In:
PLOS Global Public Health, Public Library of Science (PLoS), Vol. 2, No. 9 ( 2022-9-7), p. e0000676-
Abstract:
Five years of sustained indoor residual spraying (IRS) of insecticide from 2014 to 2019, first using a carbamate followed by an organophosphate, was associated with a marked reduction in the incidence of malaria in five districts of Uganda. We assessed changes in malaria incidence over an additional 21 months, corresponding to a change in IRS formulations using clothianidin with and without deltamethrin. Using enhanced health facility surveillance data, our objectives were to 1) estimate the impact of IRS on monthly malaria case counts at five surveillance sites over a 6.75 year period, and 2) compare monthly case counts at five facilities receiving IRS to ten facilities in neighboring districts not receiving IRS. For both objectives, we specified mixed effects negative binomial regression models with random intercepts for surveillance site adjusting for rainfall, season, care-seeking, and malaria diagnostic. Following the implementation of IRS, cases were 84% lower in years 4–5 (adjusted incidence rate ratio [aIRR] = 0.16, 95% CI 0.12–0.22), 43% lower in year 6 (aIRR = 0.57, 95% CI 0.44–0.74), and 39% higher in the first 9 months of year 7 (aIRR = 1.39, 95% CI 0.97–1.97) compared to pre-IRS levels. Cases were 67% lower in IRS sites than non-IRS sites in year 6 (aIRR = 0.33, 95% CI 0.17–0.63) but 38% higher in the first 9 months of year 7 (aIRR = 1.38, 95% CI 0.90–2.11). We observed a resurgence in malaria to pre-IRS levels despite sustained IRS. The timing of this resurgence corresponded to a change of active ingredient. Further research is needed to determine causality.
Type of Medium:
Online Resource
ISSN:
2767-3375
DOI:
10.1371/journal.pgph.0000676
DOI:
10.1371/journal.pgph.0000676.g001
DOI:
10.1371/journal.pgph.0000676.g002
DOI:
10.1371/journal.pgph.0000676.g003
DOI:
10.1371/journal.pgph.0000676.g004
DOI:
10.1371/journal.pgph.0000676.g005
DOI:
10.1371/journal.pgph.0000676.t001
DOI:
10.1371/journal.pgph.0000676.t002
DOI:
10.1371/journal.pgph.0000676.s001
DOI:
10.1371/journal.pgph.0000676.s002
DOI:
10.1371/journal.pgph.0000676.s003
DOI:
10.1371/journal.pgph.0000676.s004
DOI:
10.1371/journal.pgph.0000676.s005
DOI:
10.1371/journal.pgph.0000676.s006
DOI:
10.1371/journal.pgph.0000676.s007
DOI:
10.1371/journal.pgph.0000676.r001
DOI:
10.1371/journal.pgph.0000676.r002
DOI:
10.1371/journal.pgph.0000676.r003
Language:
English
Publisher:
Public Library of Science (PLoS)
Publication Date:
2022
detail.hit.zdb_id:
3101394-6
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