A study of squirrelpox virus in red and grey squirrels and an investigation of possible routes of transmission

................................................................................................................................. 10 CHAPTER 1 .......................................................................................................................... 12 INTRODUCTION ................................................................................................................. 12 1.1 History of squirrels in the UK ................................................................................... 12 1.1.1 Grey squirrels in the UK pre-1930 ................................................................. 12 1.1.2 Red squirrels in the UK pre-1930 .................................................................. 14 1.1.3 Distribution of red and grey squirrels in the UK post-1930 ........................... 15 1.1.4 Evidence of the role of disease in the decline of the red squirrel in the UK .. 17 1.1.5 Pox disease in red squirrels ............................................................................ 18 1.2 Poxviruses ................................................................................................................. 21 1.2.1 Taxonomic structure of Poxviridae ................................................................ 22 1.2.2 Virion morphology and structure ................................................................... 23 1.2.3 Genome features of poxviruses ...................................................................... 25 1.2.4 Poxvirus replication ....................................................................................... 27 1.2.5 Immunopathogenesis of poxvirus infection ................................................... 29 1.2.6 The role of the host in poxvirus pathogenesis: host tropism .......................... 32 1.2.7 Transmission of poxviruses ........................................................................... 33 1.3 Poxvirus infection in lagomorphs and rodents .......................................................... 35 1.3.1 Myxoma virus ................................................................................................ 35 1.3.2 Shope fibroma virus ....................................................................................... 36 1.3.3 Cowpox virus ................................................................................................. 36 1.3.4 Monkeypoxvirus ............................................................................................ 38 1.3.5 Squirrel fibroma virus .................................................................................... 39 1.3.6 Squirrelpox virus ............................................................................................ 41 1.4 Aim of the thesis ....................................................................................................... 42 CHAPTER 2 .......................................................................................................................... 44 MATERIALS AND METHODS ........................................................................................... 44 2.1 Centrifuges and Common reagents ........................................................................... 44 2.2 Sample storage .......................................................................................................... 44 2.3 Virology .................................................................................................................... 44