Reservoir competence of various rodents for the lyme disease Spirochete Borrelia spielmanii

Abstract

To determine whether the pathogenic Lyme disease spirochete Borrelia spielmanii is adapted exclusively to garden dormice, we compared the reservoir competence of various rodent species for this spirochete, including sympatric and peridomestic rodents. The different kinds of rodents varied in their attractiveness to nymphal ticks and their level of susceptibility to tick-borne B. spielmanii infection, but only the edible dormouse appeared to be refractory. Although hazel dormice and Norway rats became infectious to ticks somewhat later than did garden dormice, they remained infectious for a longer period of time. During the course of a tick season, garden and hazel dormice contributed theoretically more than twice as many B. spielmanii-infected ticks than the somewhat less susceptible Norway rats and wood or yellow-necked mice. Hazel dormice appeared to be extraordinarily competent as reservoir hosts for B. spielmanii. Because peridomestic rodents proved to be reservoir competent, urban foci of transmission of B. spielmanii may affect the health of townspeople.

Fig. 1.

Degree and duration of infectivity of various rodents infected with Borrelia spielmanii for xenodiagnostic larvae. Each thin line represents the infectivity of an individual host, the broad continuous line displays the mean infectivity, and the broken line displays the mean infectivity of garden dormice as a comparison. (A) Garden dormice; (B) hazel dormice; (C) wood mice; (D) yellow-necked mice; (E) Norway rats; (F) house mice.

Fig. 2.

Degree and duration of infectivity of garden dormice upon two reinfections with tick-borne Borrelia spielmanii. Each thin line represents the infectivity of an individual host, and the broad line displays the mean infectivity.