No abstract

Human papillomavirus (HPV) is the primary infectious agent for the development of cervical cancer, although the presence of the virus alone is insufficient for viral development and proliferation; this can be attributed to the increase in potential oncogenic risk, along with other risk factors. In the present investigation, the prevalence of high-risk HPV was determined from samples of premalignant or malignant cervical cytology in women from the southern region of Ecuador. The kit we used was able to detect genotypes 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 59. In addition, 64.5% of the analyzed samples were positive for HPV, with genotypes 16 and 18 being the most prevalent (16 was detected in 148 samples and 18 in 108). Genotypes 58 and 51 were the third most frequent simple and multiple infections, respectively. The data are very similar to those obtained worldwide, suggesting that the strategy of sex education, and the use of vaccines as primary prevention agents, could significantly decrease the incidence and mortality rate of cervical cancer in the southern region of Ecuador.

The potential risk of pesticide exposure in developing countries needs further study as data are limited and simple tools to assess the risks on human health and the environment caused by pesticides are lacking. This article introduces a potential pesticides exposure index (PPEI) as a modeling tool to assess the risk of human and environmental pesticide exposure in agricultural basins. The PPEI is based on a number of factors including: human population centers and their proximity to agricultural crops, the toxicological properties of pesticides, and their application frequency. The index was applied to a region in southern Ecuador (approximately 7200 km 2 ) where corn, rice, and sugarcane are the predominant crops, and where hot spots with the highest vulnerability to pesticide residues were identified. Of the total of 5326 neighborhoods for the entire study area, 1030 had high, 1124 had medium, and 1009 had low PPEI scores. Among the practical uses of PPEI are to help to assist regulatory agencies and academics evaluate the effects of land use policies on pesticide vulnerability. Also, it can be easily expanded to include other parameters, such as data from other agricultural crops, or frequency of pesticide application. The PPEI can be a valuable indicator of risk of pesticide exposure, as it is reliable and applicable to developing countries, where data and resources are limited.

Background: contamination of aquatic ecosystems by oil spills associated with petroleum exploitation represents a serious problem of environmental contamination that can affect human health. We developed a spatial model of contamination risk in the Ecuadorian Amazon, and evaluated the model using independent datasets on environmental contamination and clinical indicators of human health risk factors. Methods: the spatial risk of contamination for the Napo River basin was based on the calculation of a friction surface and the accessibility of possible oil contamination. Human health was evaluated using peripheral blood samples from 256 individuals. We used monitoring data on contamination to validate the spatial model of contamination risk and analyzed whether the estimated risk explained the incidence of human health risk factors. Results: our risk model showed a significant association with actual contamination detected in the study area. According to our risk model, around 30% of the territory has some level of contamination. Risk of contamination was associated with an increasing mean incidence in risk factors for human health in resident populations, but elevated contamination risk was not a significant predictor of the incidence of selected health indicators; only the incidence of inflammation was significantly increased. Conclusions: a large proportion of the populations in the Napo River basin has high vulnerability to contamination from petroleum exploitation, and this contamination risk may be traced in some indicators of health risk. Closer examination of health risk factors is warranted, and our spatial model of contamination risk can inform the design and analysis of such studies, as well as risk mitigation and management. Our approach to building the model of contamination risk could be applied in other catchments where petroleum exploitation is contemplated.