Clinical signs, virus replication, and seroconversion in contact ferrets.

aNumber of animals with weight change/total number (maximum percent weight loss during the 21 days p.c.). bNumber of animals sneezing/total number during the 21 days p.c. (day of observed onset). cNumber of virus-shedding animals/total number. Numbers in parentheses indicate mean peak virus titer (log10TCID50/ml) in nasal wash samples). dThe first day of observation on which virus was not detected. eHemagglutination inhibition (HI) antibody titers to homologous virus in ferret serum on day 21 p.c. fDonor ferret was co-inoculated with A/DM/524/09 and A/DM/528/09 viruses at a 1∶1 ratio.