Transmission of Toxoplasma gondii in an urban population of domestic cats (Felis catus)

The Life Cycle of Toxoplasma gondii in the Natural Environment

“…The cat serological prevalences predicted by [10] agree with values observed along the urban rural gradient: when natural populations (as opposed to heterogeneous samples constituted from veterinary clinics or facilities) are considered, seroprevalences are clearly lower in urban (between 15 % to 26% [41,33,34,42,43]) than in rural areas (48% to 87.3% [44,30,45,32,42]). They also reach high values in non-anthropized areas: 51% in Kerguelen island [46].…”

“…In urban sites, even if incidence is low, very high densities of cats lead to expect a high number of infections: 165 infections per km² per year could occur in the dense population studied by Afonso et al [41,50]. In rural sites where cats live in density varying between 120 and 200 cats per km², [32] estimated that 31 to 72 infections per km² per year could occur.…”

“…Estimated levels of contamination by oocysts in five populations located in different environments. The table summarizes the studies of one population in a non-anthropized island (2 study sites) [46], three rural populations [32] and one urban population [41]. Oocyst burdens are estimated considering that an infected cat produces 25 millions oocysts.…”

“…The presence of such a resource can reduce the motivation to hunt in cats [16,59]. Observations made on urban cats in hunting activity are thus rare in such areas [41]. The altered predator-prey dynamics limits IH-HD T. gondii transmission, however toxoplasmosis does occur in urban hosts.…”

“…The altered predator-prey dynamics limits IH-HD T. gondii transmission, however toxoplasmosis does occur in urban hosts. Most surveys conducted in stray cats show low prevalences ranging from 5 to 20% [60,61,62,41] [64]. These cases may correspond to areas where cats have access to predation.…”