A country bug in the city: urban infestation by the Chagas disease vector Triatoma infestans in Arequipa, Peru

BACKGROUND:Interruption of vector-borne transmission of Trypanosoma cruzi remains an unrealized objective in many Latin American countries. The task of vector control is complicated by the emergence of vector insects in urban areas.METHODS:Utilizing data from a large-scale vector control program in Arequipa, Peru, we explored the spatial patterns of infestation by Triatoma infestans in an urban and peri-urban landscape. Multilevel logistic regression was utilized to assess the associations between household infestation and household- and locality-level socio-environmental measures.RESULTS:Of 37,229 households inspected for infestation, 6,982 (18.8%95% CI: 18.4 - 19.2%) were infested by T. infestans. Eighty clusters of infestation were identified, ranging in area from 0.1 to 68.7 hectares and containing as few as one and as many as 1,139 infested households. Spatial dependence between infested households was significant at distances up to 2,000 meters. Household T. infestans infestation was associated with household- and locality-level factors, including housing density, elevation, land surface temperature, and locality type.CONCLUSIONS:High levels of T. infestans infestation, characterized by spatial heterogeneity, were found across extensive urban and peri-urban areas prior to vector control. Several environmental and social factors, which may directly or indirectly influence the biology and behavior of T. infestans, were associated with infestation. Spatial clustering of infestation in the urban context may both challenge and inform surveillance and control of vector reemergence after insecticide intervention.This item is part of the UA Faculty Publications collection. For more information this item or other items in the UA Campus Repository, contact the University of Arizona Libraries at [email protected]

Chagas disease: an impediment in achieving the Millennium Development Goals in Latin America

<p>Abstract</p> <p>Background</p> <p>Achieving sustainable economic and social growth through advances in health is crucial in Latin America within the framework of the United Nations Millennium Development Goals.</p> <p>Discussion</p> <p>Health-related Millennium Development Goals need to incorporate a multidimensional approach addressing the specific epidemiologic profile for each region of the globe. In this regard, addressing the cycle of destitution and suffering associated with infection with <it>Trypanosoma cruzi</it>, the causal agent of Chagas disease of American trypanosomiasis, will play a key role to enable the most impoverished populations in Latin America the opportunity to achieve their full potential. Most cases of Chagas disease occur among forgotten populations because these diseases persist exclusively in the poorest and the most marginalized communities in Latin America.</p> <p>Summary</p> <p>Addressing the cycle of destitution and suffering associated with <it>T. cruzi </it>infection will contribute to improve the health of the most impoverished populations in Latin America and will ultimately grant them with the opportunity to achieve their full economic potential.</p

A Field Trial of Alternative Targeted Screening Strategies for Chagas Disease in Arequipa, Peru

In the wake of emerging T. cruzi infection in children of periurban Arequipa, Peru, we conducted a prospective field trial to evaluate alternative targeted screening strategies for Chagas disease across the city. Using insect vector data that is routinely collected during Ministry of Health insecticide application campaigns in 3 periurban districts of Arequipa, we separated into 4 categories those households with 1) infected vectors; 2) high vector densities; 3) low vector densities; and 4) no vectors. Residents of all infected-vector households and a random sample of those in the other 3 categories were invited for serological screening for T. cruzi infection. Subsequently, all residents of households within a 15-meter radius of detected seropositive individuals were invited to be screened in a ring case-detection scheme. Of 923 participants, 21 (2.28%) were seropositive. There were no significant differences in prevalence across the 4 screening strategies, indicating that household entomologic factors alone could not predict the risk of infection. Indeed, the most predictive variable of infection was the number of years a person lived in a location with triatomine insects. Therefore, a simple residence history questionnaire may be a useful screening tool in large, diverse urban environments with emerging Chagas disease

A History of Chagas Disease Transmission, Control, and Re-Emergence in Peri-Rural La Joya, Peru

The historically rural problem of Chagas disease is increasing in urban areas in Latin America. Peri-rural development may play a critical role in the urbanization of Chagas disease and other parasitic infections. We conducted a cross-sectional study in an urbanizing rural area in southern Peru, and we encountered a complex history of Chagas disease in this peri-rural environment. Specifically, we discovered: (1) long-standing parasite transmission leading to substantial burden of infection; (2) interruption in parasite transmission resulting from an undocumented insecticide application campaign; (3) relatively rapid re-emergence of parasite-infected vector insects resulting from an unsustained control campaign; (4) extensive migration among peri-rural inhabitants. Long-standing parasite infection in peri-rural areas with highly mobile populations provides a plausible mechanism for the expansion of parasite transmission to nearby urban centers. Lack of commitment to control campaigns in peri-rural areas may have unforeseen and undesired consequences for nearby urban centers. Novel methods and perspectives are needed to address the complexities of human migration and erratic interventions

Consumption oxygen by sStrains of espundia and uta (Leishmania) with monosaccharides

Se ha realizado un estudio comparativo de la respiración, y la acción de los monosacáridos (glucosa, fructosa, galactosa y manosa) sobre el consumo de oxigeno entre dos cepas de Leishmania provenientes de casos clínicos de leishmaniosis cutánea pura (uta) y de leishmaniosis cutáneo-mucosa (espundia) del Perú.This is a comparative study of respiration and mO:1osaccarid action (Glucose, Fructuose, Galactase ond Mannose) about oxygen consumption between two strains of Leishmania isolated from patients with cutaneous (uta) and muco-cutaneous leishmaniasis (espundia) from Peru

Molecular characterization of Echinococcus granulosus from Peru by sequencing of the mitochondrial cytochrome C oxidase subunit 1 gene

Echinococcus granulosus , the etiologic agent of cystic echinococcosis (CE) in humans and other animal species, is distributed worldwide. Ten intra-specific variants, or genotypes (G1-G10), have been defined based on genetic diversity. To determine the genotypes present in endemic areas of Peru, samples were collected from cattle (44), sheep (41) and humans (14) from Junín, Puno Huancavelica, Cusco, Arequipa and Ayacucho. DNA was extracted from protoscolex and/or germinal layers derived from 99 E. granulosus isolates and used as templates to amplify the mitochondrial cytochrome C oxidase subunit 1 gene. The resulting polymerase chain reaction products were sequenced and further examined by sequence analysis. All isolates, independent of the host, exhibited the G1 genotype. Phylogenetic analysis showed that three isolates from Ayacucho shared the same cluster with microvariant G14. The G1 genotype is considered the most widespread and infectious form of E. granulosus worldwide and our results confirm that the same patterns apply to this country. Therefore, these findings should be taken into consideration in developing prevention strategies and control programs for CE in Peru