Severity of Attack Years since Haemorrhagic Confluent Abundant Sparse Very Totals Vacination Sparse ----------------------------------------------------------------------- 0- 10 0 1 6 11 12 30 10 - 25 5 37 114 165 136 457 25 - 45 29 155 299 268 181 932 Over 45 11 35 48 33 28 155 Unvaccinated 4 61 41 7 2 115 ----------------------------------------------------------------------- Totals 49 289 508 484 359 1689