Research Article

Persistence of Avian Influenza Viruses in Various Artificially Frozen Environmental Water Types

Table 2

Cumulative effect of experimental successive freezing-thawing cycles on AIV survival in lake water at −20°C (strain H7N1 A/northern pintail/Aomori/395/04).

Freezing and thawing cycleaVirus titer TCID50/mL (Log10)*Cumulative reduction (% TCID50)

First7.7511.4
Second720.0
Third6.7522.0
Fourth6.525.7

aFreezing conducted at −20°C for 75 minutes and thawing at +10°C for 10 minutes.
*Initial titer upon seeding was 8.75 log10 TCID50/mL.