Workplace influenza vaccination in two major industries in saudi arabia: a cost benefit analysis

This study aimed at evaluating the effectiveness of mass Influenza vaccination on workers health and costs reductions. We compared 1396 Influenza vaccinated workers versus 1004 not vaccinated workers from same workplaces, regarding outcome of interests, like frequency of Influenza Like Illnesses (ILI), frequency of physician office visits due to ILI, sick leaves due to ILI, and cost benefit analysis and cost saving analysis in two major industries in Riyadh; food processing, and chemical industries. The goal of vaccination coverage was 80%, but the maximum coverage reached was 58%. Average sick-leave days reduction during the 4 months follow up period was from 1.27 days/worker in the no vaccine group to 0.31 days/worker in the vaccine group (p<0.001). Also, there is a reduction in the average number of physician office visits from 0.99/worker in the no vaccine group to 0.23 days/worker in the vaccine group (p<0.001); with relative risk reduction of ILI among vaccinated workers to 0.37 (0.31<95%CI< 0.44) compared to no vaccine group. Combined data from the two industries showed a net saving of about 28 US$ per each vaccinated worker.