Using serological diagnostics to characterize remaining high-incidence pockets of malaria in forest-fringe Cambodia
Abstract Background Over the last decades, the number of malaria cases has drastically reduced in Cambodia. As the overall prevalence of malaria in Cambodia declines, residual malaria transmission becomes increasingly fragmented over smaller remote regions. The aim of this study was to get an insigh...
| Main Authors: | , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2024-02-01
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| Series: | Malaria Journal |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s12936-024-04859-5 |
| _version_ | 1797275779268083712 |
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| author | Mathilde Grimée Costanza Tacoli Mirco Sandfort Thomas Obadia Aimee R. Taylor Amélie Vantaux Leanne J. Robinson Dysoley Lek Rhea J. Longley Ivo Mueller Jean Popovici Michael T. White Benoît Witkowski |
| author_facet | Mathilde Grimée Costanza Tacoli Mirco Sandfort Thomas Obadia Aimee R. Taylor Amélie Vantaux Leanne J. Robinson Dysoley Lek Rhea J. Longley Ivo Mueller Jean Popovici Michael T. White Benoît Witkowski |
| author_sort | Mathilde Grimée |
| collection | DOAJ |
| description | Abstract Background Over the last decades, the number of malaria cases has drastically reduced in Cambodia. As the overall prevalence of malaria in Cambodia declines, residual malaria transmission becomes increasingly fragmented over smaller remote regions. The aim of this study was to get an insight into the burden and epidemiological parameters of Plasmodium infections on the forest-fringe of Cambodia. Methods 950 participants were recruited in the province of Mondulkiri in Cambodia and followed up from 2018 to 2020. Whole-blood samples were processed for Plasmodium spp. identification by PCR as well as for a serological immunoassay. A risk factor analysis was conducted for Plasmodium vivax PCR-detected infections throughout the study, and for P. vivax seropositivity at baseline. To evaluate the predictive effect of seropositivity at baseline on subsequent PCR-positivity, an analysis of P. vivax infection-free survival time stratified by serological status at baseline was performed. Results Living inside the forest significantly increased the odds of P. vivax PCR-positivity by a factor of 18.3 (95% C.I. 7.7–43.5). Being a male adult was also a significant predictor of PCR-positivity. Similar risk profiles were identified for P. vivax seropositivity. The survival analysis showed that serological status at baseline significantly correlated with subsequent infection. Serology is most informative outside of the forest, where 94.0% (95% C.I. 90.7–97.4%) of seronegative individuals survived infection-free, compared to 32.4% (95% C.I.: 22.6–46.6%) of seropositive individuals. Conclusion This study justifies the need for serological diagnostic assays to target interventions in this region, particularly in demographic groups where a lot of risk heterogeneity persists, such as outside of the forest. |
| first_indexed | 2024-03-07T15:19:21Z |
| format | Article |
| id | doaj.art-c12ecb854bd64b19b26118c1d6c8b064 |
| institution | Directory Open Access Journal |
| issn | 1475-2875 |
| language | English |
| last_indexed | 2024-03-07T15:19:21Z |
| publishDate | 2024-02-01 |
| publisher | BMC |
| record_format | Article |
| series | Malaria Journal |
| spelling | doaj.art-c12ecb854bd64b19b26118c1d6c8b0642024-03-05T17:45:19ZengBMCMalaria Journal1475-28752024-02-0123111210.1186/s12936-024-04859-5Using serological diagnostics to characterize remaining high-incidence pockets of malaria in forest-fringe CambodiaMathilde Grimée0Costanza Tacoli1Mirco Sandfort2Thomas Obadia3Aimee R. Taylor4Amélie Vantaux5Leanne J. Robinson6Dysoley Lek7Rhea J. Longley8Ivo Mueller9Jean Popovici10Michael T. White11Benoît Witkowski12Infectious Disease Epidemiology and Analytics, Institut Pasteur, Université Paris CitéMalaria Research Unit, Institut Pasteur du CambodgeCollège Doctoral, Sorbonne UniversitéInfectious Disease Epidemiology and Analytics, Institut Pasteur, Université Paris CitéInfectious Disease Epidemiology and Analytics, Institut Pasteur, Université Paris CitéMalaria Research Unit, Institut Pasteur du CambodgeBurnet InstituteNational Centre for Parasitology, Entomology and Malaria ControlPopulation Health and Immunity, The Walter and Eliza Hall Institute of Medical ResearchMalaria Parasites and Hosts, Institut Pasteur, Université Paris CitéMalaria Research Unit, Institut Pasteur du CambodgeInfectious Disease Epidemiology and Analytics, Institut Pasteur, Université Paris CitéMalaria Research Unit, Institut Pasteur du CambodgeAbstract Background Over the last decades, the number of malaria cases has drastically reduced in Cambodia. As the overall prevalence of malaria in Cambodia declines, residual malaria transmission becomes increasingly fragmented over smaller remote regions. The aim of this study was to get an insight into the burden and epidemiological parameters of Plasmodium infections on the forest-fringe of Cambodia. Methods 950 participants were recruited in the province of Mondulkiri in Cambodia and followed up from 2018 to 2020. Whole-blood samples were processed for Plasmodium spp. identification by PCR as well as for a serological immunoassay. A risk factor analysis was conducted for Plasmodium vivax PCR-detected infections throughout the study, and for P. vivax seropositivity at baseline. To evaluate the predictive effect of seropositivity at baseline on subsequent PCR-positivity, an analysis of P. vivax infection-free survival time stratified by serological status at baseline was performed. Results Living inside the forest significantly increased the odds of P. vivax PCR-positivity by a factor of 18.3 (95% C.I. 7.7–43.5). Being a male adult was also a significant predictor of PCR-positivity. Similar risk profiles were identified for P. vivax seropositivity. The survival analysis showed that serological status at baseline significantly correlated with subsequent infection. Serology is most informative outside of the forest, where 94.0% (95% C.I. 90.7–97.4%) of seronegative individuals survived infection-free, compared to 32.4% (95% C.I.: 22.6–46.6%) of seropositive individuals. Conclusion This study justifies the need for serological diagnostic assays to target interventions in this region, particularly in demographic groups where a lot of risk heterogeneity persists, such as outside of the forest.https://doi.org/10.1186/s12936-024-04859-5Plasmodium vivaxSerologyRisk stratificationForestCambodiaGreater Mekong Subregion |
| spellingShingle | Mathilde Grimée Costanza Tacoli Mirco Sandfort Thomas Obadia Aimee R. Taylor Amélie Vantaux Leanne J. Robinson Dysoley Lek Rhea J. Longley Ivo Mueller Jean Popovici Michael T. White Benoît Witkowski Using serological diagnostics to characterize remaining high-incidence pockets of malaria in forest-fringe Cambodia Malaria Journal Plasmodium vivax Serology Risk stratification Forest Cambodia Greater Mekong Subregion |
| title | Using serological diagnostics to characterize remaining high-incidence pockets of malaria in forest-fringe Cambodia |
| title_full | Using serological diagnostics to characterize remaining high-incidence pockets of malaria in forest-fringe Cambodia |
| title_fullStr | Using serological diagnostics to characterize remaining high-incidence pockets of malaria in forest-fringe Cambodia |
| title_full_unstemmed | Using serological diagnostics to characterize remaining high-incidence pockets of malaria in forest-fringe Cambodia |
| title_short | Using serological diagnostics to characterize remaining high-incidence pockets of malaria in forest-fringe Cambodia |
| title_sort | using serological diagnostics to characterize remaining high incidence pockets of malaria in forest fringe cambodia |
| topic | Plasmodium vivax Serology Risk stratification Forest Cambodia Greater Mekong Subregion |
| url | https://doi.org/10.1186/s12936-024-04859-5 |
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