Safety and immunogenicity of trivalent inactivated influenza vaccine in infants: a randomized double-blind placebo-controlled study.
ABSTRACT Infants less than 6 months of age are at high risk for influenza disease and influenza-related complications, but no vaccine is licensed for this population.
A double-blind, randomized, placebo-controlled trial was conducted in 1375 healthy US infants 6 to 12 weeks of age. Subjects received 2 doses of trivalent inactivated influenza vaccine (TIV, Fluzone, sanofi pasteur; N = 915) or placebo (N = 460) 1 month apart in combination with indicated concomitant vaccines. Solicited adverse events were collected for 7 days following vaccination, and unsolicited adverse events for 28 days. Hemagglutination-inhibition antibodies to all 3 vaccine strains were measured following the second TIV/placebo dose.
No significant differences were seen between TIV and placebo groups for any safety outcome. Fever > or =38 degrees C within 3 days of vaccination was seen in 11.2% versus 11.7% of TIV versus placebo recipients. Serious adverse events within 28 days were reported in 1.9% of TIV and 1.5% of placebo recipients. Antibody responses to childhood vaccines were similar in both groups. Increased influenza-specific antibody responses in TIV recipients compared with placebo recipients were seen against all 3 strains in TIV recipients (P < 0.001), with better responses to influenza A strains noted. Reciprocal geometrical mean titer to H1N1, H3N2, and B were 33, 95, and 11 in TIV recipients versus 7, 9, and 5 for placebo recipients. Over 90% of TIV recipients had antibody > or =1:40 for at least 1 vaccine strain and 49.6% for 2 strains, versus 16.4% and 0.9% in placebo-recipients.
TIV administered to young infants beginning at 6 to 12 weeks of age is safe and immunogenic.
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ABSTRACT: This prospective study aimed to investigate the immune responses and safety of an influenza vaccine in vaccine-naïve infants aged 6-12 months, and was conducted from November 2010 to May 2011. Fifty-nine infants aged 6-12 months received two doses of trivalent inactivated influenza vaccine 4 weeks apart. Hemagglutination inhibition titers were measured 4 weeks after the two doses of study vaccine. Based on the assumption that a hemagglutination inhibition titer of 1:40 or greater against the antigen would be protective in adults, two doses of the study vaccine generated a protective immune response of 63.2% against influenza A(H1N1), 82.5% against influenza A(H3N2) and 38.6% against influenza B viruses in infants aged 6-12 months. The geometric mean fold rises against influenza type A and B viruses also met the European Medicines Agency criteria for flu vaccines. The solicited events within 7 days after vaccination were mild in intensity. No deaths or adverse events such as optic neuritis, cranial neuropathy, and brachial neuropathy or Guillain-Barre syndrome were reported. Two doses of inactivated influenza vaccine were well tolerated and induced a protective immune response against influenza in infants aged 6-12 months.Vaccine 03/2014; · 3.77 Impact Factor
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ABSTRACT: The source characteristics of the widespread Permian high Ti/Y basalts in the Emeishan Large Igneous Province (LIP) constitute important themes to evaluate the possible connection with a mantle plume beneath the Yangtze Block in southwestern China. Here we investigate the geochemical and isotopic signature of basalts from the Guangxi and Guizhou regions in the eastern margin of the Emeishan LIP and report the occurrence of high Ti/Y basalts in Guangxi. The zircons separated from Guangxi basalts yield a U–Pb concordia age of 257Ma, which is consistent with the age of the plume-related eruption of the Emeishan LIP. Both the Guangxi and Guizhou basalts studied here display evolved Sr–Nd isotopic composition and DUPAL Pb isotopic composition, with (87Sr/86Sr)i=0.705231 to 0.706147, positive to slightly negative εNd(t) values of −0.13 to +0.68, and △7=5–11, △8=70–84. The Guangxi basalts possess low SiO2 (44.82–49.71 wt.%), and TiO2 (2.29–3.54 wt.%), but are enriched in LREE and LILE with (La/Sm)N values of 2.2–2.6, high Ce/Yb ratios (19.6–30.0) and slightly negative Nb and Ta anomalies. The Guizhou basalts display higher SiO2 (47.49–50.27 wt.%), TiO2 (3.93–4.92 wt.%), Zr, Nb and La contents. They also show higher Ce/Yb (30.2–37.8) and Sm/Yb (3.56–4.19) ratios as compared to those of the Guangxi basalts, and do not possess negative Nb and Ta anomalies. The distinct differences between the Guangxi and Guizhou basalts may be caused by different degrees of partial melting of the garnet peridotite in their source region. We propose that the Guizhou basalts were derived from partial melting of metasomatized veins in the Yangtze continental lithosphere which were heated by the upwelling Emeishan plume, and the Guangxi basalts represent higher degrees of partial melting of the sub-continental lithospheric mantle and undergone minor crustal contamination during their ascent.Journal of Asian Earth Sciences - J ASIAN EARTH SCI. 01/2012;
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ABSTRACT: Renal transplant recipients (RTR) are considered at high risk for influenza-associated complications due to immunosuppression. The efficacy of standard influenza vaccination in RTRs is unclear. Hence, we evaluated activation of the adaptive immunity by the pandemic influenza A(H1N1) 2009 (A(H1N1)pdm09) vaccine in RTRs as compared to healthy controls. To determine cross-reactivity and/or bystander activation, seasonal trivalent influenza vaccine and tetanus/diphteria toxoid (TT/DT) vaccine-specific T cells along with allospecific T cells were quantified before and after A(H1N1)pdm09 vaccination. Vaccination-induced alloimmunity was additionally determined by quantifying serum creatinine and proinflammatory protein IP-10. Contrary to healthy controls, RTRs required a booster vaccination to achieve seroconversion (13.3 % day 21; 90 % day 90). In contrast to humoral immunity, sufficient A(H1N1)pdm09-specific T-cell responses were mounted in RTRs already after the first immunization with a magnitude comparable with healthy controls. Interestingly, vaccination simultaneously boosted T cells reacting to seasonal flu but not to TT/DT, suggesting cross-activation. No alloimmune effects were recorded. In conclusion, protective antibody responses required booster vaccination. However, sufficient cellular immunity is established already after the first vaccination, demonstrating differential kinetics of humoral and cellular immunity.Medical Microbiology and Immunology 09/2013; · 3.55 Impact Factor