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Abstract Background Plasmodium vivax and Plasmodium falciparum cause a significant illness burden in Peru. Anopheline indices for populated communities in the peri-Iquitos region of Loreto have been reported to be remarkably low, with entomological inoculation rates (EIR) estimated at one to 30 infective bites per year based on a few studies in close proximity to the urban centre of Iquitos and surrounding deforested areas. Local reports suggest that a large number of the reported cases are contracted outside of populated communities in undeveloped riverine areas frequented by loggers and fishermen. Methods To better understand vectorial capacity in suspected high malaria transmission zones in a rural district near Iquitos, Peru, mosquito collections were conducted at different points in the seasonality of malaria transmission in 21 sites frequented by occupational labourers. Prevalence of Plasmodium spp in vectors was determined by circumsporozoite protein ELISA on individual mosquitoes. Slide surveillance was performed for humans encountered in the zone. Results In total, of 8,365 adult female mosquitoes examined, 98.5% were identified as Anopheles darlingi and 117 (1.4%) tested positive for sporozoites (P. falciparum, P. vivax VK210 or P. vivax VK247). Measured human biting rates at these sites ranged from 0.102 to 41.13 bites per person per hour, with EIR values as high as 5.3 infective bites per person per night. Six percent of the 284 blood films were positive for P. vivax or P. falciparum; however, 88% of the individuals found to be positive were asymptomatic at the time of sampling. Conclusions The results of this study provide key missing indices of prominent spatial and temporal heterogeneity of vectorial capacity in the Amazon Basin of Peru. The identification of a target human subpopulation as a principal reservoir and dispersion source of Plasmodium species has important implications for vaccine development and the delivery of effective targeted malaria control strategies.

Objective: To examine the relationship between measures of sleep quality and cognitive performance in HIV-positive individuals stable on combination antiretroviral therapy., Design: Multimethod assessments of sleep quality, patterns, and cognitive performance were assessed in a predominantly black HIV-positive cohort., Methods: Sleep quality and patterns were characterized in 36 subjects by polysomnogram, 2-week actigraphy monitoring, and validated sleep questionnaires. Cognitive performance was assessed with a battery of neuropsychological tests., Results: The majority of participants were cognitively impaired [based on Frascati (75%) criteria]. Self-reported mean scores on the Pittsburgh sleep quality index and the insomnia severity scale suggested poor sleep quality. Better cognitive performance, particularly on tasks of attention, frontal/executive function, and psychomotor/motor speed, was associated with polysomnogram sleep indices (ie, reduced wake after sleep onset, greater sleep efficiency, greater sleep latency, and greater total sleep time). Thirty-seven percent of participants had sleep patterns suggestive of chronic partial sleep deprivation, which was associated with significantly worse performance on the digit symbol test (P = 0.006), nondominant pegboard (P = 0.043), and verbal fluency tests (P = 0.044)., Conclusions: Our results suggest that compromised sleep quality and duration may have a significant impact on cognitive performance in HIV-positive individuals. Future studies are warranted to determine the utility of sleep quality and quantity indices as potential predictive biomarkers for development and progression of future HIV-associated neurocognitive disorder.