TABLE 1

Respiratory droplet transmission studies with H7N9 influenza viruses, 2013

Study authorsFerret genderFerret ageInoculum vol (μl)aInoculum dosebTotal no. of:% overall RD transmissioneReference
VirusescFerretsd
Zhu et al.Male1.5 yr500106 TCID50136688
Zhang et al.Female4 mo500106 EID503126675
Belser et al.Male7–8 mo1,000106 PFU293389
Watanabe et al.Female5–8 mo500106 PFU133390
Richard et al.Female1–2 yr500106 TCID50147591
Xu et al.Male6–12 moNR106 TCID50133392
  • a Volume of virus delivered intranasally to anesthetized ferrets. NR, not reported.

  • b Dose of virus used to inoculate ferrets. TCID50, 50% tissue culture infectious dose; EID50, 50% egg infectious dose.

  • c Total number of unique wild-type H7N9 viruses isolated from human cases included in the study.

  • d Total number of pairs of inoculated and contact ferrets used in the study to determine virus transmissibility.

  • e Percentage of transmission events detected among all pairs of inoculated and contact ferrets tested. All transmission events were defined as virus isolation from contact ferrets, with the exception of one ferret in the study by Zhu et al. (88) that seroconverted in the absence of virus detection. RD, respiratory droplet.