城市污水中人类星状病毒的检测及变化规律

Detection and Distribution of Human Astrovirus in Domestic Wastewater

人类星状病毒是典型的水媒病毒,可引起腹泻等疾病.为了明确污水中人类星状病毒的分布及去除规律,利用常规PCR和定量PCR方法对西安市3个污水处理厂的进水和出水进行了为期1 a的监测;采用特异性引物,确立了人类星状病毒在环境水体中的定性PCR和荧光定量PCR的检测方法.结果表明,人类星状病毒在进水和未消毒二级出水中呈较高的阳性率,分别为91.5%和36.6%.经过核苷酸测序鉴定,人类星状病毒的主要血清型为HAst V-1和HAst V-4.人类星状病毒在进水和未消毒二级出水中的平均浓度分别为1.47×104和1.03×103copies/mL,污水处理厂对人类星状病毒的去除率为93.15%.污水处理厂进水中人类星状病毒浓度呈季节性变化,春季和冬季较高,夏季和秋季较低,这一分布规律与该地区历年人类星状病毒的流行规律相似.

One of the most important waterborne viral pathogens,human astrovirus（ HAst V）,can cause acute diarrhea,and was believed to be present in environmental waters in China. In order to investigate the distribution and removal of human astrovirus in domestic wastewater,the conventional PCR method combined with a nucleic acid sequencing technique and real-time PCR method with specific primers were used to detect the human astrovirus in the influent and the effluent before disinfections of three wastewater treatment plants. A seroepidemiological survey and semimonthly quantitative surveillance of the human astrovirus for one year were achieved. The results showed that the positive ratios of human astrovirus in the influent and effluent before disinfection were 91. 5% and 36. 6%,respectively. The serotypes of human astrovirus in the studied area were mainly identified as HAst V-1 and HAst V-4,based on the sequencing results of the nucleic acids. The concentrations of human astrovirus in the influent of WWTPs were in the range of 10^2-10^5 copies/mL,with a mean value of 1. 47 × 10^4copies/mL. The concentration of human astrovirus in the effluent before disinfection ranged from 10^1to 10^4 copies/mL,with mean of 1. 03 × 10^3 copies/mL,indicating a 93. 15% removal of human astrovirus by the conventional secondary treatment process. The distribution of the human astrovirus in the influent showed seasonal variation,with the concentrations of human astrovirus being high in spring and winter,but low in summer and autumn. The distribution was similar with the circumstances of human astrovirus epidemiology in the studied area,from the aspect of clinical infection. Further studies should be conducted to determine the relationship between occurrence of human astrovirus in domestic wastewater and epidemiology of that in clinical infection.