Active clinical trials for "Influenza, Human"

The purpose of this study is to generate data on immunogenicity and safety of the monovalent H1N1 vaccine in support of the development and registration. Primary objectives: To describe the immune response to vaccines 21 days after each vaccination in all participants. To describe the antibody persistence eight months after the first vaccine administration using hemagglutination inhibition (HAI) method in a subset of participants who received two half-doses of either formulation 1 or 2. To describe the immune response against the A/H1N1 strain using the HAI method 21 days after last vaccination with the 2010-2011 NH seasonal Trivalent Influenza Vaccine (TIV) administered 13 months after the first vaccination in a subset of subjects who received two half-doses of either t either formulation 1 or 2 of the A/H1N1 influenza vaccines as primary series. To describe the safety profile of each vaccine in all participants.

Influenza, a highly communicable acute respiratory disease, is one of the major infectious disease threats to the human population. In Africa, information on the occurrence of influenza and its disease burden is seriously lacking. Such data would be important in determining the contribution of influenza to the more than two million annual pneumonia deaths among children globally, mostly in the developing world, and the potential number of deaths that could be prevented by influenza vaccination. A single dose of trivalent inactivated influenza vaccine (TIV) is 70 to 90 percent effective in preventing influenza in healthy older children and young and middle-aged adults, but is less efficacious in young children and the elderly. Young children who suffer substantial influenza morbidity and are unlikely to have pre-existing immunity should receive two doses of TIV to provide adequate immunity. Because family studies of influenza transmission conducted during the 1970's found children to be the main introducers of influenza into households, vaccination of children may decrease the chances of spreading influenza to contacts. Mass vaccination of schoolchildren has been correlated with reduced respiratory illness in unvaccinated persons suggesting that immunization of children on a larger scale can affect community epidemics. In temperate industrialized countries with seasonal disease, influenza vaccine is given annually, prior to the influenza season, and generally targeted to individuals with the highest risk of severe disease. Influenza prevention strategies may need to differ in tropical developing countries due to a variety of reasons. Given the varying influenza circulation patterns, it is unknown which hemisphere vaccine formulation will provide year-round protection against the diverse strains that may exist in tropical countries. Persons residing in developing countries also may have nutritional deficiencies or underlying diseases and infections that affect vaccine immunogenicity. Consideration must be given to programmatic issues as well. Adolescent and adult preventive health services are poorly developed in many countries, and thus a strategy that targets children may be the most feasible option. In addition, vaccinating children may be the most cost-effective option, as it has the potential to provide direct benefit to those vaccinated, as well as indirect benefits to unvaccinated members of the population. Thus, an influenza vaccine effectiveness study in a tropical developing country population will help to elucidate burden of seasonal influenza and may inform optimal use of vaccine for either seasonal and pandemic situations. Thus, this study in Senegal will to evaluate the direct effects of TIV in reducing the occurrence of laboratory-confirmed influenza among children who receive it as well as the potential indirect effects experienced by the population as a result of reducing transmission among children.

A multi-center, open-label, escalating dose-ranging study to assess the safety, reactogenicity, and immunogenicity of four different VAX125 vaccine doses; 0.5 µg, 1.0 µg, 2.0 µg, or 3.0 µg, delivered i.m. as a single dose vaccination on Day 0. Hypothesis: VAX125 is safe and immunogenic at one or more of the doses tested.

The purpose of this study is to determine whether inactivated influenza vaccines are effective to protect school children and their households from getting influenza infection and further prevent student's absenteeism.

This trial will assess the immunogenicity and safety of GSK Biologicals' vaccine GSK1557484A, prepared from old concentrated monobulk material, in adults aged 18 to 64 years, when administered up to 5 years following production.

The purpose of this study is to determine the efficacy of the liquid formulation of CAIVT against culture confirmed influenza illness in healthy children aged at least 6 months and less than 36 months, attending day care centers in Europe. In addition, the trial provides the opportunity to investigate the effect of CAIV-T on acute otitis media, on healthcare resource utilization and economic resources.

To compare immune responses to measles, mumps, rubella, and varicella antigens following vaccination in children who receive FluMist concurrently with MMRIIÒ and VARIVAXÒ and in children who receive an intranasal placebo mist concurrently with MMRIIÒ and VARIVAXÒ (Group 2 vs. Group 1). To compare immune responses to the three strains of influenza (H1N1, H3N2, and B) following a two dose regimen of FluMist in children who receive the initial FluMist dose concurrently with MMRIIÒ and VARIVAXÒ and in children who receive two doses of FluMist alone (Group 2 vs. Group 3).Secondary: To assess the safety and tolerability of concurrent administration of FluMist with MMRIIÒ and VARIVAXÒ.

The purpose of this study is to determine whether having received an H5 vaccine in the past primes the immune system to respond rapidly to another dose of H5 vaccine. One hundred seventeen participants in a previous vaccine study (involving the A/Hong/Kong/97 virus) during the fall of 1998 at the University of Rochester will be eligible to enroll in this study. Participation in this study will up to 64 days and will involve donation of small samples of blood 7, 28, and 56 days after vaccination.

This is a complimentary study to an elderly influenza study. Subjects 18-40 will receive a single dose flu vaccine and be evaluated for humoral and cell mediated immunity to influenza antigens.

Besides the personal protection, influenza vaccination especially needs to prevent transmission of influenza between GPs and their patients. The question remains if the vaccine is adding substantial benefit to the natural acquired immunity of GPs. Doubts are raised if an inactivated vaccine, which elicit especially humoral immune response, can give enough protection against virus replication and subclinical influenza infections. Until now no effectiveness studies of influenza vaccination were performed among GPs. This study will assess the effectiveness of an inactivated influenza vaccine in GPs against clinical respiratory tract infections and more particular against influenza cases with influenza positive nose and throat swabs (diagnosed by RT-PCR).