Abstract：
OBJECTIVE: Parainfluenza virus type 3 (PIV3) outbreaks among hematology patients are associated with high morbidity and mortality. Prompt implementation of infection prevention (IP) measures has proven to be the most efficacious approach for controlling PIV3 outbreaks within this patient population. The most suitable IP measures can vary depending on the mode of virus transmission, which remains unidentified in most outbreaks. We describe the molecular epidemiology of an outbreak of PIV3 among hematology patients and the development of a new method that allows for the differentiation of outbreak and community strains, from which a closed outbreak could be inferred.
METHODS: Patients were screened for respiratory viruses using multiplex-PCR. PIV3 positive samples with a cycle threshold (Ct)-value of <31 underwent a retrospective characterization via an in-house developed sequence analysis of the hemagglutinin-neuraminidase (HN) gene.
RESULTS: Between July and September 2022, 31 hematology patients were identified with PIV3. Although infection control measures were implemented, the outbreak persisted for nine weeks. Sequencing the HN gene of 27 PIV3 strains from 27 patients revealed that all outbreak strains formed a distinct cluster separate from the control strains, suggestive of a nosocomial transmission route.
CONCLUSIONS: Sequencing the HN gene of PIV3 strains in an outbreak setting enables outbreak strains to be distinguished from community strains. Early molecular characterization of PIV3 strains during an outbreak can serve as a tool in determining potential transmission routes. This, in turn, enables rapid implementation of targeted infection prevention measures, with the goal of minimizing the outbreak\'s duration and reducing associated morbidity and mortality.
METHODS: Patients were screened for respiratory viruses using multiplex-PCR. PIV3 positive samples with a cycle threshold (Ct)-value of <31 underwent a retrospective characterization via an in-house developed sequence analysis of the hemagglutinin-neuraminidase (HN) gene.
RESULTS: Between July and September 2022, 31 hematology patients were identified with PIV3. Although infection control measures were implemented, the outbreak persisted for nine weeks. Sequencing the HN gene of 27 PIV3 strains from 27 patients revealed that all outbreak strains formed a distinct cluster separate from the control strains, suggestive of a nosocomial transmission route.
CONCLUSIONS: Sequencing the HN gene of PIV3 strains in an outbreak setting enables outbreak strains to be distinguished from community strains. Early molecular characterization of PIV3 strains during an outbreak can serve as a tool in determining potential transmission routes. This, in turn, enables rapid implementation of targeted infection prevention measures, with the goal of minimizing the outbreak\'s duration and reducing associated morbidity and mortality.
摘要：
目的：血液病患者中3型副流感病毒（PIV3）的爆发与高发病率和高死亡率相关。迅速实施感染预防（IP）措施已被证明是控制该患者人群中PIV3暴发的最有效方法。最合适的IP措施可能因病毒传播模式而异，在大多数疫情中仍未被确认。我们描述了血液学患者中PIV3爆发的分子流行病学，以及一种新方法的开发，该方法可以区分爆发和社区菌株，从中可以推断出一次封闭的疫情。
方法：使用多重PCR对患者进行呼吸道病毒筛查。循环阈值(Ct)值<31的PIV3阳性样品通过血凝素-神经氨酸酶(HN)基因的内部开发的序列分析进行回顾性表征。
结果：在2022年7月至9月之间，31名血液病患者被确定为PIV3。尽管实施了感染控制措施，疫情持续了9周。对来自27例患者的27株PIV3菌株的HN基因进行测序显示，所有爆发菌株都与对照菌株形成了一个不同的簇，暗示了医院内的传播途径.
结论：在爆发环境中对PIV3菌株的HN基因进行测序可以将爆发菌株与社区菌株区分开来。PIV3菌株在爆发期间的早期分子表征可以作为确定潜在传播途径的工具。这个,反过来,能够快速实施有针对性的感染预防措施，目标是最大限度地减少疫情的持续时间，并降低相关的发病率和死亡率。
方法：使用多重PCR对患者进行呼吸道病毒筛查。循环阈值(Ct)值<31的PIV3阳性样品通过血凝素-神经氨酸酶(HN)基因的内部开发的序列分析进行回顾性表征。
结果：在2022年7月至9月之间，31名血液病患者被确定为PIV3。尽管实施了感染控制措施，疫情持续了9周。对来自27例患者的27株PIV3菌株的HN基因进行测序显示，所有爆发菌株都与对照菌株形成了一个不同的簇，暗示了医院内的传播途径.
结论：在爆发环境中对PIV3菌株的HN基因进行测序可以将爆发菌株与社区菌株区分开来。PIV3菌株在爆发期间的早期分子表征可以作为确定潜在传播途径的工具。这个,反过来,能够快速实施有针对性的感染预防措施，目标是最大限度地减少疫情的持续时间，并降低相关的发病率和死亡率。
