Comparison of efficacy of American and african Amblyomma ticks as vectors of heartwater (Cowdria ruminantium) infection by molecular analyses and transmission trials

Mahan Suman M., Peter Trevor F., Simbi Bigboy H., Kocan Katherine M., Camus Emmanuel, Barbet Anthony F., Burridge Michael J.. 2000. Comparison of efficacy of American and african Amblyomma ticks as vectors of heartwater (Cowdria ruminantium) infection by molecular analyses and transmission trials. Journal of Parasitology, 86 (1) : 44-49.

Liste HCERES des revues (en SHS) : oui

Thème(s) HCERES des revues (en SHS) : Psychologie-éthologie-ergonomie

Résumé : The ability of Amblyomma americanum, Amblyomma cajennense, Amblyomma maculatum, and Amblyomma variegatum to acquire and transmit Cowdria ruminantium infection was investigated. Uninfected nymphs were fed on clinically reacting C. ruminantium-infected sheep and then analyzed for infection by specific DNA detection assays and by tick transmission trials. By polymerase chain reaction (PCR), the mean infection prevalence of A. maculatum ticks (50.7%) was similar to that of A. variegatum, Elevage strain (43.5%; P = 0.83) and Petit Bourg strain (45.9%; P = 0.26) ticks. Though Amblyomma hebraeum were not tested by PCR, by DNA probe their infection prevalence was 94%. In contrast, A. americanum and A. cajennense ticks demonstrated very low susceptibility to C. ruminantium, and the prevalence of infection by PCR was approximately 1%. The higher susceptibility of A. maculatum and A. variegatum to C. ruminantium correlated with superior vector efficiency, depicted by similar prepatent periods and severity of disease transmissions to sheep. Amblyomma americanum and A. cajennense failed to transmit infection, confirming that low susceptibility to C. ruminantium correlates with the poor vector status of these species. These results highlight the importance of A. maculatum as a potential vector that is likely to play a major role in the establishment and maintenance of heartwater, if the disease were to be introduced to the U.S.A., Central, and South America.

Mots-clés Agrovoc : Amblyomma americanum, Amblyomma variegatum, Ehrlichia ruminantium, vecteur de maladie, Amblyomma maculatum, Amblyomma hebraeum

Classification Agris : L72 - Organismes nuisibles des animaux

Auteurs et affiliations

• Mahan Suman M., University of Florida (USA)
• Peter Trevor F., USAID (ZWE)
• Simbi Bigboy H.
• Kocan Katherine M., Oklahoma State University (USA)
• Camus Emmanuel, CIRAD-EMVT-SANTE ANIMALE (FRA)
• Barbet Anthony F., University of Florida (USA)
• Burridge Michael J., University of Florida (USA)

Source : Cirad - Agritrop (https://agritrop.cirad.fr/477814/)

Métriques

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