To test the surface survival of the virus genome, replicate samples of the various materials were inoculated with 10 ml samples containing 1610 6 PFU of virus and incubated for defined periods of time before sample recovery was attempted by swabbing. It was noted that the liquid was absorbed by the wooden surfaces within 5 minutes whereas a droplet could be seen on non-porous surfaces for considerably longer, although in all cases, surfaces had dried by 7 hours. Material eluted from the swabs was then titred for virus genome by quantitative RT-PCR. For both PR8 (Fig. 1A , Table 2 ) and AH04 (Table 3) viruses the results were unambiguous. On most surfaces, the viral genome persisted well, with only around a 10-100 fold drop from the initially recoverable titre after 24 h. The exceptions were unsealed wood surfaces, where both viruses lost genome titre rapidly and on pine surfaces in particular, became undetectable after a few hours. Thus in general, viral RNA survives well for at least 24 h and few surfaces had any significant 'contact effect' in immediately reducing genome titre.