Research Article

Impact of Environmental Conditions on the Survival of Cryptosporidium and Giardia on Environmental Surfaces

Table 1

Summary of die-off rates (the first-order values) of Giardia cysts and Cryptosporidium oocysts on a variety of surfaces incubated in different environmental conditions.

ParasiteTest materialTest conditions
12°C 50% RH25°C 50% RH37°C 70% RH
NSSNSSNSS

Giardia Fabric −0.24609−0.3409−0.45487−0.39509−0.54514−0.5132
Ceramic−0.2572−0.29622−0.35363−0.28729−0.36001−0.47733
Formica−0.2572−0.29622−0.33656−0.28729−0.36001−0.48086
Skin −0.14704−0.11569−0.25754−0.20598−0.74951−0.6331
Stainless steel−0.34612−0.35842−0.7764−1.04699−0.89851−1.07793
Average −0.25073−0.28149−0.4358−0.44453−0.58264−0.63648

Cryptosporidium Fabric−0.16294−0.09118−0.58958−0.5037−1.08403−0.85624
Ceramic −0.46996−0.40785−0.58958−0.5037−1.08403−0.85624
Formica−0.0663−0.04954−0.58958−0.5037−0.81303−0.64218
Skin −0.04837−0.04609−0.09552−0.08723−0.16308−0.13251
Stainless steel −0.46996−0.40785−0.58958−0.5037−1.08403−0.85624
Average −0.24351−0.2005−0.49077−0.42041−0.84564−0.66868

S: surface soiled with 5% organic matter; NS: surface not soiled (clean).