What constitutes an influenza epidemic? I am not going to get too scientific and will not delve into issues such as increasing influenza rates, antigenic shifts, and antigen drifts.
Rather I offer you this perspective published in Clinical Infectious Diseases-on the 1918 "Spanish Flu" in Spain.
Public health officials in Valladolid argued with local authorities about formally declaring an influenza epidemic in 1918. City officials feared disruption of local holiday visitors and business activities, which were then supposedly at their peak.
Per Spanish law, if if physician died of influenza infection while on duty and if there was not an epidemic situation officially declared, then the widow was not entitled to receive a pension from the government. Thus, physicians put heavy pressure on the Mayor of Valladolid to officially and finally declare the 1918 epidemic of influenza in Spain.
If we feel that political and economic pressures do not factor into public health responses in the modern era, then we are deluding ourselves.