Typbar TCV® Vaccine Study in Malawi (IMAGE) University of Maryland School of Medicine Caption Healthy children in Malawi participating in study to test efficacy of typhoid conjugate vaccine. Credit TyVAC/Madalitso Mvula Usage Restrictions No restrictions. License Public Domain Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.