View clinical trials related to Vaccine Virus Shedding.
Filter by:This study generates robust, uniform clinical data across emerging COVID-19 strains to train ML/AI algorithms of the Sponsor's imPulse™ Una infrasound-to-ultrasound e-stethoscope for digital diagnostic feature synthesis of asymptomatic and symptomatic COVID-19 digital biosignatures for rapid and accurate adult and child mass screening.
Intranasal live attenuated influenza vaccine (LAIV; trade name FluMist/Fluenz-Tetra, manufactured by AstraZeneca/Medimmune) is the standard influenza vaccine given to children aged 2-17 years of age in the UK. It is also licensed to be given to adults up to the age of 49 years in the USA. The systems biology of the human blood response to influenza vaccines has been studied in great detail, but there is a paramount need to study innate and specific, soluble and cellular immune responses at the nasal mucosal site of influenza infection. In this way this study aims to determine correlates of efficacy and vaccine take in serum and nasal mucosal lining fluid (MLF).
Rotavirus is the leading cause of diarrhea in children worldwide. Oral rotavirus vaccines work remarkably well in high-income countries, but for unclear reasons they underperform in low-income countries. A double-blind, randomized control trial will be performed to evaluate whether using a higher dose of a currently licensed vaccine (Rotarix, GlaxoSmithKline) can improve immune responses among infants in Dhaka, Bangladesh. Infants will be randomized 1:1 to receive either a standard or a double dose of Rotarix at 6 and 10 weeks of life. Infants will be assessed for fecal vaccine shedding and serum rotavirus-specific IgA responses to determine vaccine immunogenicity.
The Strategic Advisory Group of Experts on Immunization (SAGE) has set a plan to replace trivalent oral polio vaccine (tOPV) with bivalent OPV (bOPV) plus inactivated polio vaccine (IPV) in routine immunization globally, to be instituted in 2015-2016. At the community level, the impact of the change from tOPV + IPV to bOPV + IPV on Sabin virus fecal-oral transmission (duration of circulation, degree of genetic reversion) and the persistence of environmental contamination are unknown. Also unknown is the impact of the change from tOPV to bOPV on community circulation of Sabin 2 after a special immunization (SI) activity with monovalent oral poliovirus type 2 (mOPV2). Finally it is unknown at the level of an individual child if type 2 fecal shedding will be limited by cross-protection from oral vaccination with Sabin type 1 and 3. The investigators propose to measure at a community level transmission of Sabin 2 virus in Bangladesh, a low income country, where fecal-oral transmission and environmental exposures are high, comparing transmission in the setting of vaccination with tOPV+IPV vs. bOPV+IPV. The study will be conducted in 67 villages in Matlab, Bangladesh, using a cluster-randomized study design. Villages in Matlab will be randomly assigned to receive as part of routine immunization (RI) activities: (1) tOPV (6,10,14 weeks) plus IPV at 14 weeks; (2) bOPV (6,10, 14 weeks) plus IPV at 14 weeks; or (3) bOPV (6,10, 14 weeks) plus IPV at 14 and 18 weeks. Community and environmental surveillance for Sabin 2 virus will be conducted in each village over the 9 month period of these RI activities. In addition, a SI activity with mOPV2 will occur 9 months into the study to model an outbreak response. For the 6 months following the mOPV2 challenge, the impact of the different vaccination regimens on Sabin 2 transmission in the community will be determined, as well as individual level protection (as measured by fecal shedding from days 7-70 after mOPV2 challenge).
Oral polio and rotavirus vaccines are significantly less effective in children living in the developing world. Tropical enteropathy, which is associated with intestinal inflammation, decreased absorption and increased permeability, may contribute substantially to oral vaccine failure in developing country settings. Other possible causes of oral vaccine underperformance include malnutrition, interference with maternal or breastmilk antibodies, changes in gut microbiota, and genetic susceptibility. Primary Objective: to determine whether tropical enteropathy impairs the efficacy of oral polio and rotavirus vaccines in children in Bangladesh. Secondary Objectives: 1) to determine the impact of an inactivated polio vaccine (IPV) boost on the efficacy of oral polio vaccine and 2) to determine the efficacy of oral rotavirus vaccine to prevent rotavirus diarrhea The polio and rotavirus randomized clinical trials are embedded as secondary objectives within the exploratory study of tropical enteropathy. The primary and secondary outcome measures are relevant to the randomized clinical trials.