Cargando…

Demographic patterns of human antibody levels to Simulium damnosum s.l. saliva in onchocerciasis-endemic areas: An indicator of exposure to vector bites

BACKGROUND: In onchocerciasis endemic areas in Africa, heterogenous biting rates by blackfly vectors on humans are assumed to partially explain age- and sex-dependent infection patterns with Onchocerca volvulus. To underpin these assumptions and further improve predictions made by onchocerciasis tra...

Descripción completa

Detalles Bibliográficos
Autores principales: Willen, Laura, Milton, Philip, Hamley, Jonathan I. D., Walker, Martin, Osei-Atweneboana, Mike Y., Volf, Petr, Basáñez, Maria-Gloria, Courtenay, Orin
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8789114/
https://www.ncbi.nlm.nih.gov/pubmed/35020729
http://dx.doi.org/10.1371/journal.pntd.0010108
_version_ 1784639695385264128
author Willen, Laura
Milton, Philip
Hamley, Jonathan I. D.
Walker, Martin
Osei-Atweneboana, Mike Y.
Volf, Petr
Basáñez, Maria-Gloria
Courtenay, Orin
author_facet Willen, Laura
Milton, Philip
Hamley, Jonathan I. D.
Walker, Martin
Osei-Atweneboana, Mike Y.
Volf, Petr
Basáñez, Maria-Gloria
Courtenay, Orin
author_sort Willen, Laura
collection PubMed
description BACKGROUND: In onchocerciasis endemic areas in Africa, heterogenous biting rates by blackfly vectors on humans are assumed to partially explain age- and sex-dependent infection patterns with Onchocerca volvulus. To underpin these assumptions and further improve predictions made by onchocerciasis transmission models, demographic patterns in antibody responses to salivary antigens of Simulium damnosum s.l. are evaluated as a measure of blackfly exposure. METHODOLOGY/PRINCIPAL FINDINGS: Recently developed IgG and IgM anti-saliva immunoassays for S. damnosum s.l. were applied to blood samples collected from residents in four onchocerciasis endemic villages in Ghana. Demographic patterns in antibody levels according to village, sex and age were explored by fitting generalized linear models. Antibody levels varied between villages but showed consistent patterns with age and sex. Both IgG and IgM responses declined with increasing age. IgG responses were generally lower in males than in females and exhibited a steeper decline in adult males than in adult females. No sex-specific difference was observed in IgM responses. CONCLUSIONS/SIGNIFICANCE: The decline in age-specific antibody patterns suggested development of immunotolerance or desensitization to blackfly saliva antigen in response to persistent exposure. The variation between sexes, and between adults and youngsters may reflect differences in behaviour influencing cumulative exposure. These measures of antibody acquisition and decay could be incorporated into onchocerciasis transmission models towards informing onchocerciasis control, elimination, and surveillance.
format Online
Article
Text
id pubmed-8789114
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher Public Library of Science
record_format MEDLINE/PubMed
spelling pubmed-87891142022-01-26 Demographic patterns of human antibody levels to Simulium damnosum s.l. saliva in onchocerciasis-endemic areas: An indicator of exposure to vector bites Willen, Laura Milton, Philip Hamley, Jonathan I. D. Walker, Martin Osei-Atweneboana, Mike Y. Volf, Petr Basáñez, Maria-Gloria Courtenay, Orin PLoS Negl Trop Dis Research Article BACKGROUND: In onchocerciasis endemic areas in Africa, heterogenous biting rates by blackfly vectors on humans are assumed to partially explain age- and sex-dependent infection patterns with Onchocerca volvulus. To underpin these assumptions and further improve predictions made by onchocerciasis transmission models, demographic patterns in antibody responses to salivary antigens of Simulium damnosum s.l. are evaluated as a measure of blackfly exposure. METHODOLOGY/PRINCIPAL FINDINGS: Recently developed IgG and IgM anti-saliva immunoassays for S. damnosum s.l. were applied to blood samples collected from residents in four onchocerciasis endemic villages in Ghana. Demographic patterns in antibody levels according to village, sex and age were explored by fitting generalized linear models. Antibody levels varied between villages but showed consistent patterns with age and sex. Both IgG and IgM responses declined with increasing age. IgG responses were generally lower in males than in females and exhibited a steeper decline in adult males than in adult females. No sex-specific difference was observed in IgM responses. CONCLUSIONS/SIGNIFICANCE: The decline in age-specific antibody patterns suggested development of immunotolerance or desensitization to blackfly saliva antigen in response to persistent exposure. The variation between sexes, and between adults and youngsters may reflect differences in behaviour influencing cumulative exposure. These measures of antibody acquisition and decay could be incorporated into onchocerciasis transmission models towards informing onchocerciasis control, elimination, and surveillance. Public Library of Science 2022-01-12 /pmc/articles/PMC8789114/ /pubmed/35020729 http://dx.doi.org/10.1371/journal.pntd.0010108 Text en © 2022 Willen et al https://creativecommons.org/licenses/by/4.0/This is an open access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
spellingShingle Research Article
Willen, Laura
Milton, Philip
Hamley, Jonathan I. D.
Walker, Martin
Osei-Atweneboana, Mike Y.
Volf, Petr
Basáñez, Maria-Gloria
Courtenay, Orin
Demographic patterns of human antibody levels to Simulium damnosum s.l. saliva in onchocerciasis-endemic areas: An indicator of exposure to vector bites
title Demographic patterns of human antibody levels to Simulium damnosum s.l. saliva in onchocerciasis-endemic areas: An indicator of exposure to vector bites
title_full Demographic patterns of human antibody levels to Simulium damnosum s.l. saliva in onchocerciasis-endemic areas: An indicator of exposure to vector bites
title_fullStr Demographic patterns of human antibody levels to Simulium damnosum s.l. saliva in onchocerciasis-endemic areas: An indicator of exposure to vector bites
title_full_unstemmed Demographic patterns of human antibody levels to Simulium damnosum s.l. saliva in onchocerciasis-endemic areas: An indicator of exposure to vector bites
title_short Demographic patterns of human antibody levels to Simulium damnosum s.l. saliva in onchocerciasis-endemic areas: An indicator of exposure to vector bites
title_sort demographic patterns of human antibody levels to simulium damnosum s.l. saliva in onchocerciasis-endemic areas: an indicator of exposure to vector bites
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8789114/
https://www.ncbi.nlm.nih.gov/pubmed/35020729
http://dx.doi.org/10.1371/journal.pntd.0010108
work_keys_str_mv AT willenlaura demographicpatternsofhumanantibodylevelstosimuliumdamnosumslsalivainonchocerciasisendemicareasanindicatorofexposuretovectorbites
AT miltonphilip demographicpatternsofhumanantibodylevelstosimuliumdamnosumslsalivainonchocerciasisendemicareasanindicatorofexposuretovectorbites
AT hamleyjonathanid demographicpatternsofhumanantibodylevelstosimuliumdamnosumslsalivainonchocerciasisendemicareasanindicatorofexposuretovectorbites
AT walkermartin demographicpatternsofhumanantibodylevelstosimuliumdamnosumslsalivainonchocerciasisendemicareasanindicatorofexposuretovectorbites
AT oseiatweneboanamikey demographicpatternsofhumanantibodylevelstosimuliumdamnosumslsalivainonchocerciasisendemicareasanindicatorofexposuretovectorbites
AT volfpetr demographicpatternsofhumanantibodylevelstosimuliumdamnosumslsalivainonchocerciasisendemicareasanindicatorofexposuretovectorbites
AT basanezmariagloria demographicpatternsofhumanantibodylevelstosimuliumdamnosumslsalivainonchocerciasisendemicareasanindicatorofexposuretovectorbites
AT courtenayorin demographicpatternsofhumanantibodylevelstosimuliumdamnosumslsalivainonchocerciasisendemicareasanindicatorofexposuretovectorbites