The United States has experienced a shortage of inactivated influenza vaccine during the last 3 influenza seasons, leaving many patients at risk.1 The possibility of extending existing vaccine supplies by using an alternative intradermal route of vaccination that requires smaller doses as a means of “stretching” available doses of influenza vaccine could have important public health implications. This would enable, despite the current limited supply of the vaccine, vaccination of many more patients than would otherwise be possible. During the influenza season of 2004-2005 and facing a shortage of influenza vaccine in our clinics, we consulted with our central institutional review board and decided to study this potential alternative. The AIDS Healthcare Foundation operates 4 major and 5 satellite clinics throughout the Los Angeles (Calif) metropolitan area. Our objective was to compare the immunogenicity and safety of the candidate vaccine administered intradermally at a reduced dose (0.1 mL) with the reference influenza vaccine administered intramuscularly at the standard dose (0.5 mL). We compared antibody responses to reduced intradermal dosing of the influenza vaccine with standard intramuscular dosing in human immunodeficiency virus–positive patients. The patients were randomized on a 2:1 basis to arm A (receiving 0.1 mL of influenza vaccine via intradermal injection) or arm B (receiving 0.5 mL of influenza vaccine via intramuscular injection).
Khanlou H, Sanchez S, Babaie M, Chien C, Hamwi G, Ricaurte J, Stein T, Bhatti L, Denouden P, Farthing C. The Safety and Efficacy of Dose-Sparing Intradermal Administration of Influenza Vaccine in Human Immunodeficiency Virus–Positive Patients. Arch Intern Med. 2006;166(13):1417. doi:10.1001/archinte.166.13.1417