The production of IgE specific to different viruses (HIV-1, Parvovirus B19, Parainfluenza virus, Varicella Zoster Virus), and the ability of IgE anti-HIV-1 to suppress HIV-1 production in vitro, strongly suggest an important role for IgE and/or anti viral specific IgE in viral pathogenesis. Nevertheless, the presence and persistence of IgE anti-Influenza virus antibodies has not been studied. Total serum IgE and specific IgE and IgG anti-Influenza virus antibodies were studied in children (N=3) (m/f 14-16 y/o) and adults (N=3) (m/f, 41-49 y/o) 2-20 months after vaccination with Influenza virus (Flumist® or Fluzone®), as well as in non-vaccinated children (N=2). (UniCAP total IgE Fluoroenzymeimmunoassay, ELISA, Immunoblot). We found that serum of vaccinated children and adults contained IgE and IgG anti-Influenza virus antibodies approaching two years post vaccination. Non-vaccinated children did not make either IgE or IgG anti-Influenza antibodies. Similar levels of IL-2, IFN-γ, IL-4, and IL-10 cytokines were detected in serum of vaccinated compared with non vaccinated subjects (p>0.05), as well as between vaccinated adults compared with vaccinated children and non vaccinated subjects (p>0.05). Vaccinated children and adults continue to produce IgE anti-Influenza virus antibodies long term post vaccination. The long term production of IgE anti-Influenza virus antibodies induced by vaccination may contribute to protective immunity against Influenza.