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Abstract Background Recent studies have focused on initial clinical and epidemiological characteristics of the coronavirus disease 2019 (COVID-19), which is the mainly revealing situation in Wuhan, Hubei. Aim This study aims to reveal more data on the epidemiological and clinical characteristics of COVID-19 patients outside of Wuhan, Zhejiang, China. Design This study was a retrospective case series. Methods Eighty-eight cases of laboratory-confirmed and three cases of clinically confirmed COVID-19 were admitted to five hospitals in Zhejiang province, China. Data were collected from 20 January 2020 to 11 February 2020. Results and discussion Of all 91 patients, 88 (96.70%) were laboratory-confirmed COVID-19 with throat swab samples that tested positive for SARS-Cov-2, three (3.30%) cases were clinically diagnosed. The median age of the patients was 50 (36.5–57) years, and female accounted for 59.34%. In this sample, 40 (43.96%) patients had contracted the disease from local cases, 31 (34.07%) patients had been to Wuhan/Hubei, eight (8.79%) patients had contacted with people from Wuhan, and 11 (12.09%) patients were diagnosed after having flown together in the same flight with no passenger that could later be identified as the source of infection. In particular within the city of Ningbo, 60.52% cases can be traced back to an event held in a temple. The most common symptoms were fever (71.43%), cough (60.44%) and fatigue (43.96%). The median of incubation period was 6 (interquartile range 3–8) days and the median time from the first visit to a doctor to the confirmed diagnosis was 1 (1–2) days. According to the chest computed tomography scans, 67.03% cases had bilateral pneumonia. Conclusions Social activity cluster, family cluster and flying alongside with persons already infected with COVID-19 were how people got infected with COVID-19 in Zhejiang.

Biofilms that form on roots, litter and soil particles typically contain multiple bacterial species. Currently, little is known about multispecies biofilm interactions and few studies have been based on environmental isolates. Here, the prevalence of synergistic effects in biofilm formation among seven different soil isolates, cocultured in combinations of four species, was investigated. We observed greater biofilm biomass production in 63% of the four-species culture combinations tested than in biofilm formed by single-species cultures, demonstrating a high prevalence of synergism in multispecies biofilm formation. One four-species consortium, composed of Stenotrophomonas rhizophila, Xanthomonas retroflexus, Microbacterium oxydans and Paenibacillus amylolyticus, exhibited strong synergy in biofilm formation and was selected for further study. Of the four strains, X. retroflexus was the only one capable of forming abundant biofilm in isolation, under the in vitro conditions investigated. In accordance, strain-specific quantitative PCR revealed that X. retroflexus was predominant within the four-species consortium (497% of total biofilm cell number). Despite low relative abundance of all the remaining strains, all were indispensable for the strong synergistic effect to occur within the four-species biofilm. Moreover, absolute individual strain cell numbers were significantly enhanced when compared with those of single-species biofilms, indicating that all the individual strains benefit from inclusion in the multispecies community. Our results show a high prevalence of synergy in biofilm formation in multispecies consortia isolated from a natural bacterial habitat and suggest that interspecific cooperation occurs.

Central to commercial fluid milk processing is the use of high temperature, short time (HTST) pasteurization to ensure the safety and quality of milk, and homogenization to prevent creaming of fat-containing milk. Ultra-high-temperature sterilization is also applied to milk and is typically used to extend the shelf life of refrigerated, specialty milk products or to provide shelf-stable milk. The structures of the milk proteins and lipids are affected by processing but little information is available on the effects of the individual processes or sequences of processes on digestibility. In this study, raw whole milk was subjected to homogenization, HTST pasteurization, and homogenization followed by HTST or UHT processing. Raw skim milk was subjected to the same heating regimens. In vitro gastrointestinal digestion using a fasting model was then used to detect the processing-induced changes in the proteins and lipids. Using sodium dodecyl sulfate-PAGE, gastric pepsin digestion of the milk samples showed rapid elimination of the casein and α-lactalbumin bands, persistence of the β-lactoglobulin bands, and appearance of casein and whey peptide bands. The bands for β-lactoglobulin were eliminated within the first 15min of intestinal pancreatin digestion. The remaining proteins and peptides of raw, HTST, and UHT skim samples were digested rapidly within the first 15min of intestinal digestion, but intestinal digestion of raw and HTST pasteurized whole milk showed some persistence of the peptides throughout digestion. The availability of more lipid droplets upon homogenization, with greater surface area available for interaction with the peptides, led to persistence of the smaller peptide bands and thus slower intestinal digestion when followed by HTST pasteurization but not by UHT processing, in which the denatured proteins may be more accessible to the digestive enzymes. Homogenization and heat processing also affected the ζ-potential and free fatty acid release during intestinal digestion. Stearic and oleic acids were broken down faster than other fatty acids due to their positions on the outside of the triglyceride molecule. Five different casein phosphopeptide sequences were observed after gastric digestion, and 31 sequences were found after intestinal digestion, with activities yet to be explored. Processing affects milk structure and thus digestion and is an important factor to consider in design of foods that affect health and nutrition.