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Volume 3, Number 3—September 1997

Flea-borne Rickettsioses: Ecologic Considerations

Abdu F. AzadComments to Author , Suzana Radulovic, James A. Higgins, B. H. Noden, and Jill M. Troyer
Author affiliations: University of Maryland School of Medicine, Baltimore, Maryland, USA

Main Article

Table 3

Comparison of Rickettsia felis with other vector-borne Rickettsiae

Species Vector 190 kDaa 120/135kDab 17 kDac Hemolysis/plaqued Phylogenye
R. prowazekii louse - + + +/+ TG
R. typhi flea - + + +/+ TG
R. canada tick - + + -/- TG
R. felis flea - + + +/+ SFG
R. akari mite + + + -/+ SFG
R. australis tick - + + -/+ SFG
R. rickettsii tick + + + -/+ SFG
R. conorii tick + + + -/+ SFG

arOmpA (rickettsial outer membrane protein A). Although the presence of rOmpA gene sequences or gene product have not been shown in TG rickettsiae recently, DNA sequences fcorresponding to rOmpA were shown in the genome of R. prowazekii (24).
bAlso referred to rOmpB.
cAlso referred to as rickettsial inner membrane protein A.
dHemolysis of sheep red cells/plaque formation.
eTyphus group/spotted fever group rickettsiae.
+ indicates expression of gene products/growth characteristic.

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