Why are there so few Rickettsia conorii conorii-infected Rhipicephalus sanguineus ticks in the wild?
Background Rickettsia conorii conorii is the etiological agent of Mediterranean spotted fever, which is transmitted by the brown dog tick, Rhipicephalus sanguineus. The relationship between the Rickettsia and its tick vector are still poorly understood one century after the first description of this...
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ftdoajarticles:oai:doaj.org/article:bb89036469394a37a75377dfbaa3a03c 2023-05-15T15:15:28+02:00 Why are there so few Rickettsia conorii conorii-infected Rhipicephalus sanguineus ticks in the wild? Cristina Socolovschi Jean Gaudart Idir Bitam Thi Phong Huynh Didier Raoult Philippe Parola 2012-01-01T00:00:00Z https://doi.org/10.1371/journal.pntd.0001697 https://doaj.org/article/bb89036469394a37a75377dfbaa3a03c EN eng Public Library of Science (PLoS) https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/22724035/?tool=EBI https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0001697 https://doaj.org/article/bb89036469394a37a75377dfbaa3a03c PLoS Neglected Tropical Diseases, Vol 6, Iss 6, p e1697 (2012) Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 article 2012 ftdoajarticles https://doi.org/10.1371/journal.pntd.0001697 2022-12-31T07:46:18Z Background Rickettsia conorii conorii is the etiological agent of Mediterranean spotted fever, which is transmitted by the brown dog tick, Rhipicephalus sanguineus. The relationship between the Rickettsia and its tick vector are still poorly understood one century after the first description of this disease. Methodology/principal findings An entomological survey was organized in Algeria to collect ticks from the houses of patients with spotted fever signs. Colonies of R. conorii conorii-infected and non-infected ticks were established under laboratory conditions. Gimenez staining and electron microscopy on the ovaries of infected ticks indicated heavy rickettsial infection. The transovarial transmission of R. conorii conorii in naturally infected Rh. sanguineus ticks was 100% at eleven generations, and the filial infection rate was up to 99% according to molecular analyses. No differences in life cycle duration were observed between infected and non-infected ticks held at 25°C, but the average weight of engorged females and eggs was significantly lower in infected ticks than in non-infected ticks. The eggs, larvae and unfed nymphs of infected and non-infected ticks could not tolerate low (4°C) or high (37°C) temperatures or long starvation periods. R. conorii conorii-infected engorged nymphs that were exposed to a low or high temperature for one month experienced higher mortality when they were transferred to 25°C than non-infected ticks after similar exposure. High mortality was observed in infected adults that were maintained for one month at a low or high temperature after tick-feeding on rabbits. Conclusion/significance These preliminary results suggest that infected quiescent ticks may not survive the winter and may help explain the low prevalence of infected Rh. sanguineus in nature. Further investigations on the influence of extrinsic factors on diapaused R. conorii-infected and non-infected ticks are required. Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic PLoS Neglected Tropical Diseases 6 6 e1697 |
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Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
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English |
topic |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
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Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 Cristina Socolovschi Jean Gaudart Idir Bitam Thi Phong Huynh Didier Raoult Philippe Parola Why are there so few Rickettsia conorii conorii-infected Rhipicephalus sanguineus ticks in the wild? |
topic_facet |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
description |
Background Rickettsia conorii conorii is the etiological agent of Mediterranean spotted fever, which is transmitted by the brown dog tick, Rhipicephalus sanguineus. The relationship between the Rickettsia and its tick vector are still poorly understood one century after the first description of this disease. Methodology/principal findings An entomological survey was organized in Algeria to collect ticks from the houses of patients with spotted fever signs. Colonies of R. conorii conorii-infected and non-infected ticks were established under laboratory conditions. Gimenez staining and electron microscopy on the ovaries of infected ticks indicated heavy rickettsial infection. The transovarial transmission of R. conorii conorii in naturally infected Rh. sanguineus ticks was 100% at eleven generations, and the filial infection rate was up to 99% according to molecular analyses. No differences in life cycle duration were observed between infected and non-infected ticks held at 25°C, but the average weight of engorged females and eggs was significantly lower in infected ticks than in non-infected ticks. The eggs, larvae and unfed nymphs of infected and non-infected ticks could not tolerate low (4°C) or high (37°C) temperatures or long starvation periods. R. conorii conorii-infected engorged nymphs that were exposed to a low or high temperature for one month experienced higher mortality when they were transferred to 25°C than non-infected ticks after similar exposure. High mortality was observed in infected adults that were maintained for one month at a low or high temperature after tick-feeding on rabbits. Conclusion/significance These preliminary results suggest that infected quiescent ticks may not survive the winter and may help explain the low prevalence of infected Rh. sanguineus in nature. Further investigations on the influence of extrinsic factors on diapaused R. conorii-infected and non-infected ticks are required. |
format |
Article in Journal/Newspaper |
author |
Cristina Socolovschi Jean Gaudart Idir Bitam Thi Phong Huynh Didier Raoult Philippe Parola |
author_facet |
Cristina Socolovschi Jean Gaudart Idir Bitam Thi Phong Huynh Didier Raoult Philippe Parola |
author_sort |
Cristina Socolovschi |
title |
Why are there so few Rickettsia conorii conorii-infected Rhipicephalus sanguineus ticks in the wild? |
title_short |
Why are there so few Rickettsia conorii conorii-infected Rhipicephalus sanguineus ticks in the wild? |
title_full |
Why are there so few Rickettsia conorii conorii-infected Rhipicephalus sanguineus ticks in the wild? |
title_fullStr |
Why are there so few Rickettsia conorii conorii-infected Rhipicephalus sanguineus ticks in the wild? |
title_full_unstemmed |
Why are there so few Rickettsia conorii conorii-infected Rhipicephalus sanguineus ticks in the wild? |
title_sort |
why are there so few rickettsia conorii conorii-infected rhipicephalus sanguineus ticks in the wild? |
publisher |
Public Library of Science (PLoS) |
publishDate |
2012 |
url |
https://doi.org/10.1371/journal.pntd.0001697 https://doaj.org/article/bb89036469394a37a75377dfbaa3a03c |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
PLoS Neglected Tropical Diseases, Vol 6, Iss 6, p e1697 (2012) |
op_relation |
https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/22724035/?tool=EBI https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0001697 https://doaj.org/article/bb89036469394a37a75377dfbaa3a03c |
op_doi |
https://doi.org/10.1371/journal.pntd.0001697 |
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PLoS Neglected Tropical Diseases |
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6 |
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6 |
container_start_page |
e1697 |
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1766345845499756544 |