in the northeastern USA. In addition, we assessed whether equine EEE incidence has predictive power for human cases, independently from other environmental variables. The predictors of the model were selected based on variable importance. Human incidence increased with temperature seasonality, but decreased with summer temperature, summer, fall, and winter precipitation. We also found EEE transmission in equines strongly associated with human infection (OR: 1.57; 95% CI: 1.52–1.60) and latitudes above 41.9°N after 2018. The study designed for sparse dataset described new and known relationships between human and animal EEE and environmental factors, including geographical directionality. Future models must include equine cases as a risk factor when predicting human EEE risks. Future work is still necessary to ascertain the establishment of EEE in northern latitudes and the robustness of the available data.

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We collected EEE infections in humans and equines in the northeastern USA (2006–2019), at the county level.

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We used reliably interpolated weather data from The PRISM Climate Group.

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The first use of horse cases to predict human cases, controlling for weather and spatial effect.

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Human risk was correlated with equine infection rates, year, latitude, temperature, and precipitation.

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Cases increased in 2019 and above 41.9 degrees latitude, more studies are needed to confirm a northward shift.

Abstract PO-162: Helicobacter pylori in Native Americans in Northern Arizona

Background. Helicobacter pylori, one of the most common bacterial infections worldwide. Chronic infections are associated with gastritis, peptic ulcer, and gastric cancer. While H. pylori infections and gastric cancer are going down in the US, certain populations continue to experience high H. pylori prevalence of infection and a significant burden from stomach cancer. For example, in Arizona H. pylori prevalence of infection among the Navajo is 60% and gastric cancer is 3-4 times higher that of the white population. Objective: The aim of this work was to survey the presence of virulence factors (cagA and vacA) in H. pylori in the Navajo reservation and their association with gastric disease. Methods: The presence of the virulence genes, cagA and vacA in H. pylori was investigated in gastric biopsies from 97 patients attending the gastroenterology clinic in Winslow, AZ. Biopsies were collected from the antrum and fundus and used for histological examination and for molecular characterization. Molecular characterization was performed by looking at type and number of EPIYA motifs in cagA and presence of different alleles in the signal (s) and medium (m) regions of the vacA gene. Results: The infection rate in the biopsy samples was 22.9%. The cagA gene amplified in 76.9% of the cases and analysis of the 3′ region of cagA showed the predominant presence of the “Western CagA” type with the EPIYA-ABC motif (70.0%) the most prevalent. The vacA allele s1bm1 was the most prevalent (76.9%) followed by s2m2 (11.5%). CagA negative isolates were associated with gastritis or normal findings while EPIYA motifs ABCC were present in severe gastric disease. vacA s2m2 were associated with normal findings. Conclusions: In this population, we have found H. pylori genotypes with predominant cagA Western-type and ABC EPIYA motifs. The vacA s1m1 genotype was the most prevalent and seemed to be associated with gastritis. American Indian/Native American populations are at higher risk for gastric cancer than the general US population. It is important to better establish and quantify genotypes of H. pylori to identify bacterial factors involved in the high prevalence of H. pylori and associated disease among the Navajo population.

Citation Format: Fernando P. Monroy, Heidi E. Brown, Priscilla Sanderson, Gregory Jarrin, Mimi Mbegbu, Shari Kyman, Camenlita Chief, Robin B. Harris. Helicobacter pylori in Native Americans in Northern Arizona [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-162.

A 70% Reduction in Mosquito Populations Does Not Require Removal of 70% of Mosquitoes

We added a vector control component to our existing abundance model to simulate intensive vector control in Puerto Rico. Removing 20-30% of gravid females in the model matches observed 60-80% reductions. The model's capacity to reproduce vector control increases its utility for planning and evaluation strategies.

Regional Variation of Pancreatic Cancer Incidence in the Nile Delta Region of Egypt over a Twelve-Year Period

BACKGROUND

Pancreatic cancer is one of the deadliest forms of cancer, with incidence rates rising in many countries around the world. Geographic variation in pancreatic cancer incidence has not been studied extensively, especially in low- and middle-income countries. The aim of this study was to characterize the distribution of pancreatic cancer incidence in the central Nile Delta region of Egypt and to examine differences by urban and rural patient residence using the nation's only population-based cancer registry.

METHODS

Utilizing the Gharbiah province population-based cancer registry, data were abstracted for 1,089 pancreatic cancer cases diagnosed over twelve years from 1999 to 2010. Age- and sex-specific incidence rates were calculated and compared for urban and rural areas of the eight districts of Gharbiah.

RESULTS

Age-adjusted incidence of pancreatic cancer within Gharbiah varied considerably by urban/rural patient residence and by district. Incidence rates were 1.3 times higher in urban compared to rural areas (4.45 per 100,000 in urban areas and 3.43 per 100,000 in rural areas). The highest incidence rates were observed in urban centers of Kotour, El Santa, and Kafr El-Zayat districts (12.94, 8.32, and 7.89, respectively).

CONCLUSION

Incidence rates varied greatly by urban and rural areas and by district of residence in the Nile Delta region of Egypt. Future studies should examine potential environmental risk factors that may contribute to the geographic distribution of pancreatic cancer in this region.

Emerging Evidence for Infectious Causes of Cancer in the United States

Worldwide, infectious agents currently contribute to an estimated 15% of new cancer cases. Most of these (92%, or 2 million new cancer cases) are attributable to 4 infectious agents: Helicobacter pylori, human papillomavirus, and hepatitis B and C viruses. A better understanding of how infectious agents relate to the US cancer burden may assist new diagnostic and treatment efforts. We review US-specific crude mortality rates from infection-associated cancers and describe temporal and spatial trends since 1999. We review the US-specific evidence for infection-cancer associations by reporting available estimates for attributable fractions for the infection-cancer associations. Death due to cancers with established infectious associations varies geographically, but estimates for the US attributable fraction are limited to a few observational studies. To describe the burden of infection-associated cancer in the United States, additional observational studies are necessary to estimate the prevalence of infection nationally and within subpopulations. As infectious associations emerge to explain cancer etiologies, new opportunities and challenges to reducing the burden arise. Improved estimates for the United States would help target interventions to higher-risk subpopulations.

Geospatial characteristics of non-motor vehicle and assault-related trauma events in greater Phoenix, Arizona

BACKGROUND

Injury-causing events are not randomly distributed across a landscape, but how they are associated with the features and characteristics of the places where they occur in Arizona (AZ) remains understudied. Clustering of trauma events and associations with areal sociodemographic characteristics in the greater Phoenix (PHX), AZ region can promote understanding and inform efforts to ameliorate a leading cause of death and disability for Arizonans. The outcomes of interest are trauma events unrelated to motor vehicle crashes (MVC) and the subgroup of trauma events due to interpersonal assaults.

METHODS

A retrospective, ecological study was performed incorporating data from state and national sources for the years 2013-2017. Geographically weighted regression models explored associations between the rates of non-MVC trauma events (n/10,000 population) and the subgroup of assaultive trauma events per 1000 and areal characteristics of socioeconomic deprivation (areal deprivation index [ADI]), the density of retail alcohol outlets for offsite consumption, while controlling for race/ethnicity, population density, and the percentage urban population.

RESULTS

The 63,451 non-MVC traumas within a 3761 mile2 study area encompassing PHX and 22 surrounding communities, an area with nearly 60% of the state's population and 54% of the trauma events in the AZ State Trauma Registry for the years 2013-2017. Adjusting for confounders, ADI was associated with the rates of non-MVC and assaultive traumas in all census block groups studied (mean coefficients 0.05 sd. 0.001 and 0.07 sd. 0.002 for non-MVC and assaultive trauma, respectively). Alcohol retail outlet density was also associated with non-MVC and assaultive traumas in fewer block groups compared to ADI.

CONCLUSION

Socioeconomic deprivation and alcohol outlet density were associated with injury producing events in the greater PHX area. These features persist in the environment before and after the traumas occur. Ongoing research is warranted to identify the most influential areal predictors of traumatic injury-causing events in the greater PHX area to inform and geographically target prevention initiatives.

Abstract D109: Helicobacter pylori infections in Navajo communities of Northern Arizona

Background: Helicobacter pylori (Hp) is a gastric pathogen associated with development of duodenal or stomach ulcers, stomach cancer, and mucosa associated lymphoid-tissue (MALT) lymphomas. While Hp prevalence is declining in many regions, it remains the leading infectious cause of cancer worldwide. In the United States prevalence varies by geographic location, ethnic background, socioeconomic status, and age. This pilot project seeks to understand the role of Hp infection in the development of stomach cancer among Native Americans of Northern Arizona, where stomach cancer incidence rates are approximately three times higher than the general Arizona population and it is the leading cause of cancer mortality. Methods: A cross-sectional survey based on a random sample of households selected using census block vectors for tribal lands overlaid onto satellite imagery. Potential household structures were marked and randomly sorted with recruitment goals set to be proportional to underlying population size. Houses were ‘ground-truthed’ for eligibility and residents approached for participation. A total of 72 households were recruited between June-August 2018 with 105 self-identified Navajo &gt;18 years old living in three communities in northern Arizona participating. Participants were assessed on household and individual level factors associated with infection. A urea breath test (UBT) was performed to test for active infection. We used logistic regression, adjusted for household clustering, to calculate odds ratios (aOR) and 95% confidence intervals (CI) for associations between UBT results and individual and household factors. Results: Active Hp infection was found in 66 of the 101 participants with valid UBT, crude prevalence of 65.4%. Male participants were more likely to be positive (aOR=2.89, 95% CI, 1.03-8.09). Participants with an unregulated household water source had the highest odds for positive UBT (aOR=8.85, 95% CI, 1.50-53.38). There was no association with age or education and a modest association with history of gallbladder disease. Only 23.8% reported they had ever heard of Hp infections and 12.9% previously tested for the infection. Conclusion: Prevalence of Hp is high among individuals in these Navajo communities. Use of household water that was not regulated, was strongly associated with active Hp infection. Further work is needed to determine if there is geographic variation and what Hp substrains are involved for this population. Attention also needs to focus on developing strategies to reduce the infection and target earlier detection.

Citation Format: Robin B Harris, Rachel Begay, Priscilla R Sanderson, Carmenlita Chief, Fernando Monroy, Heidi E Brown, Eyal Oren. Helicobacter pylori infections in Navajo communities of Northern Arizona [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr D109.

A Case-Control Study to Identify Community Venues Associated with Genetically-clustered, Multidrug-resistant Tuberculosis Disease in Lima, Peru

BACKGROUND

The majority of tuberculosis transmission occurs in community settings. Our primary aim in this study was to assess the association between exposure to community venues and multidrug-resistant (MDR) tuberculosis. Our secondary aim was to describe the social networks of MDR tuberculosis cases and controls.

METHODS

We recruited laboratory-confirmed MDR tuberculosis cases and community controls that were matched on age and sex. Whole-genome sequencing was used to identify genetically clustered cases. Venue tracing interviews (nonblinded) were conducted to enumerate community venues frequented by participants. Logistic regression was used to assess the association between MDR tuberculosis and person-time spent in community venues. A location-based social network was constructed, with respondents connected if they reported frequenting the same venue, and an exponential random graph model (ERGM) was fitted to model the network.

RESULTS

We enrolled 59 cases and 65 controls. Participants reported 729 unique venues. The mean number of venues reported was similar in both groups (P = .92). Person-time in healthcare venues (adjusted odds ratio [aOR] = 1.67, P = .01), schools (aOR = 1.53, P < .01), and transportation venues (aOR = 1.25, P = .03) was associated with MDR tuberculosis. Healthcare venues, markets, cinemas, and transportation venues were commonly shared among clustered cases. The ERGM indicated significant community segregation between cases and controls. Case networks were more densely connected.

CONCLUSIONS

Exposure to healthcare venues, schools, and transportation venues was associated with MDR tuberculosis. Intervention across the segregated network of case venues may be necessary to effectively stem transmission.

Ethnic Disparities in Gastric Cancer Presentation and Screening Practice in the United States: Analysis of 1997-2010 Surveillance, Epidemiology, and End Results-Medicare Data

BACKGROUND

Chronic infection with Helicobacter pylori (H. pylori) is the strongest risk factor for distal gastric cancer. Although gastric cancer incidence has decreased, variation by race and ethnicity is observed. This study describes gastric cancer presentation and screening services among Medicare patients by race/ethnicity, place of birth, and history of gastric cancer-related conditions.

METHODS

Using demographic, location, and disease staging information, extracted from the Surveillance, Epidemiology and End Results-Medicare gastric cancer database (1997-2010), we compared frequencies of gastric cancer-related conditions (e.g., peptic ulcer, gastric ulcer, gastritis) and screening (H. pylori testing and endoscopy) from inpatient and outpatient services claims by selected race/ethnicity and place of birth.

RESULTS

Data included 47,994 incident gastric cancer cases with Medicare claims. The majority (48.0%) of Asian/Pacific Islanders (API) were foreign-born, compared with non-Hispanic whites (NHW), Hispanics, and blacks (with 64.4%, 33.9%, and 72.9% U.S.-born, respectively). For NHWs, the most frequently diagnosed gastric cancer site was the cardia (35.6%) compared with <15% (P < 0.001) for APIs, Hispanics, and blacks. Although more than 57% of all cases had a history of gastric cancer-related conditions, H. pylori testing was reported in only 11.6% of those cases. H. pylori testing was highest for APIs (22.8%) and lowest for blacks (6.5%).

CONCLUSIONS

Noncardia gastric cancer, associated with H. pylori infection, was diagnosed more frequently among APIs, blacks, and Hispanics than NHWs. Testing for H. pylori was low among all gastric cancer cases despite evidence of risk factors for which screening is recommended. Studies are needed to increase appropriate testing for H. pylori among higher risk populations.

IMPACT

This study sheds light on poor screening practices despite presence of gastric cancer-related conditions.

Interventions to increase physical activity in children 0-5 years old: a systematic review, meta-analysis and realist synthesis

OBJECTIVE

The objective of the study is to evaluate the effectiveness of interventions to increase physical activity (PA) in 0-5 year olds and to determine what works, for whom, in what circumstances.

DESIGN

Systematic review, meta-analysis and realist synthesis.

DATA SOURCES

Embase and EBSCOhost (Academic Search Complete, CINAHL Complete, Global Health, MEDLINE Complete, PsycINFO, SPORTDiscus with full text), up to and including April 2017.

ELIGIBILITY CRITERIA

Published in a peer-reviewed English language journal; randomized or controlled trial design; aimed to increase children's PA levels; reported on objectively assessed PA in children between 0 and 5.9 years at baseline and post-intervention.

RESULTS

Thirty-four studies were included in the review, mostly conducted in the preschool/childcare setting. Meta-analyses showed an overall non-significant (Z = 0.04, p = 0.97) mean difference of 0.03 (95% CI = -1.57, 1.63) minutes/day for light-intensity PA (n = 11). The overall mean difference for moderate-intensity to vigorous-intensity PA (n = 21) was 2.88 (95% CI = 1.54, 4.23) minutes/day, indicating a small but significant overall positive effect (Z = 4.20, p < 0.001). The realist synthesis provided insights into the key contexts and mechanisms that appeared to be effective at changing children's PA.

CONCLUSION

Based on a quantitative and qualitative examination of the evidence, this review provides specific recommendations for effective early childhood PA interventions for practitioners and policymakers.

Summary results of the 2014-2015 DARPA Chikungunya challenge

Background: Emerging pathogens such as Zika, chikungunya, Ebola, and dengue viruses are serious threats to national and global health security. Accurate forecasts of emerging epidemics and their severity are critical to minimizing subsequent mortality, morbidity, and economic loss. The recent introduction of chikungunya and Zika virus to the Americas underscores the need for better methods for disease surveillance and forecasting.

Methods: To explore the suitability of current approaches to forecasting emerging diseases, the Defense Advanced Research Projects Agency (DARPA) launched the 2014–2015 DARPA Chikungunya Challenge to forecast the number of cases and spread of chikungunya disease in the Americas. Challenge participants (n=38 during final evaluation) provided predictions of chikungunya epidemics across the Americas for a six-month period, from September 1, 2014 to February 16, 2015, to be evaluated by comparison with incidence data reported to the Pan American Health Organization (PAHO). This manuscript presents an overview of the challenge and a summary of the approaches used by the winners.

Results: Participant submissions were evaluated by a team of non-competing government subject matter experts based on numerical accuracy and methodology. Although this manuscript does not include in-depth analyses of the results, cursory analyses suggest that simpler models appear to outperform more complex approaches that included, for example, demographic information and transportation dynamics, due to the reporting biases, which can be implicitly captured in statistical models. Mosquito-dynamics, population specific information, and dengue-specific information correlated best with prediction accuracy.

Conclusion: We conclude that with careful consideration and understanding of the relative advantages and disadvantages of particular methods, implementation of an effective prediction system is feasible. However, there is a need to improve the quality of the data in order to more accurately predict the course of epidemics.

Ethnic Disparities in Gastric Cancer Presentation and Screening Practice in the United States: An Analysis of 1997–2010 SEER-Medicare Data

Describe differences in Helicobacter pylori (H. pylori) screening among a Surveillance, Epidemiology and End Results (SEER)-Medicare elderly population by ethnicity, place of birth, and gastric cancer (GC)-related conditions, as chronic infection with H. pylori is the strongest risk factor for distal GC. Methods: We used the National Cancer Institute's population-based SEER-Medicare cancer database for GC (1997–2010). We extracted demographic, location and disease staging information from the SEER data file, Patient Entitlement and Diagnosis Summary File. We obtained information on frequencies of various GC-related conditions (e.g., peptic ulcer, gastric ulcer, gastritis) and screening (H. pylori testing and endoscopy) from inpatient hospital and physician/outpatient services claims. Results: Data from 34,730 subjects were analyzed. The majority of Asian American/Pacific Islanders (AAPIs), 65.1%, were foreign-born, while majority of Non-Hispanic Whites (NHW), Hispanics and Blacks were US-born (88.7%, 51.3%, and 96.9%, respectively). NHWs were oldest at diagnosis (74.7 y.); Hispanic and Black cases were the youngest (72.4 and 72.9 y., respectively). For NHWs, the most frequently diagnosed GC site was the cardia (36.1%), while for AAPIs, Hispanics and Blacks, the most diagnosed sites were non-cardia (&gt;80%, P &lt; 0.001). Over 55% of NHW, Hispanic and Black cases were diagnosed at regional or distant stage, while 55% of AAPIs were diagnosed at local or regional stage. Over 57% of all cases had a history of GC-related conditions (AAPIs were highest at 64.1%). However, only 11.2% of total cases showed evidence of H. pylori testing. H. pylori testing was more frequent for foreign-born than US-born (2-fold increase in proportions) and AAPIs exhibited the highest proportion of H. pylori testing (22.6% among those with a GC-related condition). Conclusions: Screening for H. pylori was low for all GC cases, despite race/ethnic groups exhibiting conditions for which H. pylori testing is recommended. AAPI GC cases had the highest frequency of H. pylori testing with tumors staged locally or regionally; increased testing could lead to earlier stage of tumor at diagnosis. Future studies should investigate why screening rates are low in patients with GC-related conditions.

A systematic review of methods to measure family co-participation in physical activity

The family environment is key in influencing children's health behaviours. Encouraging family co-participation in physical activity may therefore be an effective approach to increasing children's physical activity levels. Yet, little is known about how to best assess family co-participation in physical activity. This review summarizes methods to measure family co-participation in physical activity, which was defined as joint physical activities including at least one healthy child (0-18 years) and one other family member. Methods were identified through a systematic literature search, cross-referencing pre-selected reviews and contacting research groups. Thirty-seven measurement methods were included. Questionnaires were the most common method used, with the majority assessing frequency of co-participation and few also assessing duration and type. Reliability and internal consistency of scales were often reported, but rarely specified for the item(s) relevant to co-participation. Other methods of measuring co-participation included diaries, event history calendars, direct observations and accelerometry combined with diary, ecological momentary assessment or global positioning systems (GPS). Whilst a large number of measurement methods of family co-participation in physical activity exist, few are comprehensive and/or report acceptable psychometric properties. Future work should focus on reaching consensus in defining family co-participation in physical activity, and subsequently developing reliable and valid measures.

Workplace availability, risk group and perceived barriers predictive of 2016-17 influenza vaccine uptake in the United States: A cross-sectional study

BACKGROUND

Seasonal influenza, though mostly self-limited in the healthy adult, may lead to severe disease and/or complications in subpopulations. Annual influenza vaccination is available in many countries with coverage goals rarely being met. We conducted a cross-sectional study of influenza vaccine uptake and explored socio-demographic, economic, and psychological factors that explained vaccine uptake.

METHODS

The survey was administered via Amazon Mechanical Turk (MTurk) to United States residents in January 2017, using the Qualtrics platform. Using principal axis factor analysis, we reduced the 25 items theory-based psychological determinants into the primary constructs they measure if/when internal consistency was sufficient (Cronbach's alpha >0.60). Logistic regression models were used to quantify the association of socio-demographic, economic, and psychological factors with reported vaccine behavior in the 2016-17 flu season.

RESULTS

1007 participants completed the survey, sex distribution was even, 67% had 25-44years of age, and 61% annual household income of $30-99 thousand United States dollars. About 25% had the flu shot offered at their workplace and 20% reported belonging to a group for whom the flu shot is recommended. Vaccine uptake was 31.5%. Eight predictors remained in the final adjusted model (R²=0.489), having the vaccine offered at the workplace, belonging to a group for whom the vaccine is recommended, and higher perceived barriers were the strongest predictors of vaccine uptake, increasing (and decreasing in the case of barriers) the odds by >3-fold. Additionally, higher household income, higher perceived susceptibility and higher perceived benefits also independently predicted vaccine uptake.

DISCUSSION

We found evidence that perceived barriers significantly impaired vaccine uptake to the same extent that having the vaccine offered at the workplace or belonging to a group for whom the vaccine is recommended facilitated uptake. Ideally, a better understanding of drivers of vaccine hesitancy will result in improved interventions to increase vaccine uptake.

Habitat and Density of Oviposition Opportunity Influences Aedes aegypti (Diptera: Culicidae) Flight Distance

Understanding the dispersal of Aedes (aegypti (L.) Diptera: Culicidae) after consuming a potentially infectious bloodmeal is an important part of controlling the spread of the arboviruses it transmits. Because of the impact on abundance, removal of oviposition sites is a key component of vector control. However, source reduction around a case may encourage dispersal of potentially infected vectors. We compare the effect of oviposition site availability on Ae. aegypti dispersal behavior within 30-m linear cages in three model ecosystems at the University of Arizona's Biosphere 2 research facility. We found a significant interaction effect in which, when oviposition site density was sparse, dispersal was greater in the highly vegetated humid rainforest and limited in the low vegetation, arid desert model ecosystem. When oviposition site density was dense, no significant effect on dispersal was observed. These analyses support the idea that source reduction has an important influence on the distance that gravid, potentially infected, females will travel.

Aedes aegypti (Diptera: Culicidae) Abundance Model Improved With Relative Humidity and Precipitation-Driven Egg Hatching

We propose an improved Aedes aegypti (L.) abundance model that takes into account the effect of relative humidity (RH) on adult survival, as well as rainfall-triggered egg hatching. The model uses temperature-dependent development rates described in the literature as well as documented estimates for mosquito survival in environments with high RH, and for egg desiccation. We show that combining the two additional components leads to better agreement with surveillance trap data and with dengue incidence reports in various municipalities of Puerto Rico than incorporating either alone or neither. Capitalizing on the positive association between disease incidence and vector abundance, this improved model is therefore useful to estimate incidence of Ae. aegypti-borne diseases in locations where the vector is abundant year-round.

Effect of Temperature Thresholds on Modeled Aedes aegypti (Diptera: Culicidae) Population Dynamics

Dynamic simulation models provide vector abundance estimates using only meteorological data. However, model outcomes may heavily depend on the assumptions used to parameterize them. We conducted a sensitivity analysis for a model of Aedes aegypti (L.) abundance using weather data from two locations where this vector is established, La Margarita, Puerto Rico and Tucson, Arizona. We tested the effect of simplifying temperature-dependent development and mortality rates and of changing development and mortality thresholds as compared with baselines estimated using biophysical models. The simplified development and mortality rates had limited effect on abundance estimates in either location. However, in Tucson, where the vector is established but has not transmitted viruses, a difference of 5 °C resulted in populations either surviving or collapsing in the hot Arizona mid-summer, depending on the temperature thresholds. We find three important implications of the observed sensitivity to temperature thresholds. First, this analysis indicates the need for better estimates of the temperature tolerance thresholds to refine entomologic risk mapping for disease vectors. Second, our results highlight the importance of extreme temperatures on vector survival at the marginal areas of this vector's distribution. Finally, the model suggests that adaptation to warmer temperatures may shift regions of pathogen transmission.

Management of Helicobacter Pylori in the United States: Results from a national survey of gastroenterology physicians

BACKGROUND AND AIMS

We sought to determine current knowledge and practices among gastroenterology physicians and assess adherence to current guidelines for H. pylori management.

METHODS

Online surveys were distributed in 2014 to practicing gastroenterology physicians for information related to the diagnosis and treatment of H. pylori infection.

RESULTS

A total of 582 completed surveys were reviewed. The H. pylori screening test used "almost always" was gastric biopsy obtained during endoscopy (histology) (59%) followed by stool antigen test (20%). Standard triple therapy for 14days was commonly prescribed by 53% of respondents. The stool antigen test was most frequently chosen to confirm H. pylori eradication (51%), although only 58% of physicians checked for eradication in patients who underwent treatment.

CONCLUSIONS

Adherence to current American College of Gastroenterology guidelines is low. Although more physicians treat patients with a positive H. pylori test, only half ensure eradication after treatment. Improving knowledge of the resistance patterns of H. pylori may be critical to ensure successful eradication.

Population Knowledge, Attitude, and Practice Regarding Helicobacter pylori Transmission and Outcomes: A Literature Review

BACKGROUND

Helicobacter pylori infection is associated with the development of chronic gastritis, peptic ulcer disease, and gastric cancer. Current clinical recommendations are that H. pylori test-and-treat should be individualized based on comorbidities and patient preferences among populations at increased risk for certain morbidities. However, knowledge, attitudes and practices regarding H. pylori among potential patient populations are largely unknown.

MATERIALS

We conducted a literature review to assess knowledge, attitudes, and practices of patients or community populations around H. pylori transmission, prevention, and associated morbidity.

RESULTS

Nine studies met the inclusion criteria, all published between 1997 and 2014. Eight studies evaluated perception of H. pylori among at-risk populations, while one study evaluated perception among a general population. The studies suggest inconsistencies between the perceptions of these populations and the established understanding of knowledge, attitude, and preventive practices for H. pylori among even at-risk populations.

CONCLUSION

To adequately respond to current test-and-treat recommendations for treatment of H. pylori, general population education must be implemented, especially among at-risk populations. Further work is needed within at-risk populations in the United States to determine prevalence of H. pylori and their current knowledge if adequate prevention strategies are to be designed.

Spatio-temporal and neighborhood characteristics of two dengue outbreaks in two arid cities of Mexico

Little is currently known about the spatial-temporal dynamics of dengue epidemics in arid areas. This study assesses dengue outbreaks that occurred in two arid cities of Mexico, Hermosillo and Navojoa, located in northern state of Sonora. Laboratory confirmed dengue cases from Hermosillo (N=2730) and Navojoa (N=493) were geocoded by residence and assigned neighborhood-level characteristics from the 2010 Mexican census. Kernel density and Space-time cluster analysis was performed to detect high density areas and space-time clusters of dengue. Ordinary Least Square regression was used to assess the changing socioeconomic characteristics of cases over the course of the outbreaks. Both cities exhibited contiguous patterns of space-time clustering. Initial areas of dissemination were characterized in both cities by high population density, high percentage of occupied houses, and lack of healthcare. Future research and control efforts in these regions should consider these space-time and socioeconomic patterns.

Influence of the Length of Storage on Aedes aegypti (Diptera: Culicidae) Egg Viability

Aedes aegypti (L.) is one of the most important arboviral vectors worldwide. Vector control is targeted at immature and adult stages; however, eggs are resistant to desiccation and may repopulate treated areas long after treatment ceases. We investigated the effect of age on Ae. aegypti egg hatching rates using newly colonized populations (F2) from an arid region. We found a strongly negative association where older eggs had lower hatch rates. The capacity of eggs to survive for long periods of time has implications on mosquito control. In addition, the accumulation of eggs in containers should be accounted for in abundance modeling efforts where populations may grow rapidly early in the season.

Supplementing a yeast probiotic to pre-weaning Holstein calves: Feed intake, growth and fecal biomarkers of gut health

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Efficacy of Saccharomyces cerevisiae boulardii (SCB) fed to calves was evaluated.

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SCB was supplemented in milk replacer and fed to healthy pre-weaned Holstein calves.

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No significant difference was observed in calf performance and health scores.

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No significant difference was observed in fecal biomarkers of gut health.

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No enteric and/or respiratory challenge was observed throughout the trial.

Diarrhea, resulting from gastrointestinal infection by pathogens, is a common cause of the high mortality and morbidity of neonatal calves. The objective of this study was to evaluate the effects of supplementing a yeast product in milk replacer (MR) on growth and health of calves, and on fecal populations of some targeted microorganisms related to calf health and growth (i.e., total bacteria, Escherichia coli, Clostridium cluster XIVa, Faecalibacterium prausnitzii and Bifidobacterium spp.). We hypothesized that feeding a Saccharomyces cerevisiae var boulardii (SCB) product would improve gastrointestinal health and growth performance of calves. Forty-two Holstein bull calves (42.6 ± 0.77 kg at birth) were randomly assigned on day 2 of age to either a control or SCB treatment. The SCB was supplemented in MR and fed at 5 g/d per head to supply 10 billion colony-forming units per day. All calves received high quality colostrum (>50 mg/mL of immunoglobulin G) during the first 24 h of life, and were fed with 8 L MR (150 g/L mixed with 40 °C water) daily from day 2–35, and 4 L daily from day 35–42. Calves were also fed calf starter ad libitum from day 7–56. Daily MR and starter offered and refused, daily fecal scores, nasal scores, ear scores, and weekly body weight of calves were recorded. Fecal samples were collected on day 7, 35 and 56 after the first feeding of that day for microbial targets analysis. Overall, there is no serious disease challenge for all the calves during the entire experimental period. No differences were observed in MR intake, starter intake, metabolizable energy (ME) intake, average daily gain, ME intake to gain ratio, fecal score, nasal score, eye score or any targeted microorganisms between treatments throughout the experiment. These results suggest that supplementing SCB in MR has no additive effects on animal growth or fecal biomarkers of gut health when calves do not show deteriorated health status.

Data-driven outbreak forecasting with a simple nonlinear growth model

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We present EpiGro, a simple data-driven method to forecast the scope of an ongoing outbreak.

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We provide general hypotheses for expected model validity and also discuss model limitations.

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We propose an automated parameter estimation method that can be used for forecasting.

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We test our approach on 9 different outbreaks and show robustness over multiple systems and over noisy data sets.

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In the absence of other information or in conjunction with other models, EpiGro may be useful to public health responders.

Recent events have thrown the spotlight on infectious disease outbreak response. We developed a data-driven method, EpiGro, which can be applied to cumulative case reports to estimate the order of magnitude of the duration, peak and ultimate size of an ongoing outbreak. It is based on a surprisingly simple mathematical property of many epidemiological data sets, does not require knowledge or estimation of disease transmission parameters, is robust to noise and to small data sets, and runs quickly due to its mathematical simplicity. Using data from historic and ongoing epidemics, we present the model. We also provide modeling considerations that justify this approach and discuss its limitations. In the absence of other information or in conjunction with other models, EpiGro may be useful to public health responders.

Mosquito Avoidance Practices and Knowledge of Arboviral Diseases in Cities with Differing Recent History of Disease

As the range of dengue virus (DENV) transmission expands, an understanding of community uptake of prevention and control strategies is needed both in geographic areas where the virus has recently been circulating and in areas with the potential for DENV introduction. Personal protective behaviors such as the use of mosquito repellent to limit human-vector contact and the reduction of vector density through elimination of oviposition sites are the primary control methods for Aedes aegypti, the main vector of DENV. Here, we examined personal mosquito control measures taken by individuals in Key West, FL, in 2012, which had experienced a recent outbreak of DENV, and Tucson, AZ, which has a high potential for introduction but has not yet experienced autochthonous transmission. In both cities, there was a positive association between the numbers of mosquitoes noticed outdoors and the overall number of avoidance behaviors, use of repellent, and removal of standing water. Increased awareness and perceived risk of DENV were associated with increases in one of the most effective household prevention behaviors, removal of standing water, but only in Key West.

Family-based interventions to increase physical activity in children: a systematic review, meta-analysis and realist synthesis

OBJECTIVE

Family-based interventions represent a potentially valuable route to increasing child physical activity (PA) in children. A dual meta-analysis and realist synthesis approach examined existing interventions to assist those developing programmes to encourage uptake and maintenance of PA in children.

DESIGN

Studies were screened for inclusion based on including participants aged 5-12 years, having a substantive aim of increasing PA by engaging the family and reporting on PA outcome. Duplicate data extraction and quality assessment were conducted. Meta-analysis was conducted in STATA. Realist synthesis included theory development and evidence mapping.

RESULTS

Forty-seven studies were included, of which three received a 'strong' quality rating, 21 'moderate' and 23 'weak'. The meta-analysis (19 studies) demonstrated a significant small effect in favour of the experimental group (standardized mean difference: 0.41; 95%CI 0.15-0.67). Sensitivity analysis, removing one outlier, reduced this to 0.29 (95%CI 0.14-0.45). Realist synthesis (28 studies) provided insight into intervention context (particularly, family constraints, ethnicity and parental motivation), and strategies to change PA (notably, goal-setting and reinforcement combined).

CONCLUSION

This review provides key recommendations to inform policy makers and other practitioners in developing evidence-based interventions aimed at engaging the family to increase PA in children, and identifies avenues for future research.

Abstract B23: Chemoproteomic profiling of native kinases during the treatment of cells with kinase inhibitors

Kinases are an important class of targets for a number of therapeutic indications, and currently, kinase inhibitors constitute a significant fraction of recently approved drugs, particularly for cancer. Using a probe-based chemoproteomics platform, we have demonstrated the utility of the platform to monitor the interactions between inhibitors and native kinases. Herein, we profile kinase inhibitors in cell lines either sensitive or resistant to the compound for various periods of time. We observe that at early time points, inhibitor profiles for a compound are qualitatively similar in both the sensitive and resistant cells, suggesting the compound is capable of engaging its direct targets in both cell types. In contrast, at later time points, additional kinases are observed affected by compound treatment. We infer that these kinases do not directly bind the compound but rather reflect secondary effects that result from the engagement of the primary targets (pathway effects). Significantly, the pathway effects are only observed in the sensitive cells and not the resistant cells. Kinases affected through these pathway effects include kinases known to be critical for cell cycle progression including CDK1, Aurora A and B, PLK1, and MASTL. Finally, we demonstrate that during the treatment of tumor-bearing mice with an inhibitor, in addition to inhibition of the direct targets, pathway effects are observed recapitulating the results from the cell-based studies.

Citation Format: Tyzoon K. Nomanbhoy, Heidi E. Brown, Jiangyue Wu, Subha Vogeti, Arwin Aban, Wendy Grant, Alemayehu Senait, Shuzhen Wu, Christa Dias, Geeta Sharma. Chemoproteomic profiling of native kinases during the treatment of cells with kinase inhibitors. [abstract]. In: Proceedings of the Fourth AACR International Conference on Frontiers in Basic Cancer Research; 2015 Oct 23-26; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2016;76(3 Suppl):Abstract nr B23.

Serologic Evidence for Fecal-Oral Transmission of Helicobacter pylori

Helicobacter pylori infection is among the most prevalent infections in the world and a key cause of gastric diseases; however, its route of transmission remains unclear. This study aimed to assess the potential for fecal-oral transmission of H. pylori by leveraging its association with a disease with known etiology. Utilizing serology data from the National Health and Nutrition Examination Survey (NHANES 1999; N = 6,347), the association between H. pylori and hepatitis A virus (HAV), a sensitive indicator for fecal-oral exposure, was assessed. Survey-weighted kappa and multiple logistic regression were used to quantify the association between H. pylori and HAV after controlling for age, sex, race, poverty, birthplace, crowding, smoking, and alcohol use. Concordant serological results were found among 69.8% of participants (survey-weighted κ = 0.30, 95% confidence interval [CI] = 0.26, 0.35). The adjusted odds of H. pylori seropositivity were over two times higher after adjusting for confounders (odds ratio = 2.27, 95% CI = 1.79, 2.87). Results from this study suggest H. pylori and HAV infections are strongly associated. Since HAV is primarily transmitted through the fecal-oral route, fecal-oral transmission may be an important pathway for H. pylori spread.

A Critical Assessment of Officially Reported Chagas Disease Surveillance Data in Mexico

OBJECTIVE

Chagas disease, a disease caused by Trypanosoma cruzi, disproportionately affects poor people throughout Latin America. In Mexico, assessments of officially reported burden have not been previously reported. To evaluate discontinuity between surveillance data and data from other sources, we used data from the Mexican Ministry of Health to describe the distribution of reported Chagas disease over time in Mexico and compare it with estimates from the literature.

METHODS

We summarized age and sex differences for Chagas cases and mortality for 1995-2013 and 1982-2010, respectively. We examined the spatial distribution of Chagas disease over time with respect to disease burden. We further compared officially reported figures with estimates from the literature.

RESULTS

Among 6,494 officially reported cases, rates of Chagas disease were highest in adults aged 25-44 years (47.3%). Mortality was highest in adults aged ≥45 years (423/495, 85.5%). The data indicated increasing temporal trends for incidence and mortality. The greatest burden occurred in southern states, with increasing spatial distribution over time. Fewer than 900 cases and 40 deaths were officially reported annually, in contrast to estimates from the literature of approximately 69,000 new cases and 25,000 deaths annually.

CONCLUSION

While increasing trends in officially reported data have been observed, large discrepancies in case estimates compromise our understanding of Chagas disease epidemiology. Reported cases based on current practices are not enough to correctly assess the Chagas disease burden and spatial distribution in Mexico. Understanding the true epidemiology of this disease will lead to more focused and successful control and prevention strategies to decrease disease burden.

Projection of Climate Change Influences on U.S. West Nile Virus Vectors

While estimates of the impact of climate change on health are necessary for health care planners and climate change policy makers, models to produce quantitative estimates remain scarce. We describe a freely available dynamic simulation model parameterized for three West Nile virus vectors, which provides an effective tool for studying vector-borne disease risk due to climate change. The Dynamic Mosquito Simulation Model is parameterized with species specific temperature-dependent development and mortality rates. Using downscaled daily weather data, we estimate mosquito population dynamics under current and projected future climate scenarios for multiple locations across the country. Trends in mosquito abundance were variable by location, however, an extension of the vector activity periods, and by extension disease risk, was almost uniformly observed. Importantly, mid-summer decreases in abundance may be off-set by shorter extrinsic incubation periods resulting in a greater proportion of infective mosquitoes. Quantitative descriptions of the effect of temperature on the virus and mosquito are critical to developing models of future disease risk.

Characteristics of Wind-Infective Farms of the 2006 Bluetongue Serotype 8 Epidemic in Northern Europe

Bluetongue is a Culicoides-borne viral disease of livestock. In 2006, northern Europe experienced a major outbreak of this disease with devastating effects on the livestock industry. The outbreak quickly spread over the region, primarily affecting cattle and sheep. A previous analysis of the role of vector flight and wind in the spread of this virus across northern Europe indicated that infection at 1,326 (65%) of the reported infected farms could be traced back to just 599 (29%) farms (wind-infective farms). Rather than focusing on presence or absence of vectors or difference between infected and non-infected farms, we investigate the zoological and environmental characteristics of these 599 wind-infective farms (which can be thought of as super-spreaders) in order to characterize what makes them distinct from non-infective farms. Differences in temperature, precipitation, and the density of sheep at individual farms were identified between these two groups. These environmental and zoological factors are known to affect vector abundance and may have promoted bluetongue virus transmission. Identifying such ecological differences can help in the description and quantification of relative risk in affected areas.