Standardization of a multiplex assay to identify weak D types in a mixed-race Brazilian population.

RH allele variability is caused by several types of variants, resulting in altered RhD and RhCE phenotypes. Most of the weak D phenotypes in European-derived populations are weak D types 1, 2, or 3, which are not involved in alloimmunization episodes. However, the Brazilian population is racially diverse, and the accuracy of molecular and serologic tests developed in recent years has allowed for the identification of other RH variants, that are common in the Brazilian population, such as weak D type 38 or weak partial 11, the latter involved in alloimmunization cases. Furthermore, patients with these two weak D variants must be transfused with D- red blood cell units, as do patients with weak D type 4 or DAR, which are also common D variants in Brazil. Weak D type 38 and weak partial 11 can be serologically misclassified as weak D types 1, 2, or 3 in patients, based on European experience, or as D- in donors. Additionally, pregnant women may unnecessarily be identified as requiring Rh immune globulin. RhCE phenotypes are reliable indicators of RhD variants. For individuals with the Dce phenotype, the preferred approach is to specifically search for RHD*DAR. However, when encountering DCe or DcE phenotypes, we currently lack a developed method that assists us in rapidly identifying and determining the appropriate course of action for the patient or pregnant woman. Two multiplex assays were proposed: one for the identification of RHD*weak partial 11, RHD*weak D type 38, and RHD*weak D type 3 and another for RHD*weak D type 2 and RHD*weak D type 5. The multiplex assays were considered valid if the obtained results were equivalent to those obtained from sequencing. Expected results were obtained for all tested samples. The proposed multiplex allele-specific polymerase chain reaction assays can be used in the molecular investigation of women of childbearing age, patients, and blood donors presenting a weak D phenotype with DCe or DcE haplotypes in a mixed-race population, such as Brazil.

Isolation, characterization, and experimental infection of Streptococcus gallolyticus subspecies pasteurianus from commercial turkeys with acute septicemia: a pilot study.

Streptococcus gallolyticus (SG) is a Gram-positive cocci found as commensal gut flora in animals and humans. SG has emerged as a cause of disease in young poults between 1 and 3 wk of age. SG is associated with septicemia resulting in acute mortality with no premonitory signs in turkeys. Three SG isolates were obtained from clinical field cases of acute septicemia of commercial turkeys and used in three independent experiments. In Experiment 1, embryos were inoculated 25 d of embryogenesis with varying concentrations of SG1, SG2, or SG3. In Experiment 2, day of hatch, poults were inoculated with varying concentrations using different routes of administration of SG1, SG2, or SG3. In Experiment 3, day of hatch, poults were inoculated with only isolate SG1 using different paths. Poults were randomly selected for necropsy on d 8 and d 15 and sampled to collect spleen, heart, and liver for SG on d 21, the remaining poults were necropsied and cultured. Samples were plated on Columbia nalidixic acid and colistin agar (CNA) (40°C, 18-24 h). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) confirmed suspect colonies. Data were analyzed using the chi-square test of independence, testing all possible combinations to determine significance (P < 0.05). Weight data were subjected to ANOVA using JMP with significance (P < 0.05). No differences were found in BW or BWG on d 0, 8, 15, or 22. Splenomegaly, focal heart necrosis, and pericarditis were observed in all groups in experiments 1 through 3. In Experiment 3, only airsacculitis was observed in a negative control in separate isolation (P > 0.05). On d 21 of Experiment 3, increased (P < 0.05) recovery of SG from spleens were observed in co-housed negative controls, as well as poults challenged by oral gavage (P > 0.05 for d 7 and d 14). These results confirm numerous previous studies indicating that SG subsp. pasteurianus is a primary infectious microorganism that causes septicemia in young poults.

Antimalarial Agents Derived from Metal-Amodiaquine Complexes with Activity in Multiple Stages of the Plasmodium Life Cycle.

Malaria is the one of the deadliest infectious diseases worldwide. Chemically, quinolines are excellent ligands for metal coordination and are deployed as drugs for malaria treatment. There is a growing body of evidence indicating that metal complexes can be conjugated with antimalarial quinolines to be used as chemical tools to overcome the disadvantages of quinolines, improving their bioactive speciation, cellular distribution, and subsequently broadening the spectrum of activity to multiple stages of the complex Plasmodium life cycle. In this study, four novel complexes of ruthenium(II)- and gold(I)-containing amodiaquine (AQ) were synthesized, and a careful chemical characterization revealed the precise coordination site of AQ to the metals. Their speciation in solution was investigated, demonstrating the stability of the quinoline-metal bond. RuII - and AuI -AQ complexes were demonstrated to be potent and efficacious in inhibiting parasite growth in multiple stages of the Plasmodium life cycle as assayed in vitro and in vivo. These properties could be attributed to the ability of the metal-AQ complexes to reproduce the suppression of heme detoxification induced by AQ, while also inhibiting other processes in the parasite life cycle; this can be attributed to the action of the metallic species. Altogether, these findings indicate that metal coordination with antimalarial quinolines is a potential chemical tool for drug design and discovery in malaria and other infectious diseases susceptible to quinoline treatment.

Infiltration OF 5Y-PSZ with thermally compatible glass: Strength, microstructure and failure mode analyses.

This study set out to develop a thermally compatible glass to be infiltrated into zirconia partially stabilized by yttrium oxide (5Y-PSZ), to characterize it, and to evaluate its structural reliability and mechanical behavior. 5Y-PSZ zirconia discs (N = 90), dimensions 1.5 mm × 15 mm were produced, polished with #600 alumina oxide and #1200 silicon carbide sandpaper in a polisher. Three groups of 5Y-PSZ discs were assigned (n = 30): Zctrl: as sintered zirconia, Zinf-comp: glass-infiltrated zirconia on the occlusal surface, and sintered, and Zinf-tens: glass-infiltrated zirconia on the cementing surface and sintered; for biaxial flexural strength testing (ISO 6872:2015). A gel was synthesized via the sol-gel method and applied to the ceramic surface. Mechanical assay data (MPa) were evaluated via Weibull analysis (α = 5%) and specimens via X-Ray Diffractometry (XRD), Scanning Electron Microscopy (SEM), and fractographic analysis. The Zinf-tens group showed a characteristic strength of 824 MPa and m = 9.9; Zinf-comp 613 MPa and m = 10.2; Zctrl 534 MPa and m = 8; all groups differed statistically (σ0). However, they were similar in structural homogeneity (m). XRD showed 20-50 µm of infiltration, which means dissolution of part of the yttrium and reduction in the size of the cubic grains. In addition, the Zinf-tens group presented a failure origin from inside the material. The developed glass infiltrated into zirconia partially stabilized by yttrium oxide, increasing its characteristic strength and structural homogeneity by reducing surface defects and changing the failure mode.

Cambios en la masa ósea en una población infantil con diabetes mellitus tipo 1. Estudio longitudinal / Changes in bone mass in a paediatric population with type 1 diabetes mellitus. Longitudinal study

Objetivo: Evaluar, a lo largo de un seguimiento de 79,2 meses, el comportamiento de la densidad mineral ósea (DMO) determinada mediante Densitometría Axial Computarizada (DXA), la densidad mineral ósea volumétrica (DMOvol) y su relación con los datos antropométricos, junto con los parámetros relativos al metabolismo óseo (calcio, fósforo, fosfatasa alcalina, parathormona (PTH) y vitamina D (25-OH-D3)) en una población infantil con Diabetes Mellitus Tipo 1 (DM1) sin complicaciones microvasculares y un grupo control de referencia de similares características.Material y métodos: Inicialmente, se realizó un estudio transversal en 40 niños diabéticos (edad media 9,4±2,8 años) y 108 controles (9,3±1,5 años) para valorar las posibles diferencias entre ambas poblaciones. 26 pacientes del grupo diabético inicial, fueron reevaluados tras 79,2 meses de seguimiento.Resultados: Se observó que, al inicio, la masa ósea fue similar en los diabéticos y controles. Después del seguimiento, la DMO de los niños diabéticos era muy inferior a la esperada en población infantil no diabética.El peso, la altura y el Índice de Masa Corporal (IMC) siguieron el mismo patrón que la DMO. Los valores de calcio, fósforo, fosfatasa alcalina, PTH y vitamina D, aunque en rango de normalidad, fueron más bajos que en los controles. La fosfatasa alcalina no se incrementó en el periodo puberal.Conclusiones: El presente estudio demuestra que los niños y adolescentes con un diagnóstico reciente de DM1 tienen una DMO normal. Sin embargo, con el paso del tiempo, y sobre todo durante la adolescencia, muestran una menor ganancia de masa ósea y alteraciones en los parámetros de recambio óseo. (AU)

Aberrant hippocampal transmission and behavior in mice with a stargazin mutation linked to intellectual disability.

Mutations linked to neurodevelopmental disorders, such as intellectual disability (ID), are frequently found in genes that encode for proteins of the excitatory synapse. Transmembrane AMPA receptor regulatory proteins (TARPs) are AMPA receptor auxiliary proteins that regulate crucial aspects of receptor function. Here, we investigate a mutant form of the TARP family member stargazin, described in an ID patient. Molecular dynamics analyses predicted that the ID-associated stargazin variant, V143L, weakens the overall interface of the AMPAR:stargazin complex and impairs the stability of the complex. Knock-in mice harboring the V143L stargazin mutation manifest cognitive and social deficits and hippocampal synaptic transmission defects, resembling phenotypes displayed by ID patients. In the hippocampus of stargazin V143L mice, CA1 neurons show impaired spine maturation, abnormal synaptic transmission and long-term potentiation specifically in basal dendrites, and synaptic ultrastructural alterations. These data suggest a causal role for mutated stargazin in the pathogenesis of ID and unveil a new role for stargazin in the development and function of hippocampal synapses.

Clinical effectiveness and bacteriological eradication of three different Short-COurse antibiotic regimens and single-dose fosfomycin for uncomplicated lower Urinary Tract infections in adult women (SCOUT study): study protocol for a randomised clinical trial.

INTRODUCTION: Uncomplicated lower urinary tract infections (uLUTI) are a common problem in primary care. Current local guidelines recommend the use of a single 3 g dose of fosfomycin. However, most general practitioners (GP) prefer short-course therapies to single-dose therapy. No study has compared head-to-head short-course antimicrobial agents for uLUTIs. Therefore, the aim of this randomised clinical trial is to compare three different short-course antibiotic therapies with a single-dose of fosfomycin for these infections. METHODS AND ANALYSIS: This will be a pragmatic, multicentre, parallel group, open trial. Women aged 18 or older and with symptoms of uLUTI and a positive urine dipstick analysis will be randomised to one of the following four groups: a single dose of 3 g of fosfomycin, 2 days of 3 g of fosfomycin o.d., 3 days of pivmecillinam 400 mg three times per day (t.i.d) or 5 days of nitrofurantoin 100 mg t.i.d. A total sample of 1120 patients was calculated. The primary endpoint is clinical effectiveness at day 7, defined as cure of symptoms reported by the patients in a diary including four symptoms: dysuria, urgency, frequency and suprapubic pain, which will be scored on a 4-point severity scale (not present/mild/moderate/severe). Follow-up visits are scheduled at days 7 (phone call), 14 and 28 for assessing evolution. Urine samples will be collected in the three on-site visits and urine cultures performed. If positive, antibiograms for the three antibiotics studied will be performed. Bacterial eradication will be measured at days 14 and 28. ETHICS AND DISSEMINATION: The study was approved by the Ethical Board of IDIAP Jordi Gol (reference number: 21/173-AC) and Spanish Agency of Medicines and Medical Devices. The findings of this trial will be disseminated through research conferences and peer-review journals. TRIAL REGISTRATION NUMBER: NCT04959331; EudraCT Number: 2021-001332-26. TIME SCHEDULE: January 2022 to April 2023.

Impact of replacing sedentary behaviour with other movement behaviours on depression and anxiety symptoms: a prospective cohort study in the UK Biobank.

BACKGROUND: Sedentary behaviour is potentially a modifiable risk factor for depression and anxiety disorders, but findings have been inconsistent. To assess the associations of sedentary behaviour with depression and anxiety symptoms and estimate the impact of replacing daily time spent in sedentary behaviours with sleep, light, or moderate to vigorous physical activity, using compositional data analysis methods. METHODS: We conducted a prospective cohort study in 60,235 UK Biobank participants (mean age: 56; 56% female). Exposure was baseline daily movement behaviours (accelerometer-assessed sedentary behaviour and physical activity, and self-reported total sleep). Outcomes were depression and anxiety symptoms (Patient Health Questionnaire-9 and Generalised Anxiety Disorders-7) at follow-up. RESULTS: Replacing 60 min of sedentary behaviour with light activity, moderate-to-vigorous activity, and sleep was associated with lower depression symptom scores by 1.3% (95% CI, 0.4-2.1%), 12.5% (95% CI, 11.4-13.5%), and 7.6% (95% CI, 6.9-8.4%), and lower odds of possible depression by 0.95 (95% CI, 0.94-0.96), 0.75 (95% CI, 0.74-0.76), and 0.90 (95% CI, 0.90-0.91) at follow-up. Replacing 60 min of sedentary behaviour with moderate-to-vigorous activity and sleep was associated with lower anxiety symptom scores by 6.6% (95% CI, 5.5-7.6%) and 4.5% (95% CI, 3.7-5.2%), and lower odds of meeting the threshold for a possible anxiety disorder by 0.90 (95% CI, 0.89-0.90) and 0.97 (95%CI, 0.96-0.97) at follow-up. However, replacing 60 min of sedentary behaviour with light activity was associated with higher anxiety symptom scores by 4.5% (95% CI, 3.7-5.3%) and higher odds of a possible anxiety disorder by 1.07 (95% CI, 1.06-1.08). CONCLUSIONS: Sedentary behaviour is a risk factor for increased depression and anxiety symptoms in adults. Replacing sedentary behaviour with moderate-to-vigorous activity may reduce mental health risks, but more work is necessary to clarify the role of light activity.

Lactobacillus paracasei DTA81, a cholesterol-lowering strain having immunomodulatory activity, reveals gut microbiota regulation capability in BALB/c mice receiving high-fat diet.

AIMS: In-vitro/In-vivo evaluation of cholesterol-lowering probiotic strain Lactobacillus paracasei DTA81 and the possible connection with the gut microbiota modulation. METHODS AND RESULTS: In the present study, strain DTA81 has been evaluated for the possible influence on blood lipid and glucose concentrations, modulation of the immune system, gastrointestinal survivability and modulation of gut microbiota in BALB/c mice receiving a high-fat diet. After 6 weeks of treatment, a significant reduction of total cholesterol and fasting blood sugar (FBS) among animals treated with L. paracasei DTA81 has been recorded. Comparison of colon tissue levels of different cytokines revealed a significant reduction of the inflammatory cytokine interleukin-6. The comparison of gut microbiota using the 16S rRNA approach indicated that the treatment with L. paracasei DTA81 significantly increased the taxa Bacteroidetes and Coprococcus. Moreover, the genome of DTA81 was sequenced for the in-silico assessment, and the analysis indicated the presence of cholesterol assimilation-related genes as well as the absence of negative traits such as transmissible antibiotic resistance genes, plasmids and prophage regions. CONCLUSION: The outcome of this study revealed the in-vitro and in-vivo properties of L. paracasei DTA81 and the possible mechanism between consumption of this strain, the abundance of Bacteriodetes/Coprococcus taxa, immunomodulatory activity and the subsequent reduction of cholesterol/FBS in BALB/c mice. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus paracasei DTA81 as a non-pharmacological potential probiotic supplement can influence metabolic homeostasis in individuals, particularly those adopting high-fat diets, and it can contribute to reduce coronary heart disease.

Association between DNA ploidy and micronucleus frequency in chronic smokers and impact of smoking cessation.

Tobacco use may initiate the process of oral carcinogenesis with clinically undetectable changes. Smoking cessation may prevent its progression. The objective of this study was to evaluate the association between DNA ploidy and micronucleus (MN) frequency in chronic smokers. Three groups were evaluated: Smoker Group, Former Smoker Group and Control Group. Exfoliative cytology was performed on the lateral border of the tongue and mouth floor. MN and DNA ploidy analyses were performed, as well as the correlation between the variables. The data showed a difference between the groups for the total MN (p = 0.0227), and the Smoker group had the highest mean (4.22 ± 4.12). The three groups did not differ statistically from each other on ploidy evaluation (p-value > 0.05). There was also an association between aneuploidy and increased MN frequency in the Former Smoker group (p = 0.0036). In conclusion, these results point out that there is a relationship between the frequency of MN and aneuploidy in former smokers. Moreover, smoking cessation, even for a short period of time, may promote the decrease of MN frequency caused by tobacco use.

Diagnóstico molecular de SARS-CoV-2 / Molecular diagnosis of SARS-CoV-2

Resumen El diagnóstico de COVID-19 se basa tanto en aspectos clínicos como en pruebas de detección, pero los síntomas y signos clínicos de los pacientes infectados son altamente atípicos y, por lo tanto, las pruebas moleculares son indispensables para su diagnóstico. La reacción en cadena de la polimerasa con transcriptasa inversa (RT-qPCR) se lleva a cabo en laboratorios nivel BSL II; asimismo, los principales blancos moleculares para la detección viral son el gen E (envoltura), y el gen RdRP (ARN polimerasa dependiente de ARN). Los falsos negativos en este diagnóstico se deben a la calidad y cantidad de la muestra, condiciones de transporte, almacenamiento, y manejo de estas antes y después de la extracción (el ARN es termolábil y abundantes las RNasas), fase de la infección, mutaciones del virus y presencia de inhibidores de la PCR. En estos casos, se recomienda una nueva toma de muestra, especialmente de vías respiratorias bajas, para aumentar la carga viral. Se debe tener en cuenta la sensibilidad analítica de la RT-qPCR (5,2 copias de ARN/reacción) y que, una vez el RNA se extrae, se va degradando progresivamente afectando la sensibilidad diagnóstica de la prueba. Un diagnóstico oportuno permite optimizar el manejo (aislamiento y tratamiento) y monitorización de los pacientes, así como la aplicación de medidas de prevención y control de la expansión, y la vigilancia epidemiológica de la enfermedad.

ABSTRACT COVID-19 diagnosis is based on both clinical aspects and screening tests. However, clinical symptoms and signs in infected patients are highly atypical; hence, molecular tests are essential for diagnosis. RT-qPCR is carried out at BSL II level laboratories; the main molecular targets for viral detection are E gene (envelope), and RdRP gene (RNA-dependent RNA polymerase). False negatives in this diagnosis are due to sample quality and quantity, transport conditions, storage and handling before and after extraction (RNA is heat-labile and RNases are abundant); infection phase; virus mutations and presence of CRP inhibitors. Taking into account analytical sensitivity of RT-qPCR (5.2 copies of RNA / reaction) and the fact that once RNA it is extracted, it progressively degrades and affects test diagnostic sensitivity, a new sample -specifically taken from the lower respiratory tract in order to increase viral load- is recommended in the abovementioned cases. Timely diagnosis allows optimizing management (isolation and treatment), patient monitoring, implementing prevention and control measures as well as epidemiological surveillance of the disease.

Differences in clinical manifestations and increased severity of systemic lupus erythematosus between two groups of Hispanics: European Caucasians versus Latin American mestizos (data from the RELESSER registry).

BACKGROUND: Systemic lupus erythematosus (SLE) is regarded as a prototype autoimmune disease because it can serve as a means for studying differences between ethnic minorities and sex. Traditionally, all Hispanics have been bracketed within the same ethnic group, but there are differences between Hispanics from Spain and those from Latin America, not to mention other Spanish-speaking populations. OBJECTIVES: This study aimed to determine the demographic and clinical characteristics, severity, activity, damage, mortality and co-morbidity of SLE in Hispanics belonging to the two ethnic groups resident in Spain, and to identify any differences. METHODS: This was an observational, multi-centre, retrospective study. The demographic and clinical variables of patients with SLE from 45 rheumatology units were collected. The study was conducted in accordance with Good Clinical Practice guidelines. Hispanic patients from the registry were divided into two groups: Spaniards or European Caucasians (EC) and Latin American mestizos (LAM). Comparative univariate and multivariate statistical analyses were carried out. RESULTS: A total of 3490 SLE patients were included, 90% of whom were female; 3305 (92%) EC and 185 (5%) LAM. LAM patients experienced their first lupus symptoms four years earlier than EC patients and were diagnosed and included in the registry younger, and their SLE was of a shorter duration. The time in months from the first SLE symptoms to diagnosis was longer in EC patients, as were the follow-up periods. LAM patients exhibited higher prevalence rates of myositis, haemolytic anaemia and nephritis, but there were no differences in histological type or serositis. Anti-Sm, anti-Ro and anti-RNP antibodies were more frequently found in LAM patients. LAM patients also had higher levels of disease activity, severity and hospital admissions. However, there were no differences in damage index, mortality or co-morbidity index. In the multivariate analysis, after adjusting for confounders, in several models the odds ratio (95% confidence interval) for a Katz severity index >3 in LAM patients was 1.45 (1.038-2.026; p = 0.02). This difference did not extend to activity levels (i.e. SLEDAI >3; 0.98 (0.30-1.66)). CONCLUSION: SLE in Hispanic EC patients showed clinical differences compared to Hispanic LAM patients. The latter more frequently suffered nephritis and higher severity indices. This study shows that where lupus is concerned, not all Hispanics are equal.

Evaluation of in ovo Bacillus spp. based probiotic administration on horizontal transmission of virulent Escherichia coli in neonatal broiler chickens.

This study evaluated the effect of in ovo Bacillus spp. base probiotic (BBP) administration on hatchability, Gram-negative bacteria (GNB) recovery, performance, and microbiota composition in 2 independent trials using a virulent E. coli seeder challenge model. In each trial, one hundred and eighty 18-day-old embryos were allocated into 1 of 2 groups: Control and treated group (inoculated with 107 BBP). On day 19 of embryogenesis, seeder embryos (n = 18) were inoculated with 4.5 × 104E. coli/mL+272 µg/mL tetracycline and segregated into mesh hatching bags. Twelve chicks per group were euthanized at hatch and at day 7 to evaluate the gastrointestinal composition of total GNB or total aerobic pasteurized bacteria. Also, in trial 2, ceca content from five chickens at day 7 were collected to evaluate microbiota composition. Embryos inoculated with BBP showed a significant (P < 0.05) reduction in the total number of GNB at day-of-hatch (DOH) and day 7. Probiotic treatment increased BW at DOH and day 7, and BW gain (days 0 to 7) when compared with Control chickens. Proteobacteria phylum was significantly reduced, while the Firmicutes was significantly increased by the BBP as compared to the Control (P < 0.05). At family level, Enterobacteriaceae was significantly decreased, while the Lachnospiraceae was significantly elevated in the BBP as compared to the Control group (P < 0.05). The genus Oscillospira was significantly enriched in the BBP group, whereas the unidentified genus of family Enterobacteriaceae in the Control group (P < 0.05). The BBP group increased the bacterial species richness, although there was no significant difference between treatments (P > 0.05). Interestingly, beta diversity showed a significant difference in bacterial community structure between Control and BBP groups (P < 0.05). The results of the present study suggest that in ovo administration of a BBP can reduce the severity of virulent E. coli horizontal transmission and infection of broiler chickens during hatch. The reduction in the severity of the transmission and infection by the BPP might be achieved through alterations of microbiota composition and its community structure.

Does fitness attenuate the relationship between changes in sitting time and health-related quality of life over time in community-dwelling older adults? Evidence from the EXERNET multicenter longitudinal study.

OBJECTIVE: To assess the relationship between fitness levels and components, sitting time and health-related quality of life (HRQoL), over time among community-dwelling older adults. METHODS: Three different sitting trajectories were calculated: (i) no change; (ii) decrease; and (iii) increase in ST, between baseline and follow-up. Fitness was assessed using the aerobic capacity, upper and lower limb strength, and total fitness. Participants were classified into higher (75th percentile or above) or lower (below 75th percentile) fitness levels, using the fitness tests. HRQoL scores at follow-up were compared to the three different sitting time trajectories within and across both the higher and the lower fitness groups for each of the three fitness indexes. RESULTS: Greater HRQoL scores were observed in those participants that decreased their ST as compared with those increasing their sitting time over time for participants classified in the lower end of their aerobic capacity or total fitness index. No differences were detected in HRQoL scores in people classified in the higher fitness level group for any of the fitness indexes. Participants that increased or did not change their sitting time and who were classified in the higher fitness end of aerobic capacity and total fitness index self-reported higher HRQoL scores when compared with those in the lower fitness end. CONCLUSION: Increased sitting time over time is associated with poorer HRQoL in older adults. Higher fitness levels could help attenuate the negative impact of sitting over time.

Socio-Ecological Factors Associated with Dengue Risk and Aedes aegypti Presence in the Galápagos Islands, Ecuador.

Dengue fever is an emerging infectious disease in the Galápagos Islands of Ecuador, with the first cases reported in 2002 and subsequent periodic outbreaks. We report results of a 2014 pilot study conducted in Puerto Ayora (PA) on Santa Cruz Island, and Puerto Baquerizo Moreno (PB) on San Cristobal Island. To assess the socio-ecological risk factors associated with dengue and mosquito vector presence at the household level, we conducted 100 household surveys (50 on each island) in neighborhoods with prior reported dengue cases. Adult mosquitoes were collected inside and outside the home, larval indices were determined through container surveys, and heads of households were interviewed to determine demographics, self-reported prior dengue infections, housing conditions, and knowledge, attitudes, and practices regarding dengue. Multi-model selection methods were used to derive best-fit generalized linear regression models of prior dengue infection, and Aedes aegypti presence. We found that 24% of PB and 14% of PA respondents self-reported a prior dengue infection, and more PB homes than PA homes had Ae. aegypti. The top-ranked model for prior dengue infection included several factors related to human movement, household demographics, access to water quality issues, and dengue awareness. The top-ranked model for Ae. aegypti presence included housing conditions, mosquito control practices, and dengue risk perception. This is the first study of dengue risk and Ae. aegypti presence in the Galápagos Islands.