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.
Parasite
Test material
Test conditions
12°C 50% RH
25°C 50% RH
37°C 70% RH
NS
S
NS
S
NS
S
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).