Urbanisation, risk stratification and house infestation with a major vector of Chagas disease in an endemic municipality of the Argentine Chaco

Gaspe, María Sol; Fernández, María del Pilar; Cardinal, Marta Victoria; Enriquez, Gustavo Fabián; Rodríguez-Planes, Lucía I.; Macchiaverna, Natalia Paula; Gürtler, Ricardo E.

doi:10.1186/s13071-020-04182-3

Cited by 21 publications

(39 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A cross-sectional survey was conducted in all environments to evaluate house and domestic infestation with triatomines at baseline between October 2015 and March 2016, as described elsewhere [25]. In total, 2296 inhabited houses were surveyed.…”

Section: Methodsmentioning

confidence: 99%

“…Fieldwork was conducted in the municipality of Avia Terai (26°42′ S, 60°44′ W), Chaco Province, Argentina, which has been described elsewhere [25]. The last house spraying campaign with pyrethroid insecticides conducted by Chagas vector control personnel was carried out in 2011-2013 (2-4 years prior to our survey) and did not achieve full coverage.…”

Section: Study Areamentioning

confidence: 99%

“…The last house spraying campaign with pyrethroid insecticides conducted by Chagas vector control personnel was carried out in 2011-2013 (2-4 years prior to our survey) and did not achieve full coverage. For the purpose of this study, we divided the municipality into three environments based on house arrangement patterns: urban (blocks), peri-urban (blocks and dispersed houses) and rural (dispersed houses) [25]. The peri-urban environment was highly heterogeneous and was further subclassified into established and recent neighborhoods [25].…”

Section: Study Areamentioning

confidence: 99%

“…As part of an intervention program aimed at suppressing house infestation with T. infestans in a sustainable manner and reducing disease burden in Avia Terai, Argentine Chaco, we conducted a survey that found a decreasing prevalence of house infestation (i.e. domestic or/and peridomestic infestation) with T. infestans, ranging from 42.4% in rural houses to 22.5 and 4.5% in periurban and urban areas, respectively [25]. Domestic infestation, defined as the occurrence of T. infestans in human sleeping quarters or domiciles, also decreased across the rural-to-urban gradient, from 9.9 to 1.1%, respectively, as did the household number of domestic animals and peridomestic structures.…”

Section: Introductionmentioning

confidence: 99%

“…Domestic infestation, defined as the occurrence of T. infestans in human sleeping quarters or domiciles, also decreased across the rural-to-urban gradient, from 9.9 to 1.1%, respectively, as did the household number of domestic animals and peridomestic structures. Triatoma infestans seemed to be long established in Avia Terai, unlike in Arequipa and Cochabamba [17,25,26].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Trypanosoma cruzi infection in Triatoma infestans and high levels of human–vector contact across a rural-to-urban gradient in the Argentine Chaco

et al. 2021

Self Cite

View full text Add to dashboard Cite

Background Peri-urban and urban settings have recently gained more prominence in studies on vector-borne transmission of Trypanosoma cruzi due to sustained rural-to-urban migrations and reports of urban infestations with triatomines. Prompted by the finding of Triatoma infestans across the rural-to-urban gradient in Avia Terai, an endemic municipality of the Argentine Chaco, we assessed selected components of domestic transmission risk in order to determine its variation across the gradient. Methods A baseline vector survey was conducted between October 2015 and March 2016, following which we used multistage random sampling to select a representative sample of T. infestans at the municipal level. We assessed T. cruzi infection and blood-feeding sources of 561 insects collected from 109 houses using kinetoplast DNA-PCR assays and direct enzyme-linked immunosorbent assays, respectively. We stratified triatomines according to their collection site (domestic or peridomestic), and we further categorized peridomestic sites in ecotopes of low- or high-risk for T. cruzi infection. Results The overall adjusted prevalence of T. cruzi-infected T. infestans was 1.8% (95% confidence interval [CI] 1.3–2.3) and did not differ between peri-urban (1.7%) and rural (2.2%) environments. No infection was detected in bugs captured in the urban setting; rather, infected triatomines were mainly collected in rural and peri-urban domiciles, occurring in 8% of T. infestans-infested houses. The main blood-feeding sources of domestic and peridomestic triatomines across the gradient were humans and chickens, respectively. The proportion of triatomines that had fed on humans did not differ between peri-urban (62.5%) and rural (65.7%) domiciles, peaking in the few domestic triatomines collected in urban houses and decreasing significantly with an increasing proportion of chicken- and dog- or cat-fed bugs. The relative odds ratio (OR) of having a T. cruzi infection was nearly threefold higher in bugs having a blood meal on humans (OR 3.15), dogs (OR 2.80) or cats (OR: 4.02) in a Firth-penalized multiple logistic model. Conclusions Trypanosoma cruzi transmission was likely occurring both in peri-urban and rural houses of Avia Terai. Widespread infestation in a third of urban blocks combined with high levels of human–triatomine contact in the few infested domiciles implies a threat to urban inhabitants. Vector control strategies and surveillance originally conceived for rural areas should be tailored to peri-urban and urban settings in order to achieve sustainable interruption of domestic transmission in the Chaco region.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Study Areamentioning

confidence: 99%