以噬菌体为指示病毒进行空气消毒效果评价的初步研究

A preliminary study on the evaluation of air disinfection effect using phage as indicator virus

目的以噬菌体Phi-X174为指示病毒,探索其用于空气病毒消毒效果评价的可行性。方法将噬菌体Phi-X174雾化到空气消毒舱,通过研究采样液、噬菌体悬液滴度、雾化时间、雾化量等关键参数,确定噬菌体气溶胶发生方式和采样方法,同时分析噬菌体气溶胶在不同时间点的自然沉降率,并使用初步建立的方法评价一种光触媒消毒技术对空气中噬菌体的杀灭效果。结果SM缓冲液对噬菌体Phi-X174的采集效率高于PBS;以滴度为3×108 pfu/mL的噬菌体悬液雾化1.5 mL,空气消毒舱内平均噬菌体浓度为4.25×106 pfu/m3,且重复性较好;噬菌体气溶胶在15、30、45和60 min的平均自然沉降率分别为28.40%、51.79%、68.61%和79.58%;该光触媒空气消毒技术高风量作用45 min或低风量作用60 min时,对噬菌体的平均杀灭率可达99.9%。结论用SM缓冲液进行气溶胶采样,以滴度为3×108 pfu/mL的噬菌体悬液1.5 mL作为雾化发生液,空气中噬菌体气溶胶在一定时间内浓度相对稳定,试验可重复性较好,采样效率较高,基本符合空气指示微生物的要求。

Objective To explore the feasibility of using phage Phi-X174 as indicator virus for evaluating the effect of air virus disinfection.Methods Phage Phi-X174 was nebulised into the air disinfection chamber.Referring to the requirements for the microbial counts of air indicators in China's air disinfection effect evaluation standards,the key parameters such as sampling solution,phage suspension titre,nebulisation time,nebulisation volume,etc were investigated to determine the generation mode and sampling method of phage aerosols,and the natural settling rates of phage aerosols at different time points were analyzed.Using the preliminarily established method,the killing effect of a photocatalytic disinfection technology on phage in air was evaluated.Results SM buffer was more efficient than PBS for phage Phi-X174 collection.When 1.5 mL of phage suspension with a titre of 3×108 pfu/mL was nebulized,the average phage concentration in the air disinfection chamber was 4.25×106 pfu/m3 with good reproducibility.The average natural settling rates of phage aerosols at 15 min,30 min,45 min and 60 min were 28.40%,51.79%,68.61%and 79.58%,respectively.The photocatalytic air disinfection technology was applied with high airflow for 45 min or low airflow for 60 min,and the average killing rate of phage could reach 99.9%.Conclusion Aerosol sampling with SM buffer and 1.5 mL of phage suspension with a titre of 3×108 pfu/mL as the nebulisation generating solution can achieve relatively stable concentration of phage aerosols in air for a certain period of time,with better test reproducibility,and higher sampling efficiency,etc.,which is basically in line with the requirements of air indicator microorganisms.