What you should know about the Covid-19 vaccines from top experts in the field. As the SARS-Cov2 virus emerged and spread globally in early 2020, unprecedented international efforts began to develop and test vaccines to control the devastating pandemic. This book focuses on the remarkable progress in developing vaccines, the amazing effectiveness of the early vaccines, and the challenges of delivering them to the population. To put this extraordinary progress into perspective, the history of other vaccines is presented and their roles in individual protection and protection of the community, "vaccines that protect the unvaccinated," are outlined. The rigorous processes whereby vaccines are evaluated in distinct phases and the steps that must be met prior to obtaining regulatory approval for both vaccine safety and effectiveness are highlighted. Multiple vaccine approaches are reviewed, including new approaches such as "messenger or mRNA vaccine" that may revolutionize future vaccine development. The comprehensive models used to provide recommendations and priorities for vaccination of groups of people at risk are summarized. The book also focuses on the questions that remain unanswered after the vaccines are approved. These include duration of immunity, risk factors for vaccine failure, impact of viral evolution and variant strains, and assessment of both immediate and long-term safety. The authors also address concerns about vaccine acceptance including roll-out, access, and detailed and trusted sources of information.

Among the writers of the Syriac Christian tradition, none is as renowned as St. Ephrem of Nisibis (ca. 307-373), known to much of the later Christian world simply as "the Syrian." The great majority of Ephrem's works are poetry, with the madrase ("teaching songs") especially prominent. This volume presents English translations of four complete madrase cycles of Ephrem: On the Fast, On the Unleavened Bread, On the Crucifixion, and On the Resurrection. These collections include some of the most liturgically oriented songs in Ephrem's corpus, and, as such, provide a window into the celebration of Lent and Easter in the Syriac-speaking churches of northern Mesopotamia in the fourth century. Even more significantly, they represent some of the oldest surviving poetry composed for these liturgical seasons in the entire Christian tradition. Not only are the liturgical occasions of the springtime months a source of colorful imagery in these texts, but Ephrem also employs traditional motifs of warm weather, spring rainstorms, and revived vegetation, which likely reflect Hellenistic literary influences. Like all of Ephrem's poetry, these songs express early Christian theology in language that is symbolic, terse, and vibrant. They are rich with biblical allusions and references, especially to the Exodus and Passion narratives. They also reveal a contested religious environment in which Ephrem strove to promote the Christian Pascha and Christian interpretations of Scripture over and against those of Jewish communities in the region, thus maintaining firm boundaries around the identity and practices of the churches.