Association of dengue fever with Aedes spp. abundance and climatological effects.

OBJECTIVE: To analyze the association of dengue fever incidence with Aedes mosquito's abundance, and the effect of climatological and geographical variables, in a region in Morelos State, Mexico. MATERIALS AND METHODS: Weekly data during the period 2010 to 2014 was used. Mosquito abundance was determined using ovitraps. Confirmed dengue cases were obtained from the Epidemiological Surveillance System. Climatic variables were obtained from weather monitoringstations. The correlation between climate variables and ovitraps data was estimated using a multivariate regression model. RESULTS: A correlation of mosquito abundance with dengue fever incidence, and a yearly pattern with seasonal variations were observed. The daily mean temperature, relative humidity and rainfall parameters were associated with mosquito egg abundance. Time lags of three and four weeks between egg counts and dengue fever incidence were observed. CONCLUSION: Time lags between egg counts and dengue incidence could be useful for prevention and control interventions.

First Report of Seropositivity to Trypanosoma cruzi in Mexican Afro-Descendants from Guerrero and Oaxaca States.

Mexican Afro-descendant is a population poorly studied in many aspects, between them the infectious diseases that they suffer. This population is mainly found in the country's Pacific (Oaxaca and Guerrero states) and Atlantic (Veracruz) coast. In these regions, a diversity of triatomine vectors of the Chagas disease is found. Also, all the genotypes of Trypanosoma cruzi DTUs have been reported. That is why the present study aimed to study the presence of antibodies against T. cruzi and cardiac pathology associated with the Chagas disease in the Mexican Afro-descendant population of Guerrero and Oaxaca. ELISA, Western blot, and recombinant antigen's ELISA were used to evaluate the seropositivity of these communities. Furthermore, an electrocardiographic study and evaluation of risk factors associated with T. cruzi infection in the Oaxaca and Guerrero populations were conducted. 26.77% of the analyzed population was positive for two serological tests. These percentages are higher than the previously reported for the mestizo population in similar studies. Electrocardiographic results showed cardiac disorder associated with the Chagas disease in the population. Also, risk factors were identified associated with the men's activities in the outdoor working areas.

Environmental Health Promotion of a Contaminated Site in Mexico.

Entangled in complex ecological, sociocultural, and economic systems, current environmental health problems require integrated participatory approaches. Alpuyeca, a semi-urban, highly marginalized community in South-Central Mexico burdened by lead and polychlorinated biphenyl (PCB) contamination, dengue fever, and intestinal diseases, illustrates this. Its residents are distinctive, however, for their concerted actions in the face of environmental problems and the presence of defenders of a prehispanic worldview based on the protection of nature. This article addresses the health impacts of an integrated environmental health promotion strategy implemented through a participatory action research intervention based on qualitative and quantitative methods. Different actors, sectors, dimensions, and knowledge types were harmonized in a collaborative space created specifically for our interdisciplinary research team, community residents and local authorities. Reflections, plans and actions were developed collectively in this space with the view of finding solutions anchored in the local culture. Results included sharp reductions in blood-lead concentrations among children, in entomological indices, and in PCB contamination, as well as capacity strengthening. Medium-level community participation was achieved. This work contributes evidence that participatory environmental health research can be effective in analyzing and reducing problems in communities with multiple environmental health concerns. It complements ecohealth and environmental health literacy approaches.

Association of dengue fever with Aedes spp. abundance and climatological effects / Asociación de casos de dengue con variación en la abundancia de Aedes y clima

Abstract: Objective: To analyze the association of dengue fever incidence with Aedes mosquito's abundance, and the effect of climatological and geographical variables, in a region in Morelos State, Mexico. Materials and methods: Weekly data during the period 2010 to 2014 was used. Mosquito abundance was determined using ovitraps. Confirmed dengue cases were obtained from the Epidemiological Surveillance System. Climatic variables were obtained from weather monitoring stations. The correlation between climate variables and ovitraps data was estimated using a multivariate regression model. Results: A correlation of mosquito abundance with dengue fever incidence, and a yearly pattern with seasonal variations were observed. The daily mean temperature, relative humidity and rainfall parameters were associated with mosquito egg abundance. Time lags of three and four weeks between egg counts and dengue fever incidence were observed. Conclusion: Time lags between egg counts and dengue incidence could be useful for prevention and control interventions.

Resumen: Objetivo: Analizar la asociación de la incidencia de dengue con la abundancia de mosquitos Aedes y el efecto de variables climatológicas, en una región de Morelos, México. Material y métodos: Se utilizaron datos semanales durante el 2010-2014. La abundancia de mosquitos se determinó utilizando ovitraps. Los casos de dengue se obtuvieron del Sistema de Vigilancia Epidemiológica. Las variables climáticas se obtuvieron de estaciones climatológicas locales. La correlación entre las variables climáticas y los datos de ovitrampas se estimó mediante un modelo de regresión multivariado. Resultados: Se observó una correlación de la abundancia de mosquitos con la incidencia de dengue. La temperatura media diaria, humedad relativa y la precipitación pluvial se asociaron con abundancia de mosquitos. Se observó un desfase temporal de tres a cuatro semanas entre cuentas de huevos y la incidencia de dengue. Conclusión: Los intervalos entre las cuentas de huevos y la incidencia de dengue podrían ser utilizados para planear intervenciones de prevención y control.

HLA class I and II polymorphisms in Mexican Mestizo patients with dengue fever.

Host genetics in dengue hemorrhagic fever (DHF) pathophysiology has not been extensively investigated. Most studies have focused on HLA in different populations; however these reported associations have not been replicated. We performed a case-control study to analyze possible associations of HLA-A, HLA-B, HLA-Cw, HLA-DRB1 and HLA-DQB1 alleles with clinical disease severity caused by dengue virus infection. Our population consisted of 39 individuals (DF: 23, DHF: 16) and 34 healthy controls from the State of Morelos, Mexico. HLA loci were genotyped by nucleotide sequencing method. Statistical analyses revealed associations in three alleles: HLA-B*35 was negatively associated with symptomatic disease (p<1x10(-4), p(c)=0.01, OR=0.12, 95%CI=0.037-0.39), and DF (p=0.0007, p(c)=0.03, OR=0.13, 95%CI=0.031-0.51). HLA-DQB1*0302 was positively associated with DHF (p=0.018, p(c)=NS, OR=5.02, 95%CI=1.05-25.34), and negatively with DF (p=0.011, p(c)=NS, OR=0.23, 95%CI=0.06-0.84). HLA-DQB1*0202 was positively associated with DF only (p=0.012, p(c)=NS, OR=7.0, 95%CI=1.11-73.8). We identified possible associations of HLA-B and HLA-DQB1 alleles with the risk of developing symptomatic disease, DF and DHF in a Mexican Mestizo population.

Colonización bacteriana nasofaríngea en niños que asisten a guardería y niños cuidados en casa / Nasopharyngeal bacterial colonization in children attending a day care center and children

Se realizó un estudio de casos y controles para determinar las diferencias de colonización nasofaríngea de niños sanos que asisten a una guardería y niños cuidados en casa. Cuatro bacterias: heamophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis y Streptococcus pyogenes, fueron seleccionadas. Se utilizó la razón de momios (RM) para precisar su asociación y analizar ambos grupos. Se evidenció colonización nasofarñingea en 87 de 127 niños de guardería contra 43 de 127 niños cuidados en casa una Rm de 4.25, p (95 por ciento)<0.05. Individualmente la RM para S. pneumoniae, H. influenzae y M. catarrhalis, fue de 3.12, 2.65 y 1.7, respectivamente. La frecuencia para S. pyogenes fue baja. Se compararan las cifras encontradas en este estudio con prevalencias previas reportadas. Se plantea que la asistencia a una guardería, dado el incremento en la colonozación nasofaríngea observada, posiblemente sea un factor de riesgo para una mayor frecuencia de infección respiratoria y/o enfermedad invarora, causada por este tipo de bacterias