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Infectious diseases transmitted by ectoparasites such as fleas, lice, mites, and ticks constitute a global public health problem. Tick-borne diseases are the most widely studied emerging ectoparasite-borne diseases (EBD) mainly due to their increasing incidence worldwide, including in South America. Furthermore, in Peru and neighboring Andean countries (Bolivia, Colombia, and Ecuador), surveillance reports indicate that Rickettsia species appear to be the most diverse and widely distributed ectoparasite-borne pathogens (EBP) followed by Babesia species, and with fewer species of Anaplasma, Bartonella, Borrelia, Ehrlichia, Coxiella, and Phlebovirus pathogens. Amblyomma, Dermacentor, Rhipicephalus, and Ixodes ticks were reported as the most predominant ectoparasites found infected with a diversity of EBP belonging to Rickettsia, Babesia, Anaplasma, Bartonella, and Ehrlichia species. Overall, people living in rural areas where agriculture and livestock production are their main economic means are at higher risk of EBD., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (Published by Oxford University Press on behalf of Infectious Diseases Society of America 2025.)

Dengue is the most widespread vector-borne viral infection globally and a serious public health problem. The 2023-2024 dengue outbreak across Latin America has drastically impacted Peru, including previously unaffected areas such as metropolitan Lima and Amazonian rural communities, presumably due to climate change. Research studies conducted in Iquitos, the largest city in the Peruvian Amazon, showed that ultra-low-volume pyrethroid spray applications against the dengue vector Aedes aegypti were effective when adequate coverage and quality control were carried out. Insecticide-treated curtains were not effective at controlling dengue transmission in Iquitos, whereas the use of passive spatial repellent emanators demonstrated 34% protective efficacy against Aedes-borne virus infection. In modeling studies, targeted indoor residual spray strategies showed promising reductions in dengue transmission, which require empirical evaluation. Trials conducted in Iquitos have shown that larval control alone is not sufficient to control Ae. aegypti, urging that government programs must consider integrated vector management., Competing Interests: Potential conflicts of interest. The authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (Published by Oxford University Press on behalf of Infectious Diseases Society of America 2025.)

The present study aimed to evaluate the cross-cultural measurement invariance of the Pandemic Grief Scale (PGS) in ten Latin American countries. A total of 2,321 people who had lost a family member or other loved one due to COVID-19 participated, with a mean age of 34.22 years old (SD = 11.99). In addition to the PGS, a single item of suicidal ideation was applied. The unidimensional model of the PGS had adequate fit in most countries and good reliability estimates. There was evidence of measurement invariance by country and gender. Also, a one-point increase in the PGS was associated with an almost twofold increase in the odds of suicidal ideation. Scores greater than or equal to 4 on the PGS are proposed as a cut off to identify individuals with suicidal ideation. Strong evidence of the cross-cultural validity of the PGS is provided., Competing Interests: Author’s NoteMiguel Gallegos is now affiliated with Departamento de Psicología. Universidad Católica del Maule, Talca, Chile and Programa de Posgrado en Psicología. Pontificia Universidade Católica de Minas Gerais, Minas Gerais, Brasil. Ilka Franco Ferrari is now affiliated with Programa de Posgrado en Psicología. Pontificia Universidade Católica de Minas Gerais, Minas Gerais, Brasil. Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: There is an urgent need to assess changes in well-being on a multinational scale during the COVID-19 pandemic, thus culturally valid scales must be available., Methods: With this in mind, this study examined the invariance of the WHO well-being index (WHO-5) among a sample of 5183 people from 12 Latin Americans countries (Argentina, Bolivia, Chile, Colombia, Cuba, Ecuador, El Salvador, Guatemala, Mexico, Paraguay, Peru, and Uruguay)., Results: The results of the present study indicate that the WHO-5 is strictly invariant across samples from different Latin American countries. Furthermore, the results of the IRT analysis indicate that all items of the WHO-5 were highly discriminative and that the difficulty required to respond to each of the five items is ascending. Additionally, the results indicated the presence of moderate and small size differences in subjective well-being among most countries., Conclusion: The WHO-5 is useful for assessing subjective well-being in 12 Latin American countries during the COVID-19 pandemic, since the differences between scores can be attributed to differences in well-being and not in other characteristics of the scale., (© 2023. The Author(s).)

The Anopheles subgenus Kerteszia is a poorly understood group of mosquitoes that includes several species of medical importance. Although there are currently twelve recognized species in the subgenus, previous studies have shown that this is likely to be an underestimate of species diversity. Here, we undertake a baseline study of species delimitation using the barcode region of the mtDNA COI gene to explore species diversity among a geographically and taxonomically diverse range of Kerteszia specimens. Beginning with 10 of 12 morphologically identified Kerteszia species spanning eight countries, species delimitation analyses indicated a high degree of cryptic diversity. Overall, our analyses found support for at least 28 species clusters within the subgenus Kerteszia . The most diverse taxon was Anopheles neivai , a known malaria vector, with eight species clusters. Five other species taxa showed strong signatures of species complex structure, among them Anopheles bellator , which is also considered a malaria vector. There was some evidence for species structure within An. homunculus , although the results were equivocal across delimitation analyses. The current study, therefore, suggests that species diversity within the subgenus Kerteszia has been grossly underestimated. Further work will be required to build on this molecular characterization of species diversity and will rely on genomic level approaches and additional morphological data to test these species hypotheses.

U.S. military troops are exposed to mosquito-borne pathogens when deployed to endemic regions. Personal protective measures such as permethrin-treated uniforms and dermal repellents are the cornerstones of mosquito-borne disease prevention for the U.S. military. These measures have limitations and additional personal protection tools, such as spatial repellent devices to decrease the risk of vector-borne pathogen transmission, are required. Novel spatial repellent controlled-release devices formulated with metofluthrin were evaluated in an outdoor setting in the northern Amazon of Peru to evaluate performance under field conditions. The metofluthrin emitting devices lowered the number of mosquitoes captured in protected human landing collections (HLC) compared to blank devices, although there were effect differences between Anopheles spp. and species in other mosquito genera. A computational-experimental model was developed to correlate HLC and active ingredient (AI) concentrations as a function of time and space. Results show a strong correlation between the released AI and the decrease in HLC. This model represents the first effort to obtain a predictive analytical tool on device performance using HLC as the entomological endpoint.

Despite several reports worldwide documenting the presence of Rickettsia asembonensis in samples derived from ectoparasites, animals and more recently humans, genomic information of these specimens remains scarce, and when available, is usually limited to small genomic fragments of limited value. We generated complete sequences for two conserved (17-kDa antigen gene and gltA ) and three variable ( sca4 , ompB and ompA ) genes in five R. asembonensis DNA samples detected in cat and dog fleas in Peru. Complete gene sequences were used to conduct multi-locus sequence typing and phylogenetic analyses to assess diversity and infer relationships among strains and other reference sequences. The 17-kDa antigen gene was highly conserved across Rickettsia species. Of the variable genes ompB was the most variable, but this diversity was not captured through phylogenetics alone even when efforts were made to maximize potential diversity in terms of flea species, animal host and location. Through a combination of de novo and reference-based genome assembly we identified a 75 bp insertion in ompA that encodes a 25 aa repetitive motif found in other Rickettsia species, but not present in the original prototype strain from Kenya. R. asembonensis has only recently been shown to be a bona-fide human pathogen. As such, and compounded by a lack of available genomic information, it remains understudied. Our work directly addresses the lack of genomic information available worldwide for the study of these novel Rickettsia species and specifically contributes to our understanding of the diversity and molecular epidemiology of R. asembonensis in Peru.

The Coronavirus Anxiety Scale (CAS) was recently developed to assess dysfunctional anxiety related to COVID-19. Although different studies reported that the CAS is psychometrically sound, it is unclear whether it is invariant across countries. Therefore, the present study aimed to examine the measurement invariance of the CAS in twelve Latin American countries (Argentina, Bolivia, Chile, Colombia, Cuba, Ecuador, El Salvador, Guatemala, Mexico, Paraguay, Peru, and Uruguay). A total of 5196 people participated, with a mean age of 34.06 (SD = 26.54). Multigroup confirmatory factor analysis (CFA) was used to examine the measurement invariance of the CAS across countries and gender. Additionally, the graded response model (GRM) was used to provide a global representation of the representativeness of the scale with respect to the COVID-19 dysfunctional anxiety construct. The unidimensional structure of the five-item CAS was not confirmed in all countries. Therefore, it was suggested that a four-item model of the CAS (CAS-4) provides a better fit across the twelve countries and reliable scores. Multigroup CFA showed that the CAS-4 exhibits scalar invariance across all twelve countries and all genders. In addition, the CAS-4 items are more informative at average and high levels of COVID-19 dysfunctional anxiety than at lower levels. According to the results, the CAS-4 is an instrument with strong cross-cultural validity and is suitable for cross-cultural comparisons of COVID-19 dysfunctional anxiety symptoms in the general population of the twelve Latin American countries evaluated., Supplementary Information: The online version contains supplementary material available at 10.1007/s12144-021-02563-0., Competing Interests: Competing InterestNone, (© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2021.)

The invariance of the Preventive COVID-19 Infection Behaviors Scale (PCIBS) was evaluated in 12 Latin American countries (Argentina, Bolivia, Chile, Colombia, Cuba, Ecuador, El Salvador, Guatemala, Mexico, Paraguay, Peru, and Uruguay). A total of 5183 people from the aforementioned countries participated, selected using the snowball sampling method. Measurement invariance was assessed by multigroup confirmatory factor analysis (MG-CFA) and Multi-Group Factor Analysis Alignment (CFA-MIAL). In addition, item characteristics were assessed based on Item Response Theory. The results indicate that the original five-item version of the PCIBS is not adequate; whereas a four-item version of the PCIBS (PCIBS-4) showed a good fit in all countries. Thus, using the MG-CFA method, the PCIBS-4 achieved metric invariance, while the CFA-MIAL method indicated that the PCIBS-4 shows metric and scalar invariance. Likewise, the four items present increasing difficulties and high values in the discrimination parameters. The comparison of means of the PCIBS-4 reported irrelevant differences between countries; however, Mexico and Peru presented the highest frequency of preventive behaviors related to COVID-19. It is concluded that the PCIBS-4 is a unidimensional self-report measure which is reliable and invariant across the twelve participating Latin American countries. It is expected that the findings will be of interest to social and health scientists, as well as those professionals directly involved in public health decision making., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Caycho-Rodríguez, Vilca, Valencia, Carbajal-León, Vivanco-Vidal, Saroli-Araníbar, Reyes-Bossio, White, Rojas-Jara, Polanco-Carrasco, Gallegos, Cervigni, Martino, Palacios, Moreta-Herrera, Samaniego-Pinho, Lobos-Rivera, Ferrari, Flores-Mendoza, Figares, Puerta-Cortés, Corrales-Reyes, Calderón, Tapia and Gallegos.)

Rickettsiae and bartonellae are Gram-negative bacteria that can cause zoonotic and human diseases and are vectored by hematophagous arthropods. In the Americas, rickettsioses and bartonelloses have reemerged as significant public health threats. Bartonella species have been identified as causing zoonotic infections responsible for a variety of clinical syndromes in humans and animals. The aim of this study was to investigate the distribution, prevalence, and molecular heterogeneity of Rickettsia spp. and Bartonella spp. among ectoparasites collected from domestic animals in 14 farming communities in the Andes Mountains of Cuzco, Peru. A total of 222 domestic animals representing 8 different species (sheep, donkeys, goats, cattle, pigs, llamas, guinea pigs, and horses) were sampled. Nine species of ectoparasites ( n  = 1,697) collected from 122 animals were identified resulting in 1,657 chewing lice, 39 ticks, and 1 flea. DNA was individually extracted from a random sample of 600 (35.4%) considering variability of ectoparasite species, hosts, and sample location elevation. All 600 samples were negative for rickettsial DNA by a genus-specific molecular assay. A subset of 173 (28.8%) samples were selected based on variability of arthropods species, host, and location for Bartonella testing. Ninety-one (52.6%) of these samples including Melophagus ovinus (90/110) and Bovicola bovis (1/7) were positive for Bartonella by a genus-specific molecular assay. Five Bartonella genes of seven DNA samples from M. ovinus were analyzed by the multilocus sequence typing for characterization. We identified five identical Bartonella melophagi specimens and two specimens with Bartonella species related to B. melophagi from the seven M. ovinus. The Bartonella agents detected were widely distributed and frequent in multiple studied locations.

Rickettsia and Leptospira spp. are under-recognized causes of acute febrile disease worldwide. Rickettsia species are often placed into the spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR). We explored the antibody prevalence among humans for these two groups of rickettsiae in four regions of Peru (Lima, Cusco, Puerto Maldonado, and Tumbes) and for Leptospira spp. in Puerto Maldonado and Tumbes. We also assessed risk factors for seropositivity and collected serum samples and ectoparasites from peri-domestic animals from households in sites with high human seroprevalence. In total, we tested 2,165 human sera for antibodies (IgG) against SFGR and TGR by ELISA and for antibodies against Leptospira by a microscopic agglutination test. Overall, human antibody prevalence across the four sites was 10.6% for SFGR (ranging from 6.2% to 14.0%, highest in Tumbes) and 3.3% for TGR (ranging from 2.6% to 6.4%, highest in Puerto Maldonado). Factors associated with seroreactivity against SFGR were male gender, older age, contact with backyard birds, and working in agriculture or with livestock. However, exposure to any kind of animal within the household decreased the odds ratio by half. Age was the only variable associated with higher TGR seroprevalence. The prevalence of Leptospira was 11.3% in Puerto Maldonado and 5.8% in Tumbes, with a borderline association with keeping animals in the household. We tested animal sera for Leptospira and conducted polymerase chain reaction (PCR) to detect Rickettsia species among ectoparasites collected from domestic animals in 63 households of seropositive participants and controls. We did not find any association between animal infection and human serostatus.

Here we analyze the simultaneous relationships among five variables. Two refer to childhood (episodes of various forms of maltreatment and externalizing behaviors), whereas three refer to early adulthood (intelligence, personality, and socialization difficulties). The 120 individuals considered for the present report were invited from the 650 schoolchildren participating in the Longitudinal Study of Intelligence and Personality (Minas Gerais, Brazil). The complete sample was recruited in 2002 (T1; mean age = 10.0; standard deviation (SD) = 2.2) and 120 were tested again in 2014-17 (T2; mean age = 23.5; SD = 2.2). Externalizing behaviors were registered at T1, whereas the remaining variables were obtained at T2. These were the main results: (1) externalizing behaviors predict future social effectiveness (as estimated by the general factor of personality derived from the NEO Personality Inventory-Revised (NEO-PI-R) and socialization difficulties computed from the socialization scale (SOC)) and future intelligence performance (as assessed by a set of fluid and crystallized tests); (2) episodes of self-reported childhood maltreatment predict social effectiveness, but not intelligence; (3) maltreatment and externalizing behaviors are unrelated; and (4) social effectiveness (personality) and intelligence are unrelated. Therefore, the findings support the dissociation between adult intelligence and personality with respect to maltreatment episodes and externalizing behaviors occurring in childhood. Implications of these findings for social policies aimed at preventing adult socially ineffective personalities are underscored.

The purpose of this study was to determine the immediate effects of cognitive training on healthy older adults and verify the transfer effects of targeted and non-targeted abilities. The design consisted of a semi-randomized clinical controlled trial. The final sample was composed of 80 volunteers recruited from a Brazilian community (mean age = 69.69; SD = 7.44), which were separated into an intervention group (N = 47; mean age = 69.66, SD = 7.51) and a control group (N = 33; mean age = 69.73, SD = 7.45). Intervention was characterized by adaptive cognitive training with 12 individual training sessions of 60 to 90 minutes (once a week). Eight instruments were used to assess effects of cognitive training. Five were used to assess trained abilities (near effects), including: Memorization Tests (List and History), Picture Completion, Digit Span, Digit Symbol-Coding, and Symbol Search (the last four from WAIS-III). Two instruments assessed untrained abilities (far effects): Arithmetic and Matrix Reasoning (WAIS-III). The non-parametric repeated measures ANOVA test revealed a significant interaction between group by time interaction for Picture Completion [F(74) = 14.88, p = .0002, d = 0.90, CLES = 73.69%], Digit Symbol-Coding [F(74) = 5.66, p = .019, d = 0.55, CLES = 65.21%] and Digit Span [F(74) = 5.38, p = .02, d = 0.54, CLES = 64.85%], suggesting an interventional impact on these performance tasks. The results supported near transfer effects, but did not demonstrate a far transfer effects.

The transmission dynamics of many arboviruses in the Amazon Basin region have not been fully elucidated, including the vectors and natural reservoir hosts. Identification of blood meal sources in field-caught mosquitoes could yield information for identifying potential arbovirus vertebrate hosts. We identified blood meal sources in 131 mosquitoes collected from areas endemic for arboviruses in the Peruvian Department of Loreto by sequencing polymerase chain reaction amplicons of the cytochrome b gene. Psorophora (Janthinosoma) albigenu, Psorophora (Grabhamia) cingulata, Mansonia humeralis, Anopheles oswaldoi s.l., and Anopheles benarrochi s.l. had mainly anthropophilic feeding preferences; Aedes (Ochlerotatus) serratus, and Aedes (Ochlerotatus) fulvus had feeding preferences for peridomestic animals; and Culex (Melanoconion) spp. fed on a variety of vertebrates, mainly rodents (spiny rats), birds, and amphibians. On the basis of these feeding preferences, many mosquitoes could be considered as potential enzootic and bridge arbovirus vectors in the Amazon Basin of Peru., (© The American Society of Tropical Medicine and Hygiene.)

Using a large, passive, clinic-based surveillance program in Iquitos, Peru, we characterized the prevalence of rickettsial infections among undifferentiated febrile cases and obtained evidence of pathogen transmission in potential domestic reservoir contacts and their ectoparasites. Blood specimens from humans and animals were assayed for spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR) by ELISA and/or PCR; ectoparasites were screened by PCR. Logistic regression was used to determine associations between patient history, demographic characteristics of participants and symptoms, clinical findings and outcome of rickettsial infection. Of the 2,054 enrolled participants, almost 2% showed evidence of seroconversion or a 4-fold rise in antibody titers specific for rickettsiae between acute and convalescent blood samples. Of 190 fleas (Ctenocephalides felis) and 60 ticks (Rhipicephalus sanguineus) tested, 185 (97.4%) and 3 (5%), respectively, were positive for Rickettsia spp. Candidatus Rickettsia asemboensis was identified in 100% and 33% of the fleas and ticks tested, respectively. Collectively, our serologic data indicates that human pathogenic SFGR are present in the Peruvian Amazon and pose a significant risk of infection to individuals exposed to wild, domestic and peri-domestic animals and their ectoparasites.

Background: Anopheles darlingi is the main malaria vector in the Amazon region and is among the most efficient malaria vectors worldwide. However, due to the lack of a well-established laboratory colony, key control-relevant aspects of the bionomics, behaviour, genetics, and vector-parasite relationships of An. darlingi remain unknown. Here, biological parameters that had been successful in initiating other Anopheles colonies were optimized and improved for An. darlingi, with the aim of establish a free-mating, stable, and highly productive laboratory colony., Methods: Wild An. darlingi adult females were field collected from Zungarococha, Loreto Department, Peru (03°49'32.40″S, 73°21'00.08″W), and taken to the NAMRU-6 Insectary in Iquitos where F(1) offspring were produced and reared. Natural copulation was successfully induced in F1 adults under a thermoperiod of 30 ± 1 °C during the day and 25 ± 1 °C at night, and with a 30-min LED light stimulation period at dusk. Oviposition success was enhanced using egg-laying containers with a dark-coloured surface. Larval feeding regimes were standardized for optimal larval development. Optimized copulation induction methods were used to facilitate mating in An. darlingi until the F(10) generation. No copulation induction assistance was needed in subsequent generations., Results: In 19 generations, the An. darlingi colony produced a total of 763,775 eggs; 441,124 larvae; 248,041 pupae; and 231,591 adults. A mean of 0.56 sexual encounters/female/cage (n = 36 cages) was recorded across the first ten generations (F(1)-F(10)). A mean insemination rate of 54.7 % (n = 5,907 females) ranging from 43.6 % (F(2)) to 66.6 % (F(10)) was recorded across nine generations (F(2)-F(10)). Free-mating was casually observed in the F(8) generation, and subsequently confirmed in the F(9) and F(10) generations; comparable insemination rates and egg laying between stimulated (51.6 %, 12.9 eggs/female), and non-stimulated (52.3 %, 11.2 eggs/female) females were recorded. The time from egg to adult development ranged from 10 to 20 days. Moreover, the colony was relocated to a new laboratory within Iquitos in the F(14) generation without any noted changes in its productivity. By March 2015, the An. darlingi colony has been successfully reared to the F(26) generation., Conclusions: This constitutes the first report of a free-mating, highly productive, and long-standing An. darlingi laboratory colony established through natural copulation induction, which will support critical malaria research. This rearing methodology may be a transferable, cost-effective alternative to labour-intensive forced mating practices widely used in maintaining other Anopheles colonies.

Background: Effective malaria control relies on accurate identification of those Anopheles mosquitoes responsible for the transmission of Plasmodium parasites. Anopheles oswaldoi s.l. has been incriminated as a malaria vector in Colombia and some localities in Brazil, but not ubiquitously throughout its Neotropical range. This evidence together with variable morphological characters and genetic differences supports that An. oswaldoi s.l. compromises a species complex. The recent fully integrated redescription of An. oswaldoi s.s. provides a solid taxonomic foundation from which to molecularly determine other members of the complex., Methods: DNA sequences of the Second Internal Transcribed Spacer (ITS2 - rDNA) (n = 192) and the barcoding region of the Cytochrome Oxidase I gene (COI - mtDNA) (n = 110) were generated from 255 specimens of An. oswaldoi s.l. from 33 localities: Brazil (8 localities, including the lectotype series of An. oswaldoi), Ecuador (4), Colombia (17), Trinidad and Tobago (1), and Peru (3). COI sequences were analyzed employing the Kimura-two-parameter model (K2P), Bayesian analysis (MrBayes), Mixed Yule-Coalescent model (MYC, for delimitation of clusters) and TCS genealogies., Results: Separate and combined analysis of the COI and ITS2 data sets unequivocally supported four separate species: two previously determined (An. oswaldoi s.s. and An. oswaldoi B) and two newly designated species in the Oswaldoi Complex (An. oswaldoi A and An. sp. nr. konderi). The COI intra- and inter-specific genetic distances for the four taxa were non-overlapping, averaging 0.012 (0.007 to 0.020) and 0.052 (0.038 to 0.064), respectively. The concurring four clusters delineated by MrBayes and MYC, and four independent TCS networks, strongly confirmed their separate species status. In addition, An. konderi of Sallum should be regarded as unique with respect to the above. Despite initially being included as an outgroup taxon, this species falls well within the examined taxa, suggesting a combined analysis of these taxa would be most appropriate., Conclusions: Through novel data and retrospective comparison of available COI and ITS2 DNA sequences, evidence is shown to support the separate species status of An. oswaldoi s.s., An. oswaldoi A and An. oswaldoi B, and at least two species in the closely related An. konderi complex (An. sp. nr. konderi, An. konderi of Sallum). Although An. oswaldoi s.s. has never been implicated in malaria transmission, An. oswaldoi B is a confirmed vector and the new species An. oswaldoi A and An. sp. nr. konderi are circumstantially implicated, most likely acting as secondary vectors.

Domestic farm animals (n=145) were sampled for the presence of ectoparasites in northwestern Peru during March, 2008. Ninety domestic animals (62%) were positive for the presence of an ectoparasite(s) and produced a total collection of the following: 728 ticks [Amblyomma maculatum, Anocentor nitens, Rhipicephalus (Boophilus) microplus, Rhipicephalus sanguineus, and Otobius megnini], 12 lice (Haematopinus suis), and 3 fleas (Ctenocephalides felis). A Rickettsia genus-specific qPCR assay was performed on nucleic acid preparations of the collected ectoparasites that resulted in 5% (37/743, 35 ticks and 2 fleas) of the ectoparasites positive for the presence of Rickettsia. DNA from the positive individual ticks was tested with 2 other qPCR assays for the presence of the ompB gene in Candidatus Rickettsia andeanae or Rickettsia parkeri. Candidatus R. andeanae was found in 25 A. maculatum ticks and in two Rh. sanguineus ticks, whereas R. parkeri was detected in 6 A. maculatum ticks. Two A. maculatum were co-infected with both Candidatus R. andeanae and R. parkeri. Rickettsia felis was detected in 2 fleas, Ctenocephalides felis, by multilocus sequence typing of the 17-kD antigen and ompA genes. These findings expand the geographic range of R. parkeri to include Peru as well as expand the natural arthropod vector of Candidatus R. andeanae to include Rhipicephalus sanguineus.

The relations of Gf (Standard Progressive Matrices Raven), Gc (verbal scale of Wechsler Intelligence Scale for Children-Third Version), personality dimensions (Eysenck Personality Questionnaire-Junior Version), and disruptive behavior (TDAH scale) with school achievement (measured by TDE test and PISA test) were investigated. Two samples of students (total N = 534) representing a broad range of socioeconomic status (SES) participated in this study. Path models were conducted. The results demonstrated that (1) in both samples no sex differences related to school achievement were found; (2) in the first sample, after controlling for age and SES differences, Gf and psychoticism predicted (.38 and -.13, respectively) school achievement (measured by TDE test); (3) in the second sample, after controlling for SES differences to which additional measures were administered, Gf and Gc positively predicted (.22 and .40, respectively) school achievement (measured by PISA test). In addition, psychoticism and disruptive behavior also predicted school performance (-.14 and -.28, respectively). Some theoretical and practical implications are discussed.

Storage-oriented memory span tasks with no explicit concurrent processing are usually referred as short-term memory (STM) tasks, whereas tasks involving storage plus concurrent processing requirements are designated as working memory (WM) tasks. The present study explores a question that remains unsolved: Do STM and WM tasks clearly tap distinguishable theoretical constructs? For that purpose, a large sample of 403 participants was tested through 12 diverse memory span tasks. Half of those tasks are widely accepted as measures of STM, whereas the other half measure WM. The results show that STM and WM share largely overlapping underlying capacity limitations, suggesting that all memory span tasks tap essentially the same construct. Some implications are discussed.

Malaria, both Plasmodium falciparum (Welch) and Plasmodium vivax (Grassi & Feletti), has reemerged as a significant public health disease issue in Peru, especially in forested areas in the eastern part of the country. The spread of Anopheles darlingi Root, the principal South American malaria vector, into new areas of Peru is thought to be a factor in this resurgence. However, epidemiological evidence suggests that in malaria endemic areas of eastern Peru where An. darlingi does not occur, other species are involved in malaria transmission. The objective of this study was to analyze Anopheles species collected from 11 provinces within four departments in eastern Peru during 2001 and 2002 for infections with P. falciparum and P. vivax. More than 84,000 Anopheles mosquitoes representing 13 species were tested by enzyme-linked immunosorbent assay for the presence of Plasmodium circumsporozoite (CS) proteins. Of these, only An. darlingi and Anopheles benarrochi Gabaldón, Cova García & López were found positive. In total, 14 (0.98%) of 1,432 pools of An. darlingi were positive for Plasmodium species; specifically 10 (0.70%) pools were positive for P. falciparum, two (0.14%) were positive for P. vivax VK210, and two (0.14%) were positive for P. vivax VK247 proteins. Nine (0.14%) of 6,323 pools of An. benarrochi were positive for Plasmodium; five (0.08%) of 6,323 pools were positive for P. falciparum, two (0.03%) were positive for P. vivax VK247, one (0.02%) was positive for mixed P. vivax VK210/VK247 infections, and one (0.02%) was positive for mixed P. falciparum and P. vivax VK210 CS-proteins. Although infection rates in An. benarrochi were significantly lower (0.14%) than rates found for An. darlingi (0.98%), our data suggest that An. benarrochi may play a role in transmitting and maintaining Plasmodium species in various malaria endemic areas of eastern Peru.

Malaria has reemerged as a significant public health disease threat in Peru, especially within the Amazon Basin region. This resurgence of human cases caused by infection with Plasmodium falciparum and Plasmodium vivax is thought to be associated with the spread of Anopheles darlingi, the principal South American malaria vector, into new areas of the Amazon Basin. However, comprehensive studies of the distribution for this species have not been conducted in Peru for several years, nor are historical accounts accurate enough to determine if An. darlingi was actually present and not collected or misidentified. Therefore, the objective of this study is to define the distribution of An. darlingi as well as obtain data on distribution and abundance of other Anopheles species in this region. Mosquitoes were collected during 2001 in the Departments of Loreto and Ucayali, the two largest Amazonian Departments of Peru. A total of 60,585 specimens representing 12 species of the subgenera Nyssorhynchus and Anopheles were collected at 82 (88.2%) of 93 collecting sites. The majority of mosquitoes obtained were identified as An. benarrochi, comprising 70.7% of mosquitoes collected, followed by An. darlingi (24.0%), Anopheles mattogrosensis (2.4%), and Anopheles triannulatus (1.5%). Anopheles darlingi was collected from 48.8% of sites, indicating that this species is established throughout central Loreto, including further west in the Amazon Basin than previously reported. These data suggest that this species is now found in areas of the Amazon Basin region where it has not been previously reported.

Sequence divergence in the second internal transcribed spacer (ITS2) of ribosomal DNA was examined for female specimens of Anopheles oswaldoi Peryassu from 7 localities in South America. The lengths of ITS2 for all mosquitoes ranged from 348 to 356 nucleotides. After alignment of these sequences, similarity ranged from 87 to 100%. Divergence was within the range of inter-specific differences for members of anopheline species complexes. Therefore, specimens were placed into 4 groups that may correspond to at least 4 cryptic species. One is probably related to An. oswaldoi sensu stricto and another to Anopheles konderi Galvão & Damasceno. The other 2 groups may correspond to species for which morphological identification remains to be clarified. These data provide evidence that An. oswaldoi comprise a complex of cryptic species and that DNA identification may help to resolve the taxonomic questions related to this group.

We compared the susceptibility of Anopheles oswaldoi and An. konderi to infection by Plasmodium vivax based on the proportion of mosquitoes presenting oocysts and sporozoites. Anophelines were captured in the State of Acre and Rondônia, Brazilian Amazon, and used to obtain F1 progenies. After emergence of adults, male genitalia of mosquitoes of each family were dissected in order to identify them as either An. oswaldoi or An. konderi. F1 progenies of field-captured An. oswaldoi, An. konderi and An. darlingi (used as control) were fed simultaneously on P. vivax-infected blood. Mosquitoes were dissected on day 10-12 after feeding and examined for the presence of oocysts and sporozoites. Both An. oswaldoi and An. konderi developed oocysts in the midguts, however, the percentage of oocyst-positive mosquitoes for An. oswaldoi (13.8%) was higher than for An. konderi (3.3%), and only An. oswaldoi developed salivary infection with sporozoites (6.9% of positivity). Infection rates in An. darlingi ranged from 22.5% to 30.0% for both oocysts and sporozoites. These results indicate that An. oswaldoi can transmit P. vivax and suggest that it is more susceptible than An. konderi. Although An. oswaldoi is an exophilic and zoophilic species, it may be involved in malaria transmission as possibly occurred in the State of Acre.

From a total of 12,721 anophelines collected in a lowland area in Guaraí, Rio de Janeiro, from November 1991 to October 1992, 99.7% (12,688) were Anopheles aquasalis. This species occurred throughout the year, but in higher numbers from April to September, when rainfall was low or moderate. The proportion of parous females in June was significantly higher than the annual rate. An. aquasalis was weakly attracted by a light-trap, and no significant differences in abundance were detected between nights with and without moonlight.

Anopheles aquasalis has shown local variations in blood-host preference in Brazil: it seems to be anthropophilic in the northeast and zoophilic or opportunistic in the Amazon and other regions. A study was carried out in Guapimirim county, State of Rio de Janeiro, from May to November 1992, for the purpose of identifying the blood meal source of this anopheline by capillary tube precipitin test. A total of 1,366 females were captured at natural resting-places, 725 of which were blood-fed. The gut content of 473 blood fed females reacted to the antisera used (human, cow, horse, pig, dog and chicken). The majority of the females-356 (75.3%)-had blood from only one source. A substantial bovine preference was observed-52.2% had fed on cows, 29.8% on horses, 10.7% on pigs, 4.5% on chickens and 1.7% on dogs, but only few had fed on man (1.1%) and none on rats. On the other hand, 24.7% of the females had fed on more than one host, mainly on cows and horses. It was assumed that An. aquasalis is zoophilic in southeastern Brazil, feeding on a wide variety of animals, the cow being the primary host.

Percutaneous transluminal balloon angioplasty has been used successfully in the treatment of valvular and vascular stenosis. This article describes our experience with this technique to improve pulmonary blood flow in a patient with a severely stenotic Blalock-Taussig (B-T) systemic-to-right pulmonary artery anastomosis, with improvement in oxygen peripheric saturation from 33 to 78% immediately postdilatation and 69% three months later. Hemoglobin decreased from 20.4 to 18.9 gm/dl and hematocrit from 64% to 58.5%. In conclusion we think that this technique is an alternative instead of cardiac surgery, in these cases the procedure is only palliative.