0 . 0026 " stated daniel farhoudi and colleagues at the swedish institute for infectious disease control . " the sharp downward trend in incidence seen in the period 1993 - 1998 appears to have halted 瑞典传染性疾病控制中心的daniel farhoudi和他的同事说， “ 1993 - 1998间疾病发生率急剧下降的趋势似乎已经停止。
