Salmonellosis in two dairy herds associated with a sewage farm and water reclamation plant.

Two dairy herds, situated on a sewage farm, were monitored for the presence of salmonellas following outbreaks of Salmonella dublin infection. In addition an S. dublin control scheme, which involved examination of adult animals and calf vaccination, was instigated. During the period 1975-84, 12 salmonella serotypes and 10 phage types of S. typhimurium were isolated from the cattle and their environment although their presence was seldom associated with disease. Two adult S. dublin excreters were detected but it was concluded that none of the tests employed to examine the adult animals was sensitive enough. The prevalence of disease in the calves was low and although vaccination may have been beneficial it did not eradicate S. dublin infection. Thus S. dublin persisted in adults and calves during the 8-year period but its presence was seldom associated with disease. The results are discussed with regards the disease risk to animals from the agricultural use of sewage sludge and the public health aspects.     

Salmonella saint-paul infection in two dairy herds

An outbreak of salmonellosis due to Salmonella saint-paul in two dairy herds was first detected during routine examination of calves soon after calving; infection reached 100% amongst calves and up to 60% amongst milking cows. Excretion by cows continued for over 12 months and by calves for up to 18 months. The most important factor in controlling the spread of infection was reduction of environmental contamination by removal of carriers, prompt antibiotic treatment of sick calves and reduction in stocking densities.     

Salmonella saint-paul infection in two dairy herds.

An outbreak of salmonellosis due to Salmonella saint-paul in two dairy herds was first detected during routine examination of calves soon after calving; infection reached 100% amongst calves and up to 60% amongst milking cows. Excretion by cows continued for over 12 months and by calves for up to 18 months. The most important factor in controlling the spread of infection was reduction of environmental contamination by removal of carriers, prompt antibiotic treatment of sick calves and reduction in stocking densities.     

Comparative prevalence of tuberculosis in two dairy herds in India

Holstein Friesian cows and their crossbred progeny on a farm in northern India were tested for tuberculosis (TB) infection using a single intradermal tuberculin test. The results showed that the animals persistently harboured TB infection for periods of two to four years. The recent comparative intradermal tuberculin test revealed that at least five out of nine of these cattle reacted positively to bovine tuberculin purified protein derivative. A high (15.76%) prevalence rate resulted because none of the infected animals had been segregated or culled from the herd since the first incidence was detected in 1992. In contrast, another farm in western India that practiced segregation and culling was able to contain the level of prevalence of TB between 0.65% and 1.85%. These findings call for stricter regulations on the management of TB at farm, state and country level and a revision in the mode of breeding programmes adopted by farms.     

Illness in a community associated with an episode of water contamination with sewage.

Following an episode of water contamination with sewage in a rural Irish town, a community-wide survey of gastrointestinal-associated illness and health service utilization was conducted. Random sampling of households yielded residents who were surveyed using a self-administered questionnaire. Of 560 respondents from 167 (84%) households, equal proportions lived in areas known to have been exposed and unexposed to the contaminated water, although 65% of subjects reported using contaminated water. Sixty-one percent of subjects met the case definition. The most common symptoms among cases were abdominal cramps (80%), diarrhoea (75%), appetite loss (69%), nausea (68%) and tiredness (66%). Mean duration of illness was 7.4 days. Only 22% of cases attended their general practitioner. Drinking unboiled water from the exposed area was strongly associated with being a case. A substantial degree of community illness associated with exposure to contaminated water was observed. The episode ranks as one of the largest reported water-borne outbreaks causing gastrointestinal illness in recent times.     

Salmonellosis associated with pet turtles--Wisconsin and Wyoming, 2004

Salmonellosis associated with small pet turtles in the United States was a major public health concern in the 1970s. In 1975, the Food and Drug Administration (FDA) banned commercial distribution of small turtles (i.e., those with a carapace of <4 inches). The FDA ban prevents an estimated 100,000 cases of salmonellosis among children each year. However, a recent resurgence in the sale of small turtles has generated concern. In Wisconsin and Wyoming, at least six human cases of salmonellosis have been linked to such turtles. This report describes the investigation into those cases. The findings underscore the need for health and environmental officials to prevent illegal distribution of small turtles and consider patient contact with turtles when investigating salmonellosis cases.     

郑州市某污水处理厂尾水毒性评价

目的探讨郑州市某污水处理厂进出水的急性毒性和遗传毒性。方法采集该厂进水、二级出水和三级出水,利用发光细菌毒性测试法检测进出水的急性毒性,利用蚕豆根尖微核试验检测进出水的遗传毒性。结果进水、二级出水和三级出水对发光菌的抑光率分别为(33.96±7.51)%、(14.32±7.36)%、(7.24±5.58)%,二级出水和三级出水对发光菌的抑光率低于进水(F=12.159,P=0.008)。蚕豆根尖微核细胞率分别为(12.67±2.08)‰、(6.33±1.53)‰和(2.67±0.58)‰,污染程度分别为重度污染、轻度污染和基本无污染,二级出水及三级出水蚕豆根尖微核细胞率低于进水(F=56.850,P<0.001)。结论进水经处理后急性毒性及遗传毒性显著下降,但对环境仍具有一定的生态风险性。     

Salmonellosis associated with chicks and ducklings--Michigan and Missouri, Spring 1999

During the spring of 1999, outbreaks of salmonellosis associated with handling chicks and ducklings occurred in Michigan and Missouri. This report summarizes the epidemiologic information for the outbreaks and provides an overview of legislative efforts to control the distribution of chicks and ducklings. These outbreaks demonstrate that handling chicks and ducklings is a health risk, especially for children, and highlight the need for thorough handwashing after contact with chicks, ducklings, and other young fowl.     

Arcobacter cryaerophilus and thermophilic campylobacters in a sewage treatment plant in Italy: two secondary treatments compared.

Microaerophilic organisms were monitored in sewage effluent undergoing two secondary treatments: air and oxygen-activated sludge. The mean numbers of Arcobacter cryaerophilus and thermophilic campylobacters detected in incoming sewage were 5639/100 ml and 1720/100 ml respectively. Secondary treatment in air tanks reduced the population of A. cryaerophilus by 97.1% and of thermophilic campylobacters by 99.08%, whereas treatment in oxygen tanks reduced the bacteria 97.8% and 99.63% respectively, showing that oxygen-activated sludge treatment was more effective. Subsequent tertiary treatment with 2 p.p.m. chlorine dioxide evidenced the removal of A. cryaerophilus to 99.9% and eliminated thermophilic campylobacters. Campylobacter jejuni and C. coli constituted 54.1% and 45.9% of 74 thermophilic campylobacter strains isolated. In air-activated sludge effluent C. jejuni was found more often, thus appearing more sensitive to oxygen. The most probable number assay used for detection of campylobacters, blood medium for enrichment and blood-free medium for plating, also appeared to be fit for A. cryaerophilus, the high density of which in urban sewage may be due to inflows from slaughterhouses.     

The establishment of Enterobacteriaceae and Salmonella London in a new dairy farm environment

Salmonella spp. are important zoonotic pathogens in humans and animals. A longitudinal study was conducted at the Iowa State University's campus (at the Dairy/Animal Science Education and Discovery Facility) to observe change in Enterobacteriaceae (specifically Salmonella) before and after the placement of dairy livestock. To our knowledge, this is the first study that evaluated environmental changes of Gram-negative organisms in a new dairy farm environment. Environmental samples were taken using drag swabs and immediately processed in the laboratory using phenotypic methods (replica plating, the BBL Crystal Identification System for enteric/nonfermenter organisms?, and plating on specialized media/broths). Genotypic methods were also used (BAX PCR? and pulsed-field gel electrophoresis). Organisms identified as Salmonella were sent to the National Veterinary Services Laboratory (Ames, IA) for confirmatory serotyping. Resistance to antibiotics (ampicillin, nalidixic acid, and tetracycline) was determined by replica plating of Enterobacteriaceae and Salmonella isolates using the guidelines of the National Antimicrobial Resistance Monitoring System and Clinical and Laboratory Standards Institute. The microflora of Enterobacteriaceae changed as cattle were introduced and as time progressed. Additionally, multidrug-resistant isolates began to appear immediately after cattle were introduced (multidrug-resistant isolates were rare prior to introduction of livestock). Variables such as temperature and humidity did not affect the proliferation of bacterial organisms. Seventeen Salmonella isolates were identified as Salmonella London and three isolates as Salmonella Montevideo. Based on pulsed-field gel electrophoresis-generated dendrograms, it is likely that 17 Salmonella London isolates and 3 Salmonella Montevideo isolates are clonal.     

Coxiella burnetii in sewage water at sewage water treatment plants in a Q fever epidemic area

During 2007–2010, over 4000 persons in The Netherlands contracted Q-fever, a zoonosis caused by the bacterium Coxiella burnetii. Goats and sheep are the main reservoir of C. burnetti and infected animals shed the bacterium with their urine, faeces and birth products. Human infections may occur through direct contact with infected animals, or through inhalation of contaminated dust particles or aerosols. Discharge of waste water from Q fever contaminated goat farms may result in the presence of C. burnetii in sewage water and aerosols at sewage water treatment plants (SWTPs) which may pose a health risk for workers or neighbouring residents. The objectives of this study were to determine the presence of C. burnetii at SWTPs and to optimize available detection methods. In March–July 2011, sewage influent and aeration tank samples from four SWTPs receiving discharge from Q fever positive goat farms were examined by using a multiplex real-time PCR detecting C. burnetii DNA by targeting IS1111 and com1 genes. Influent (44%; n = 16/36) and active sludge (36%; n = 13/36) samples were positive with low C. burnetii DNA content. Percentage positive samples per SWTP were 28–61%. Positive samples were most frequent in March 2011 and least frequent in May 2011. The presence of C. burnetii DNA in sewage water samples suggests that SWTPs receiving waste water from Q fever contaminated goat farms may contribute to the spread of C. burnetii to the environment. The low levels of C. burnetii DNA in sewage water during the decline of the Q fever outbreak in The Netherlands in 2011 indicate a low health risk for SWTP workers and residents.     

某奶牛养殖场职工职业健康检查结果分析

对某奶牛养殖场227名在岗职工的职业健康检查资料进行统计分析及职业卫生学调查.有168名受检职工(74.01％)出现一项或多项体检项目异常,其中腹部超声检查异常率最高(38.33％),其次为血常规、血压、血沉等.该企业现有的45例职业性布鲁菌病患者,73.33％存在关节疼痛的症状.提示企业应重视职业防护,定期进行职业健...     

郑州市某污水处理厂新技术出水急性毒性实验研究

目的研究郑州市某污水处理厂新技术出水急性毒性,为城市污水回用安全评价提供科学依据。方法按《化学品毒理学评价程序和试验方法》(GBZ/T240—2011)对深度处理出水进行急性经口、经皮、眼刺激、皮肤刺激和皮肤致敏实验。结果新技术出水对小鼠急性经口LD50雌性为6810 mg/kg BW,属于实际无毒级;雄性为4220 mg/kg BW,属于低毒级;大鼠急性经皮LD50雌性为6810 mg/kg BW,雄性为5620 mg/kg BW,均属于实际无毒级。对兔眼角膜、结膜均有不同程度损伤作用,眼刺激积分指数(IAOI)为28,眼刺激平均指数(MIOI)7 d后小于20,属于中度刺激性;对豚鼠皮肤刺激积分均值为0,刺激强度为无刺激性;对豚鼠皮肤致敏积分均值为0,为无致敏性。结论新技术出水在回用过程中不可经口摄入,避免眼睛接触,经皮接触无刺激和致敏作用。     

Diarrheal diseases in children from a water reclamation site in Mexico city

This study was conducted to assess the risk of enteric diseases among children living in a water reclamation area in Mexico City. A geographic information system was used to define eligible wells and surrounding homesteads. Sixty-five water samples from five wells were tested for fecal coliform bacteria per 100 mL (FC/100 mL) during visits to 750 eligible households; caretakers only in those dwellings with children under 5 years old were interviewed throughout repeated cross-sectional surveys, conducted during 1999-2000. Data on diarrheal diseases were obtained from 761 children during the rainy season and 732 children during the dry season; their guardians also provided information on drinking water supply, sanitation, and socioeconomic variables. The presence of indicator organisms in groundwater samples pointed to fecal pollution; bacterial indicators, however, did not predict the health risk. The rates of diarrhea were 10.7% in the dry season and 11.8% in the rainy season. Children 1 year old showed the highest rate of diarrhea during the dry season [odds ratio (OR) = 2.1 with 95% confidence interval (CI), 0.99-4.71], particularly those from households perceiving unpleasant taste of tap water (OR, 1.7; 95% CI, 0.97-2.92) and consuming vegetables washed only with water (OR, 2.2; 95% CI, 1.10-4.39). Lower risk was observed in individuals enjoying full-day water supply (OR, 0.5; 95% CI, 0.27-0.86) and a flushing toilet (OR, 0.3; 95% CI, 0.16-0.67), as well as those storing water in covered receptacles (OR, 0.3; 95% CI, 0.15-0.80). Rainy season data suggested that children from households perceiving a color to their water had a higher rate of diarrhea than did those without such complaint (OR, 1.8; 95% CI, 0.93-3.67); recent consumption of food sold by street vendors was also a significant risk factor (OR, 1.6; 95% CI, 0.98-2.87). Groundwater is at risk of contamination, as indicated by the presence of FC/100 mL. The endemic pattern of diarrhea, however, reflects mostly inadequate housing, sanitation, and water-related practices. Health protection policy must be discussed.     

Spatial and spatio-temporal analysis of Salmonella infection in dairy herds in England and Wales

Using data from a cohort study conducted by the Veterinary Laboratories Agency (VLA), evidence of spatial clustering at distances up to 30 km was found for S. Agama and S. Dublin (P values of 0.001) and borderline evidence was found for spatial clustering of S. Typhimurium (P=0.077). The evolution of infection status of study farms over time was modelled using a Markov Chain model with transition probabilities describing changes in status at each of four visits, allowing for the effect of sampling visit. The degree of geographical clustering of infection, having allowed for temporal effects, was assessed by comparing the residual deviance from a model including a measure of recent neighbourhood infection levels with one excluding this variable. The number of cases arising within a defined distance and time period of an index case was higher than expected. This provides evidence for spatial and spatio-temporal clustering, which suggests either a contagious process (e.g. through direct or indirect farm-to-farm transmission) or geographically localized environmental and/or farm factors which increase the risk of infection. The results emphasize the different epidemiology of the three Salmonella serovars investigated.