Artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission
Abstract Background Artemisinin-based combination therapy (ACT) for treating malaria has activity against immature gametocytes. In theory, this property may complement the effect of terminating otherwise lengthy malaria infections and reducing the parasite reservoir in the human population that can...
Published in: | Malaria Journal |
---|---|
Main Authors: | , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
BMC
2012
|
Subjects: | |
Online Access: | https://doi.org/10.1186/1475-2875-11-118 https://doaj.org/article/7735dd8ecd244767907b42455744f80f |
id |
ftdoajarticles:oai:doaj.org/article:7735dd8ecd244767907b42455744f80f |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:7735dd8ecd244767907b42455744f80f 2023-05-15T15:15:11+02:00 Artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission Huho Bernadette J Killeen Gerard F Ferguson Heather M Tami Adriana Lengeler Christian Charlwood J Derek Kihonda Aniset Kihonda Japhet Kachur S Patrick Smith Thomas A Abdulla Salim MK 2012-04-01T00:00:00Z https://doi.org/10.1186/1475-2875-11-118 https://doaj.org/article/7735dd8ecd244767907b42455744f80f EN eng BMC http://www.malariajournal.com/content/11/1/118 https://doaj.org/toc/1475-2875 doi:10.1186/1475-2875-11-118 1475-2875 https://doaj.org/article/7735dd8ecd244767907b42455744f80f Malaria Journal, Vol 11, Iss 1, p 118 (2012) Malaria Artemisinin-based combination therapy Transmission reduction Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 article 2012 ftdoajarticles https://doi.org/10.1186/1475-2875-11-118 2022-12-31T10:20:51Z Abstract Background Artemisinin-based combination therapy (ACT) for treating malaria has activity against immature gametocytes. In theory, this property may complement the effect of terminating otherwise lengthy malaria infections and reducing the parasite reservoir in the human population that can infect vector mosquitoes. However, this has never been verified at a population level in a setting with intense transmission, where chronically infectious asymptomatic carriers are common and cured patients are rapidly and repeatedly re-infected. Methods From 2001 to 2004, malaria vector densities were monitored using light traps in three Tanzanian districts. Mosquitoes were dissected to determine parous and oocyst rates. Plasmodium falciparum sporozoite rates were determined by ELISA. Sulphadoxine-pyrimethamine (SP) monotherapy was used for treatment of uncomplicated malaria in the contiguous districts of Kilombero and Ulanga throughout this period. In Rufiji district, the standard drug was changed to artesunate co-administered with SP (AS + SP) in March 2003. The effects of this change in case management on malaria parasite infection in the vectors were analysed. Results Plasmodium falciparum entomological inoculation rates exceeded 300 infective bites per person per year at both sites over the whole period. The introduction of AS + SP in Rufiji was associated with increased oocyst prevalence (OR [95%CI] = 3.9 [2.9-5.3], p < 0.001), but had no consistent effect on sporozoite prevalence (OR [95%CI] = 0.9 [0.7-1.2], p = 0.5). The estimated infectiousness of the human population in Rufiji was very low prior to the change in drug policy. Emergence rates and parous rates of the vectors varied substantially throughout the study period, which affected estimates of infectiousness. The latter consequently cannot be explained by the change in drug policy. Conclusions In high perennial transmission settings, only a small proportion of infections in humans are symptomatic or treated, so case management with ACT may have ... Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic Malaria Journal 11 1 118 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Malaria Artemisinin-based combination therapy Transmission reduction Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 |
spellingShingle |
Malaria Artemisinin-based combination therapy Transmission reduction Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 Huho Bernadette J Killeen Gerard F Ferguson Heather M Tami Adriana Lengeler Christian Charlwood J Derek Kihonda Aniset Kihonda Japhet Kachur S Patrick Smith Thomas A Abdulla Salim MK Artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission |
topic_facet |
Malaria Artemisinin-based combination therapy Transmission reduction Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 |
description |
Abstract Background Artemisinin-based combination therapy (ACT) for treating malaria has activity against immature gametocytes. In theory, this property may complement the effect of terminating otherwise lengthy malaria infections and reducing the parasite reservoir in the human population that can infect vector mosquitoes. However, this has never been verified at a population level in a setting with intense transmission, where chronically infectious asymptomatic carriers are common and cured patients are rapidly and repeatedly re-infected. Methods From 2001 to 2004, malaria vector densities were monitored using light traps in three Tanzanian districts. Mosquitoes were dissected to determine parous and oocyst rates. Plasmodium falciparum sporozoite rates were determined by ELISA. Sulphadoxine-pyrimethamine (SP) monotherapy was used for treatment of uncomplicated malaria in the contiguous districts of Kilombero and Ulanga throughout this period. In Rufiji district, the standard drug was changed to artesunate co-administered with SP (AS + SP) in March 2003. The effects of this change in case management on malaria parasite infection in the vectors were analysed. Results Plasmodium falciparum entomological inoculation rates exceeded 300 infective bites per person per year at both sites over the whole period. The introduction of AS + SP in Rufiji was associated with increased oocyst prevalence (OR [95%CI] = 3.9 [2.9-5.3], p < 0.001), but had no consistent effect on sporozoite prevalence (OR [95%CI] = 0.9 [0.7-1.2], p = 0.5). The estimated infectiousness of the human population in Rufiji was very low prior to the change in drug policy. Emergence rates and parous rates of the vectors varied substantially throughout the study period, which affected estimates of infectiousness. The latter consequently cannot be explained by the change in drug policy. Conclusions In high perennial transmission settings, only a small proportion of infections in humans are symptomatic or treated, so case management with ACT may have ... |
format |
Article in Journal/Newspaper |
author |
Huho Bernadette J Killeen Gerard F Ferguson Heather M Tami Adriana Lengeler Christian Charlwood J Derek Kihonda Aniset Kihonda Japhet Kachur S Patrick Smith Thomas A Abdulla Salim MK |
author_facet |
Huho Bernadette J Killeen Gerard F Ferguson Heather M Tami Adriana Lengeler Christian Charlwood J Derek Kihonda Aniset Kihonda Japhet Kachur S Patrick Smith Thomas A Abdulla Salim MK |
author_sort |
Huho Bernadette J |
title |
Artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission |
title_short |
Artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission |
title_full |
Artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission |
title_fullStr |
Artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission |
title_full_unstemmed |
Artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission |
title_sort |
artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission |
publisher |
BMC |
publishDate |
2012 |
url |
https://doi.org/10.1186/1475-2875-11-118 https://doaj.org/article/7735dd8ecd244767907b42455744f80f |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
Malaria Journal, Vol 11, Iss 1, p 118 (2012) |
op_relation |
http://www.malariajournal.com/content/11/1/118 https://doaj.org/toc/1475-2875 doi:10.1186/1475-2875-11-118 1475-2875 https://doaj.org/article/7735dd8ecd244767907b42455744f80f |
op_doi |
https://doi.org/10.1186/1475-2875-11-118 |
container_title |
Malaria Journal |
container_volume |
11 |
container_issue |
1 |
container_start_page |
118 |
_version_ |
1766345568900087808 |