The Department of Health and Human Services, specifically the Centers for Disease Control and Prevention (CDC), is seeking contractors for a Phase I project focused on developing serological assays for the detection and characterization of influenza viruses. The contract entails a 12-month base period with four additional 12-month option periods, aimed at testing immunological responses from human samples collected during vaccine effectiveness studies and outbreak investigations using Hemagglutination Inhibition (HAI) assays. This initiative is critical for enhancing the understanding of influenza vaccine efficacy and ensuring public health safety. Interested parties can contact Jennifer Gartzke at jgartzke@cdc.gov or by phone at 404-498-0020 for further details, as this opportunity is open for full competition due to previous insufficient small business participation.