A comparative study on environmental surveillance of enterovirus:Using a two-phase separation method and a filtration method with a mixed cellulose ester(MCE)membrane

This study aimed to compare the sensitivity of two-phase separation and the filtration method using a mixed cellulose ester(MCE)membrane to detect enteroviruses in sewage samples.From December 2015 to July 2016,four domestic sewage samples(1 L/sample)were collected monthly from the Guangzhou Liede Sewage Treatment Plant,and each sewage sample was divided into two aliquots(500 mL).The sewage sample was concentrated using the two-phase separation and the filtration method using an MCE membrane,and the treated solutions were inoculated into cells for enterovirus isolation.Polymerase chain reaction amplification,VP1 sequencing,and enterovirus molecular typing were performed on the positive isolates.The detection rates of poliovirus(PV)and non-polio enterovirus(NPEV)obtained using the filtration method using an MCE membrane were higher than those using the two-phase separation method.McNemar's test showed that the detection rates of PV,NPEV,type 1 Sabin-like(SL1),type 2 Sabin-like(SL2),and type 3 Sabin-like(SL3)strain were not statistically significant(P>0.05).In Guangdong Province,China,the detection rates for PV and NPEV were 53.13%and 62.50%(20/32),respectively.Twenty-seven PVs were isolated,three highly variable strains of the type 1 vaccine,with seven nucleotide substitutions in the VP1 region,compared with the type 1 Sabin strains.Eighty-seven strains of NPEV were isolated and nine serotypes were identified,among which coxsackievirus B3(CVB3),echovirus 6(E6),and echovirus 11(E11)were the dominant strains.The filtration method using an MCE membrane is more sensitive than two-phase separation and can be used as a robust,sensitive,and cost-effective method to isolate enteroviruses from sewage.

Enhanced environmental surveillance for avian influenza A/H5,H7 and H9 viruses in Guangxi,China,2017-2019

We conducted environmental surveillance to detect avian influenza viruses circulating at live poultry markets(LPMs)and poultry farms in Guangxi Autonomous Region,China,where near the China-Vietnam border.From November through April 2017-2018 and 2018-2019,we collected environmental samples from 14 LPMs,4 poultry farms,and 5 households with backyard poultry in two counties of Guangxi and tested for avian influenza A,H5,H7,and H9 by real-time reverse transcription-polymerase chain reaction(rRT-PCR).In addition,we conducted four cross-sectional questionnaire surveys among stall owners on biosecurity practices in LPMs of two study sites.Among 16,713 environmental specimens collected and tested,the median weekly positive rate for avian influenza A was 53.6%(range=33.5%-66.0%),including 25.2%for H9,4.9%for H5,and 21.2%for other avian influenza viruses A subtypes,whereas a total of two H7 positive samples were detected.Among the 189 LPM stalls investigated,most stall owners(73.0%)sold chickens and ducks.Therefore,continued surveillance of the avian influenza virus is necessary for detecting and responding to emerging trends in avian influenza virus epidemiology.

Environment surveillance of filamentous fungi in two tertiary care hospitals in China

Background Invasive fungal infections have constituted an increasingly important cause of morbidity and mortality in immunocompromised patients. In this study, a surveillance project was conducted in three different intensive care units of two large tertiary hospitals in China. Methods A one-year surveillance project was conducted in two tertiary hospitals which located in northern China and southwest China respectively. Air, surfaces and tap water were sampled twice a month in a central intensive care unit, a bone marrow transplant unit, a neurosurgery intensive care unit and a live transplant department. Environmental conditions such as humidity, temperature and events taking place, for example the present of the visitors, healthcare staff and cleaning crew were also recorded at the time of sampling. Results The air fungal load was 91.94 cfu/m3 and 71.02 cfu/m3 in the southwest China hospital and the northern China hospital respectively. The five most prevalent fungi collected from air and surfaces were Penicillium spp., Cladospcrium spp., Altemaria spp., Aspergillus spp. and Saccharomyces spp. in the southwest China hospital, meanwhile Penicillium spp., Fusarium spp., Aspergillus spp., Alternaria spp. and Cladospcrium spp. in the northern China hospital. The least contaminated department was intensive care units, and the heaviest contaminated department was neurosurgery intensive care unit. Seventy-three percent of all surfaces examined in the northern China hospital and eighty-six percent in the southwest China hospital yielded fungi. Fifty-four percent of water samples from the northern China hospital and forty-nine percent from the southwest China hospital yielded fungi. Conclusions These findings suggested that the fungus exist in the environment of the hospital including air, surface and water. Air and surface fungal load fluctuated over the year. Air fungal load was lower in winter and higher in summer and autumn, but seldom exceeded acceptable level. The higher values were created during May to August in the northern China hospital and May to June and September to October in the southwest China hospital. A correlation between air fungal load and humidity, as well as personnel was observed.