Furuya Hiroyuki
Department of Basic Clinical Science and Public Health Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan.
Tokai J Exp Clin Med. 2013 Dec 20;38(4):135-41.
Exogenous reinfections in tuberculosis (TB) have been reported among elderly patients in long-term care facilities. This study estimated the impact of upper room ultraviolet germicidal irradiation (UVGI) and negative air ionization on the reduction in TB infection assuming that current TB control failed.
Estimated probability distributions RA, RM, RUV+M, and RIO+M, denoting the reproduction numbers of cases with no intervention, wearing surgical mask of infector, upper room UVGI, and negative ionization with wearing mask, respectively were determined.
It was assumed that 1 TB patient and 29 susceptibles stayed for 10 hours per day when ACH was 3; all subjects stayed for 60 consecutive days. The median RA increased from 7.38 (15th day) to 11.72 (two month). The percent reductions of RM, RUV+M, and RIO+M ranged from 52.4% (15th day) to 41.6% (two month), from 76.6% to 68.3%, and from 74.9% to 63.0%, respectively. The percent reductions of slopes; the change of median RM, RUV+M, and RIO+M for a change in length of stay, were estimated to be 50.8%, 87.3% and 73.7% when ACH was 1.
In addition to case detection and source control measures, environmental control measures may be effective in preventing exogenous reinfection of TB in elderly care facilities.
长期护理机构中的老年患者中已报告有结核病（TB）的外源性再感染情况。本研究估计了假设当前结核病控制措施失败时，上部空间紫外线杀菌辐照（UVGI）和负空气离子化对减少结核病感染的影响。
确定了估计的概率分布RA、RM、RUV+M和RIO+M，分别表示无干预、感染者佩戴外科口罩、上部空间UVGI以及佩戴口罩进行负空气离子化情况下病例的繁殖数。
假设当换气次数（ACH）为3时，1名结核病患者和29名易感者每天停留10小时；所有受试者连续停留60天。RA的中位数从第15天的7.38增加到两个月时的11.72。RM、RUV+M和RIO+M的降低百分比范围分别为从第15天的52.4%到两个月时的41.6%、从76.6%到68.3%以及从74.9%到63.0%。当ACH为1时，斜率的降低百分比；即停留时间变化时RM、RUV+M和RIO+M中位数的变化，估计分别为50.8%、87.3%和73.7%。
除病例发现和传染源控制措施外，环境控制措施可能对预防老年护理机构中结核病的外源性再感染有效。
