TABLE 2.

Kinetics of replication of influenza A/Duck/MN/525/81 (H5N1) virus in mouse tissuesa

Day after virus exposureMean virus titerb (no. of samplesc positive/total no. tested)
LungsPlasmaBrainKidneyLiverSpleen
16.3 ± 0.3 (5/5)5.8 (1/5)2.5 (1/5)<1.75 (0/5)<1.75 (0/5)<1.75 (0/5)
35.9 ± 0.3 (5/5)6.3 (1/5)<1.75 (0/5)<1.75 (0/5)<1.75 (0/5)<1.75 (0/5)
56.1 ± 0.3 (5/5)5.3 ± 1.4 (4/5)<1.75 (1/5)<1.75 (0/5)<1.75 (0/5)<1.75 (0/5)
75.5 ± 0.0 (1/1)<1.75 (0/1)1.75 (1/1)<1.75 (0/1)<1.75 (0/1)<1.75 (0/1)
  • a The virus challenge dose was 105.5 CCID50/ml.

  • b The titer of tissue or plasma yielding detectable virus (one experiment with five mice per time point).

  • c The tissue or plasma sample from which virus was detected (limit of method, 101.75 CCID50/g).