Non-viraemic transmission of Thogoto virus: vector efficiency of Rhipicephalus appendiculatus and Amblyomma variegatum.
Previous studies have demonstrated that Thogoto virus is transmitted from infected to uninfected ticks when co-feeding on uninfected guinea-pigs, even though the guinea-pigs do not develop a detectable viraemia. Furthermore, tick to tick transmission is potentiated by factors associated with the salivary glands of ticks (saliva activated transmission). The vector efficiency of 2 ixodid tick species, Rhipicephalus appendiculatus and Amblyomma variegatum, for Thogoto virus was assessed using this model. The number of uninfected recipient ticks that acquired Thogoto virus when co-feeding with virus-infected ticks (donors) on uninfected guinea-pigs was determined. When nymphs of either tick species were employed as donors, there was no significant difference in the number of infected recipient nymphs. In contrast, a significant difference in the vector efficiency of adults ticks was observed: 77.0% of recipient ticks which co-fed with R. appendiculatus donor adults acquired Thogoto virus compared to 44.7% of recipient ticks which co-fed with A. variegatum donors. No significant difference in susceptibility to Thogoto virus infection was observed between recipient ticks of the 2 species. Thus, adults of R. appendiculatus are more efficient than A. variegatum in mediating non-viraemic transmission.
Jones
L D
LD
Natural Environment Research Council, Institute of Virology and Environmental Microbiology, Oxford, UK.
Davies
C R
CR
Williams
T
T
Cory
J
J
Nuttall
P A
PA
D000818:Animals; D001096:Arachnid Vectors; D001102:Arbovirus Infections / Q000635:transmission*; D006224:Cricetinae; D006168:Guinea Pigs; D008647:Mesocricetus; D009758:Nymph; D013987:Ticks / Q000254:growth & development