Effects of Maternal Influenza Immunization: A Field Trial in Guatemala'

描述（由申请人提供）：怀孕期间的感染可导致孕妇及其婴儿严重疾病，并可能对胎儿生长发育产生不利影响。流感病毒是一种重要的呼吸道病原体，可造成严重的疾病负担，包括孕妇和婴儿的发病率和死亡率。此外，与非孕妇和产后妇女相比，妊娠中期和晚期妇女患流感相关疾病的风险更高。疫苗接种是预防流感发病率和死亡率的最有效工具。孕妇流感免疫对母婴结局的潜在影响具有重要的临床和公共卫生意义。更好地了解母亲流感免疫对婴儿的影响可以提供一个重要的工具，以防治婴儿早期呼吸道疾病——不仅在发展中国家，而且在许多发达国家和中等收入国家，因为目前还没有批准用于6个月以下婴儿的流感疫苗。因此，我们建议进行一项随机、双盲、对照的疫苗试验

DESCRIPTION (provided by applicant): Infections during pregnancy can cause serious illness in pregnant women and their infants and can have an adverse impact on fetal growth and development. Influenza virus is an important respiratory pathogen that causes substantial burden of disease - including morbidity and mortality among pregnant women and young infants. Moreover, risk of influenza-related morbidity is higher in pregnant women in their second and third trimesters compared to non-pregnant and postpartum women. Vaccination is the most effective tool for preventing morbidity and mortality due to influenza. The potential impact of maternal influenza immunization on maternal and infant outcomes has important clinical and public health implications. Better understanding of infant effects of maternal influenza immunization could provide an important tool to combat respiratory disease in early infancy -not only in developing countries but also in many developed and middle income countries as there is no influenza vaccine currently approved for use in infants younger than 6 months. Therefore, we propose to conduct a randomized, double-blind, controlled, vaccine trial in Guatemala. The trial will be conducted at field sites in the departments (administrative units) of Quetzaltenango in western Guatemala and Santa Rosa in southern Guatemala. The enrollment will be conducted over three years; incorporating three influenza seasons. We will evaluate efficacy and safety of maternal immunization with inactivated influenza vaccine in a) pregnant women (before and after delivery) and b) their infants. The primary outcome of the proposed trial is laboratory (rRT-PCR) confirmed influenza infection in infants younger than 6 months. The secondary infant/fetus outcomes include clinical influenza-like illness, prematurity, birth weight, delivery complications, pneumonia and severe pneumonia (per WHO Integrated Management of Childhood Illness classification), hospitalizations due to severe acute respiratory illness, and adverse and severe adverse events. Moreover, secondary maternal outcomes include laboratory (rRT-PCR) confirmed influenza infection, clinical influenza-like illness, delivery complication, hospitalizations due to severe acute respiratory illness, and adverse and severe adverse events. We will also evaluate immunogenicity of the inactivated influenza vaccine by hemagglutination inhibition assay and microneutralization assay; and will estimate transplacental transfer of maternal influenza antibodies, infant antibody levels, and half life of antibodies acquired passively by infants. PUBLIC HEALTH RELEVANCE: Influenza infection during pregnancy can cause serious illness in pregnant women and their infants. Vaccination is the most effective tool for preventing morbidity and mortality due to influenza. However, currently there is no approved vaccine for infants younger than 6 months. Potential impact of maternal influenza immunization on maternal and infant outcomes has important clinical and public health implications. Therefore, we propose to conduct a randomized, double-blind, controlled, vaccine trial in Guatemala to evaluate the efficacy of influenza immunization in pregnancy for protecting mothers and their infants.