Chagas disease vector control in a hyperendemic setting: the first 11 years of intervention in Cochabamba, Bolivia.
BACKGROUND: Chagas disease has historically been hyperendemic in the Bolivian Department of Cochabamba. In the early 2000s, an extensive vector control program was implemented; 1.34 million dwelling inspections were conducted to ascertain infestation (2000-2001/2003-2011), with blanket insecticide s...
Published in: | PLoS Neglected Tropical Diseases |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Public Library of Science (PLoS)
2014
|
Subjects: | |
Online Access: | https://doi.org/10.1371/journal.pntd.0002782 https://doaj.org/article/abcea059f5814053b5682b84cc2c4178 |
id |
ftdoajarticles:oai:doaj.org/article:abcea059f5814053b5682b84cc2c4178 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:abcea059f5814053b5682b84cc2c4178 2023-05-15T15:15:09+02:00 Chagas disease vector control in a hyperendemic setting: the first 11 years of intervention in Cochabamba, Bolivia. Natalisisy Espinoza Rafael Borrás Fernando Abad-Franch 2014-04-01T00:00:00Z https://doi.org/10.1371/journal.pntd.0002782 https://doaj.org/article/abcea059f5814053b5682b84cc2c4178 EN eng Public Library of Science (PLoS) http://europepmc.org/articles/PMC3974664?pdf=render https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0002782 https://doaj.org/article/abcea059f5814053b5682b84cc2c4178 PLoS Neglected Tropical Diseases, Vol 8, Iss 4, p e2782 (2014) Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 article 2014 ftdoajarticles https://doi.org/10.1371/journal.pntd.0002782 2022-12-31T12:48:21Z BACKGROUND: Chagas disease has historically been hyperendemic in the Bolivian Department of Cochabamba. In the early 2000s, an extensive vector control program was implemented; 1.34 million dwelling inspections were conducted to ascertain infestation (2000-2001/2003-2011), with blanket insecticide spraying in 2003-2005 and subsequent survey-spraying cycles targeting residual infestation foci. Here, we assess the effects of this program on dwelling infestation rates (DIRs). METHODOLOGY/PRINCIPAL FINDINGS: Program records were used to calculate annual, municipality-level aggregate DIRs (39 municipalities); very high values in 2000-2001 (median: 0.77-0.69) dropped to ∼0.03 from 2004 on. A linear mixed model (with municipality as a random factor) suggested that infestation odds decreased, on average, by ∼28% (95% confidence interval [CI95] 6-44%) with each 10-fold increase in control effort. A second, better-fitting mixed model including year as an ordinal predictor disclosed large DIR reductions in 2001-2003 (odds ratio [OR] 0.11, CI95 0.06-0.19) and 2003-2004 (OR 0.22, CI95 0.14-0.34). Except for a moderate decrease in 2005-2006, no significant changes were detected afterwards. In both models, municipality-level DIRs correlated positively with previous-year DIRs and with the extent of municipal territory originally covered by montane dry forests. CONCLUSIONS/SIGNIFICANCE: Insecticide-spraying campaigns had very strong, long-lasting effects on DIRs in Cochabamba. However, post-intervention surveys consistently detected infestation in ∼3% of dwellings, underscoring the need for continuous surveillance; higher DIRs were recorded in the capital city and, more generally, in municipalities dominated by montane dry forest--an eco-region where wild Triatoma infestans are widespread. Traditional strategies combining insecticide spraying and longitudinal surveillance are thus confirmed as very effective means for area-wide Chagas disease vector control; they will be particularly beneficial in highly-endemic settings, but ... Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic PLoS Neglected Tropical Diseases 8 4 e2782 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
spellingShingle |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 Natalisisy Espinoza Rafael Borrás Fernando Abad-Franch Chagas disease vector control in a hyperendemic setting: the first 11 years of intervention in Cochabamba, Bolivia. |
topic_facet |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
description |
BACKGROUND: Chagas disease has historically been hyperendemic in the Bolivian Department of Cochabamba. In the early 2000s, an extensive vector control program was implemented; 1.34 million dwelling inspections were conducted to ascertain infestation (2000-2001/2003-2011), with blanket insecticide spraying in 2003-2005 and subsequent survey-spraying cycles targeting residual infestation foci. Here, we assess the effects of this program on dwelling infestation rates (DIRs). METHODOLOGY/PRINCIPAL FINDINGS: Program records were used to calculate annual, municipality-level aggregate DIRs (39 municipalities); very high values in 2000-2001 (median: 0.77-0.69) dropped to ∼0.03 from 2004 on. A linear mixed model (with municipality as a random factor) suggested that infestation odds decreased, on average, by ∼28% (95% confidence interval [CI95] 6-44%) with each 10-fold increase in control effort. A second, better-fitting mixed model including year as an ordinal predictor disclosed large DIR reductions in 2001-2003 (odds ratio [OR] 0.11, CI95 0.06-0.19) and 2003-2004 (OR 0.22, CI95 0.14-0.34). Except for a moderate decrease in 2005-2006, no significant changes were detected afterwards. In both models, municipality-level DIRs correlated positively with previous-year DIRs and with the extent of municipal territory originally covered by montane dry forests. CONCLUSIONS/SIGNIFICANCE: Insecticide-spraying campaigns had very strong, long-lasting effects on DIRs in Cochabamba. However, post-intervention surveys consistently detected infestation in ∼3% of dwellings, underscoring the need for continuous surveillance; higher DIRs were recorded in the capital city and, more generally, in municipalities dominated by montane dry forest--an eco-region where wild Triatoma infestans are widespread. Traditional strategies combining insecticide spraying and longitudinal surveillance are thus confirmed as very effective means for area-wide Chagas disease vector control; they will be particularly beneficial in highly-endemic settings, but ... |
format |
Article in Journal/Newspaper |
author |
Natalisisy Espinoza Rafael Borrás Fernando Abad-Franch |
author_facet |
Natalisisy Espinoza Rafael Borrás Fernando Abad-Franch |
author_sort |
Natalisisy Espinoza |
title |
Chagas disease vector control in a hyperendemic setting: the first 11 years of intervention in Cochabamba, Bolivia. |
title_short |
Chagas disease vector control in a hyperendemic setting: the first 11 years of intervention in Cochabamba, Bolivia. |
title_full |
Chagas disease vector control in a hyperendemic setting: the first 11 years of intervention in Cochabamba, Bolivia. |
title_fullStr |
Chagas disease vector control in a hyperendemic setting: the first 11 years of intervention in Cochabamba, Bolivia. |
title_full_unstemmed |
Chagas disease vector control in a hyperendemic setting: the first 11 years of intervention in Cochabamba, Bolivia. |
title_sort |
chagas disease vector control in a hyperendemic setting: the first 11 years of intervention in cochabamba, bolivia. |
publisher |
Public Library of Science (PLoS) |
publishDate |
2014 |
url |
https://doi.org/10.1371/journal.pntd.0002782 https://doaj.org/article/abcea059f5814053b5682b84cc2c4178 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
PLoS Neglected Tropical Diseases, Vol 8, Iss 4, p e2782 (2014) |
op_relation |
http://europepmc.org/articles/PMC3974664?pdf=render https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0002782 https://doaj.org/article/abcea059f5814053b5682b84cc2c4178 |
op_doi |
https://doi.org/10.1371/journal.pntd.0002782 |
container_title |
PLoS Neglected Tropical Diseases |
container_volume |
8 |
container_issue |
4 |
container_start_page |
e2782 |
_version_ |
1766345531454390272 |