Table 2 Comparison of reproduction number estimates for the A/H7N9 influenza viruses, other emerging zoonoses with pandemic potential, and human influenza viruses

A/H7N9 outbreak

Avian influenza A/H7N9- 2013, China

0.1 (95% CrI: 0.01 to 0.49)

This study; Bayesian approach from [11]

Avian influenza A/H7N9- 2013, China

0.03 to 0.05

This study; exposure-based approach from [20]

Avian influenza A/H7N9- 2013, China

0.28 (95% CI: 0.11 to 0.45)

Analysis of cluster size distribution from [22]

Other zoonotic influenza viruses

Avian influenza H5N1 -2003 to 2006, SE Asia and Egypt/Turkey

0.29

Cluster size distribution approach [21]; data from [29]

Avian influenza H5N1 – 2004 to 2006; SE Asia and Egypt/Turkey

0.52 to 0.54

[11] Bayesian approach

Swine influenza H3N2v - 2011, USA

0.5 to 0.74

Exposure-based approach [20]; data from [30]

Human influenza viruses

1918 A/H1N1 influenza pandemic

1.8 to 5.4

[16, 18, 31, 32] Various approaches

1957 A/H2N2 influenza pandemic

1.5

[33] growth rate

1968 A/H3N2 influenza pandemic

1.5

[33] growth rate

2009 A/H1N1 influenza pandemic

1.2 to 3.1

[17, 34–40] Various approaches

Seasonal influenza

1.3

[41, 42] growth rate

Other zoonotic viruses

Nipah virus, Malaysia, 1990s

0.05 to 0.08

Exposure-based approach [20]; data from [43]

Nipah virus, Bangladesh, 2000s

0.48 to 0.51

Exposure-based and cluster size distribution approaches [20]; to data from [21]

SARS virus, Singapore, Hong Kong, 2003

2.2 to 3.6

[15, 44] Epidemic model fitted to case series during the pre-intervention period