Survival of adults and developmental stages ofSarcoptes scabiei var.canis when off the host

Abstract

All life-stages of Sarcoptes scabiei var. canis survive in the hosts' environment for several days to several weeks depending on r.h. and temperature. Survival of larvae was comparable to males; survival of nymphs was comparable to females. Females and nymphs generally survived longer than larvae and males. Low temperature (10-15 degrees) and high r.h. prolonged survival of all life stages. At 10-15 degrees C, females and nymphs survived 1-3 weeks at 97% r.h., 1-2 weeks at 75% r.h. and 5-8 days at 45% r.h. At 20-25 degrees C, survival was significantly reduced but all life-stages survived at least 2 days at 25% r.h. and 5-6 days at 75-100% r.h. Long survival off the host coupled with host-seeking behavior of these mites make it likely that environmental contamination is a source of scabies in domestic and wild mammals, and in humans.

Parasite invasion following host reintroduction: a case study of Yellowstone's wolves

“…The mites are capable of surviving away from a host for days and sometimes up to several weeks, depending on the microclimate at the mite's drop-off site [41]. Potential sites for environmental transmission include carcass sites, bed sites and dens.…”

DoesSarcoptes scabieisynchronize its breeding cycle with that of the Iberian Ibex,Capra pyrenaica?

“…In our study, all the 163 mite stages might potentially play a role in horizontal transmission of sarcoptic mange 164 during the rut period of hosts whereas nymphs might do so in vertical transmission as 165 their numbers peak in the birth period. 166 8 The parasite sex-ratio, biased toward females could reflect higher longevity and/or 167 survival of this sex (Arlian et al 1989;Hengge et al 2006), but also this is considered 168 as an adaptation to increase the reproductive potential (Price 1980;Esch and Fernandez 169 1993). It is interesting to note that sex-ratio peaked in May and November.…”

Pseudoectoparasites: a new tool for exploring the relationship between host behaviour and ectoparasites

“…The average life span of the free-living stages of ectoparasites such as sarcoptic mange, Sarcoptes scabiei, is less than 7 days in laboratory conditions resembling those in which natural infestations take place (Arlian et al 1989;Pé rez et al 1997). Since we used PEPs to explore how the host's behaviour affects infestations by contact-transmitted parasites such as Sarcoptes, we tested the stability of PEP characteristics over a week.…”

“…Second, we tested the stability of PEP characteristics over time and during different seasons. Given that PEPs are prone to desiccation, just as the survival of free-living stages of parasite species is determined by the climate (Arlian et al 1989;Tembely 1998;O'Connor et al 2006), we would expect a decrease in the infectivity of PEPs over time (prediction 1) and differences in the infectivity of PEPs between seasons (prediction 2). Third, in a medium-sized ungulate we tested the infectivity of such PEPs under a low invasive protocol (infestation of feeding points with PEPs) and then monitored the shortterm dynamics in PEPs on hosts as an indicator of infective persistence.…”