Table 3.
Changes in the Basic Reproduction Number (R0) Between Waves of the H3N2 Influenza Pandemic of 1968
| Setting | First Wave | Second Wave | ||
| R0 | 95% CI | R0 | 95% CI | |
| United Kingdom (RCGP data) | 1.26 | 1.24, 1.28 | 2.08 | 2.04, 2.12 |
| United Kingdom (survey of PHLS samples) | 2.00 | 1.57, 2.43 | 2.78 | 2.33, 3.23 |
| United Kingdom (laboratory reports to PHLS) | 1.44 | 1.42, 1.46 | 2.66 | 2.43, 2.90 |
| England and Walesa | 1.26 | 1.24, 1.28 | 2.42 | 2.05, 2.82 |
| Scotland | 1.37 | 1.32, 1.42 | 2.16 | 2.04, 2.28 |
| Lambeth, London, United Kingdom | 1.54 | 1.13, 1.95 | 2.77 | 1.93, 3.61 |
| São Paulo, Brazil | 2.06 | 1.77, 2.35 | 3.58 | 1.95, 5.21 |
| Sydney, New South Wales, Australia | 1.31 | 1.04, 1.58 | 2.04 | 1.59, 2.49 |
| Epping, New South Wales, Australia | 1.16 | 0.92, 1.41 | 2.12 | 1.78, 2.46 |
| Royal Air Force bases, England | 1.13 | 0.89, 1.37 | 1.86 | 1.60, 2.12 |
Abbreviations: CI, confidence interval; PHLS, Public Health Laboratory Service; RCGP, Royal College of General Practitioners.
a
First-wave estimate was based on clinical data; second-wave estimate was based on laboratory reports.