Pandemic response during the 1918 influenza pandemic: exploring non-pharmaceutical interventions in Norway

This study investigates the relationship between non-pharmaceutical interventions (NPIs) and influenza morbidity during the 1918 pandemic, with a focus on urban and rural medical districts in Norway. By integrating published secondary statistical data from 1918 from Statistics Norway with primary medical records from the Norwegian National Archive, the paper offers a novel historical data set to explore the timing and frequency of NPIs in relation to monthly reported influenza and pneumonia morbidity cases. Despite inherent limitations in the historical data, the findings suggest that a greater number of NPIs may have contributed to a delay in the onset and/or a reduction in the intensity of influenza morbidity. These results support the premise that the combined implementation of multiple NPIs was more effective in delaying and flattening the epidemic curve. The findings underscore the importance of early, coordinated and sustained non-pharmaceutical responses in mitigating the spread of infectious diseases, especially in the absence of pharmaceutical treatments or vaccines.