The prevalence of Salmonella enteritidis and other Salmonella spp. among Canadian registered commercial layer flocks

A survey was conducted to estimate the prevalence of Salmonella enteritidis and other salmonellas among Canadian commercial egg producing flocks. Environmental (faecal and eggbelt) samples from 152 of 295 (52.9%) randomly selected flocks were contaminated with salmonellas. Thirty-five different salmonella serovars were isolated. Eggbelt samples were more often contaminated with salmonellas than faecal samples (25.7 v. 10.1%). The most prevalent serovars were S. heidelberg, S. infantis, S. hadar, and S. schwarzengrund; they were isolated from samples of 59/295 (20%), 18/295 (6.1%), 17/295 (5.8%), and 15/295 (5.1%) flocks, respectively. Feed samples of 21/295 (7.2%) flocks were contaminated with salmonellas. Salmonella enteritidis was isolated from the environmental samples of 8/295 (2.7%) flocks. Salmonella enteritidis phage type (PT) 8 was isolated from 5 flocks, PT 13a from 2 flocks, and PT 13 from 1 flock.     

Evaluation of a serological Salmonella mix-ELISA for poultry used in a national surveillance programme

A Mix-ELISA using lipopolysaccharide antigens from Salmonella enterica serotype Enteritidis and Typhimurium was evaluated using samples collected over time in the Danish salmonella surveillance programme for poultry. Serological samples (n = 42,813) taken from broiler-breeder flocks after a year of bacteriological monitoring with negative results were used for calculating the flock and individual test specificities, which were 0.997 and 0.999, respectively. Layer flocks from the table egg sector were used for calculation of positive predictive values. In the survey, flocks were examined for salmonella by Mix-ELISA and by faecal culture, and in case of a positive result in either of these a repeated, serological testing was performed, and 60 animals were organ-cultured. If one of these samplings was positive, the flock was declared salmonella infected. In a period of 3 months, 35 flocks were found to be positive in the routine samples. Of these, 32 were serologically positive, 2 both serologically and faecally positive and 1 flock only faecally positive. For flocks serologically positive in the surveillance programme, a positive-predictive value of 0.62 for organ culture positivity was found, and while considering serological follow-up samples, the value was 0.95.     

Risk factors for Salmonella prevalence in laying-hen farms in Japan

Human salmonellosis cases, particularly those caused by Salmonella Enteritidis, have been closely linked to egg consumption. This epidemiological survey was conducted to determine the baseline Salmonella prevalence and identify the risk factors for Salmonella prevalence in laying-hen farms in Japan. Caecal excrement samples and dust samples were obtained from 400 flocks in 338 laying-hen farms. Salmonella was identified in 20.7% of the farms and 19.5% of the flocks. The prevalence of Salmonella was significantly higher in flocks reared in windowless houses than in those reared in open houses. In addition, the risk of Salmonella presence was significantly higher when the windowless house farms implemented induced moulting or in-line egg processing. Efforts to reduce human salmonellosis in Japan should continue to focus on the establishment of control measures in laying-hen farms, especially those with windowless houses implementing induced moulting and equipped with in-line egg processing.     

Quantitative examination of Salmonella spp. in the lairage environment of a pig abattoir

One of the initial sources of Salmonella spp. and other bacterial pathogens at the abattoir is the carrier pig. In the absence of effective cleaning and disinfection measures, such animals may contaminate the lairage environment, which may act as a significant source of infection for incoming non-infected animals. The objectives of this study were to quantify the levels of Salmonella spp. in the lairage of a large pig abattoir and to compare the effect on environmental contamination levels with Salmonella spp. of the cleaning procedures carried out daily to those undertaken weekly. A total of 359 swabs were collected from lairage pen floors at three timepoints throughout the course of two slaughter days. All samples were analyzed quantitatively. On day 1, Monday, following weekly cleaning and disinfection, 6% of the 179 floor swabs taken were positive for Salmonella spp. On day 2, Thursday, at the end of the slaughter week, when lairage pens were subjected to high-pressure cold water washing between batches of pigs, 44% of the 180 floor swabs taken were positive for Salmonella spp. Quantitative analysis revealed that the median numbers of salmonellae detected following weekly cleaning and disinfection were approximately 1.8 organisms/100 cm(2). The numbers of salmonellae detected on day 2 were approximately 8 organisms/100 cm(2). The most prevalent serotype isolated in this study was S. Typhimurium (42%). Phage types DT12, DT104b, and U302 comprised the majority of phage types identified. These results highlight the need to develop effective intervention measures to control the spread of Salmonella spp. in the preslaughter environment.     

Chagas' disease: risk factors for house infestation by Triatoma dimidiata, the major vector of Trypanosoma cruzi in Costa Rica

The reduction of domiciliary infestation by insect vectors, the key to controlling Chagas' disease, depends on identification of housing features associated with infestation. In this study, log-linear modeling was used to reanalyze data collected in 1964-1968 from 371 houses on characteristics potentially associated with infestation by the vector Triatoma dimidiata in a Costa Rican town with endemic Chagas' disease. A possible increased risk of infestation was observed for houses with a dirt floor (as compared with houses with another floor type) and for houses in poor sanitary condition (as compared with houses in good sanitary condition). A new risk factor for house infestation, the presence of roof tiles, was identified; the odds of infestation for houses with a tile roof were 2.4 times greater than the odds for houses with a galvanized metal roof. This significantly increased risk is probably due to the harboring of T. dimidiata in stacks of spare tiles next to house walls rather than to the tile roofs themselves.     

Salmonella enteritidis phage type 4 from the contents of intact eggs: a study involving naturally infected hens

Two small flocks of egg-laying hens, naturally infected with Salmonella enteritidis, were housed in individual cages so that their eggs could be identified. During a longitudinal study where the contents of 1,119 eggs were examined, 11 were positive for S. enteritidis. One isolate was phage type (PT) 33 the others were PT4. The production of infected eggs was clustered though intermittent. The positive eggs, which were produced by 10 of the 35 hens, were all found to contain fewer than 10 salmonellas. Some birds were also apparently carrying S. hadar PT14 as this organism was isolated from the contents of six cracked eggs.     

An outbreak of echovirus 11 in a children's home

An outbreak of echovirus 11 infection was observed in a children's home that housed 16 children. Nine children younger than 1 year shared a large room on the first floor, which contained a large basin. Three of them presented with aseptic meningitis with CSF and stool samples positive for echovirus 11. The other six infants who shared the room were asymptomatic but their stools were positive for echovirus 11. Seven infants aged 1-2 years stayed on the second floor and were asymptomatic. One of them had positive stool culture for echovirus 11. No virus was isolated from stool samples taken from the 26 staff members. However, serology was suggestive for recent echovirus 11 infection in seven asymptomatic staff members. All seven worked either exclusively on the first floor or alternately on both floors. Our survey demonstrated that echovirus 11 may spread very efficiently in children's homes. The rate of meningitis in the infected infants was 30% while all the recently infected adults were asymptomatic.     

Indoor radon in the region of Brussels

The indoor radon (222Rn) concentration has been measured by charcoal detectors in 278 buildings in the region of Brussels, Belgium. The correlation with the nature of the subsoil can be studied in detail thanks to the available geotechnical map. With a geometrical mean indoor radon concentration of 19 Bq m(-3), Brussels can be considered as generally unaffected by the radon problem. No value higher than 400 Bq m(-3) (the EU reference level for existing houses) was measured in an occupied room. However, two factors that may enhance the risk are identified: the absence of a basement or a ventilated crawl space, and the presence of loess, under the house. About one third of the houses without basements or ventilated crawl spaces built on loess show an indoor radon concentration above 200 Bq m(-3) (the EU reference level for new houses).     

2011-2012年杭州市肠道沙门菌临床分离株的分子型别分析

目的研究2011-2012年杭州市肠道沙门菌临床分离株的型别,了解本地菌株分子流行病学特征。方法对66株肠道沙门菌临床分离株进行血清分型和多位点序列分型(MLST)。对其中主要血清型:鼠伤寒、甲型副伤寒、萨雷甲尼和肠炎沙门菌菌株进行脉冲场凝胶电泳(PFGE)分型。结果分布于21个血清型的66株沙门菌分成26个ST型别。发现一株纽波特沙门菌为新型ST1690。菌株血清型与MLST型别数据库中所对应的血清型符合率为100.00%。9株甲型副伤寒沙门菌的PFGE带型完全一致(P7型),与先前杭州流行菌株有差异(P1-P6型)。6株肠炎沙门菌分成4个PFGE型,型间最小相似性为92.70%。13株鼠伤寒沙门菌分为11个PFGE型,型间最小相似性为71.70%。7株萨雷甲尼沙门菌分成4个PFGE型别,型间最小相似性为91.00%。结论近年杭州腹泻病人中流行的肠道沙门菌菌株主要血清型为鼠伤寒、甲型副伤寒、萨雷甲尼和肠炎等。甲型副伤寒沙门菌菌株在杭州出现了新PFGE型别。MLST数据可以对沙门菌血清学鉴定提供一定的帮助。     

Introducing Alphitobius diaperinus, (Insecta: Tenebrionidae) as a New Intermediate Host of Hadjelia truncata (Nematoda)

Background

Hadjelia truncata is a nematode that causes lesions in the gizzard lining of pigeons, which may even lead to death. The aim of this study was to introduce Alphitobius diaperinus as a new intermediate host for Hadjelia truncata.

Methods

H. truncata infection was identified in a pigeon flock in Ahvaz City, Khuzestan Province, Iran by performing fecal examination and autopsy. Adult and larval stages of beetles were collected from the litter of pigeon houses, and identified morphologically. The beetle larvae were cultured in a medium, containing feces of the infected pigeons. Nematode larval stages from naturally and experimentally (culturally) infected adult beetles were fed to two groups of pigeons

Results

The collected beetles were identified as Alphitobius diaperinus. Average length and width of the adult beetles were 6.31 mm and 2.88 mm respectively. Infection rates of naturally and experimentally infected beetles with larval stages of the nematode were 66.2% and 45.1% respectively. The adult nematodes collected from gizzards of experimentally infected pigeons were identified as H. truncata. Nematode infection rates in pigeons after feeding the infective larvae collected from naturally and experimentally infected beetles were 44.7% and 32.5% respectively.

Conclusion

A. diaperinus can serve as a natural intermediate host for H. truncata.     

The prevalence of Salmonella enteritidis and other Salmonella sp. among Canadian registered commercial chicken broiler flocks

A nation-wide survey was conducted to estimate the prevalence of Salmonella enteritidis and other salmonellas among Canadian commercial broiler flocks. Environmental (litter and/or water) samples from 226 of 294 (76.9%) randomly selected flocks were contaminated with salmonellas. Litter samples were more often contaminated with salmonellas than water samples (47.4 v. 12.3%). Fifty different salmonella serovars were isolated. The most prevalent serovars were S. hadar, S. infantis, and S. schwarzengrund; they were isolated from samples of 98/294 (33.3%), 26/294 (8.8%), and 21/294 (7.1%) flocks, respectively. Feed samples of 39/290 (13.4%) flocks were contaminated with salmonellas. Salmonella enteritidis was isolated from the environmental samples of 9/294 (3.1%) flocks. Salmonella enteritidis phage type (PT) 8 was isolated from seven flocks, and PT 13a from two flocks.     

Salmonella and Shigella gastroenteritis at a public teaching hospital in Nairobi, Kenya.

OBJECTIVE: To measure the proportion of nosocomial diarrhea cases associated with Salmonella and Shigella species. DESIGN: Prospective 6-month survey. SETTING: Tertiary care center in a developing country. PATIENTS: Pediatric and adult patients admitted with the previous 24 hours and all consenting adult or pediatric medical patients with nosocomial diarrhea. OUTCOME MEASURES: Prevalence of Salmonella and Shigella species isolated from rectal swabs at admission and among subjects with nosocomial diarrhea. RESULTS: Salmonella species and Shigella species were isolated from 3.0% and 2.5%, respectively, of 667 patients screened on admission. All admission Salmonella isolates were identified in children under 13 years of age; Shigella prevalence was similar for children and adults. Children with Salmonella at admission were significantly older and more likely to have diarrhea, fever, and some indicators of malnutrition than those from whom Salmonella was not isolated. Salmonella and Shigella were isolated from rectal cultures in 36 (10%) and 9 (2.5%) of 360 nosocomial gastroenteritis cases, respectively. Nosocomial cases occurred equally in adults and children. In adults, nosocomial Salmonella acquisition was associated with sharing a room with a diarrhea patient and previous institutionalization. In children, it was associated with recent antimicrobial therapy, crowding at home, and age between 6 months and 6 years. Nine (41%) of 22 nosocomial Salmonella cases in adults occurred in patients with human immunodeficiency virus-type 1 (HIV-1) infection, while none of 79 HIV-1-positive patients had Salmonella isolated at admission. CONCLUSIONS: Salmonella is a frequent cause of nosocomial gastroenteritis in this tertiary care institution in a developing country. Risk factors appear to differ for children and adults, and HIV-1-infected subjects may be at increased risk of acquisition. Control measures feasible for the limited resources available to such institutions require evaluation.     

鼠伤寒沙门菌生物学分型方法在流行病学调查和监测中的应用

为探索用简便有效的手段对鼠伤寒沙门菌感染进行调查监测，采用英国学者Ｄｕｇｕｉｄ的鼠伤寒沙门菌生物学分型方法，应用于医院天津监测、病例追踪、食物中毒调查。结果：从医院感染患儿分离菌株的主要生物型与医院环境污染、医务人员携带菌株的生物型分布相似；截瘫患者尿中菌株与从其家庭环境和妻子手上分离菌株生物型别一致；从食物中毒者和乘彩中分离菌株的生物型别与鸭子携带菌株主要生物型别一致。结论：患儿医院感染是由于病     

Mycobacterium avium Subsp. avium and Salmonella enterica serotype Typhimurium var. Copenhagen phage type DT2 in pigeons

We report on a coinfection of Mycobacterium avium subsp. avium and Salmonella enterica serotype Typhimurium var. Copenhagen phage type DT2 in pigeons from one flock, from which squabs were occasionally consumed by humans. Triplex quantitative real-time PCR and culture methods were used for M. a. avium detection in livers and culture method was used for the detection of Salmonella sp. in samples of liver and caecum of 33 examined birds. M. a. avium was detected in a total of 31 (93.9%) and Salmonella Typhimurium in a total of 11 (33.3%) pigeons. Coinfection with both pathogens was found in 10 (30.3%), infection with Salmonella Typhimurium alone in 1 (3.0%), and infection with M. a. avium alone in 21 (63.7%) pigeons. Neither pathogen was detected in one pigeon. There was no difference in clinical symptoms exhibited by pigeons infected by M. a. avium and/or Salmonella Typhimurium. All Salmonella Typhimurium isolates were sensitive to all 15 antimicrobials tested. According to these results we emphasize good heat treatment of consumed squabs.     

Comparison of Salmonella species recovered from Irish liquid milk production holdings with temporal clinical veterinary isolates

The presence of microbiological hazards in foodstuffs including, Salmonella, form a major source of food-borne diseases in humans. In-line milk filters from 97 liquid milk production holdings in Cork, the largest dairy region in Ireland, were surveyed for the presence of Salmonella species at herd level over a 2-year period (September 2001-September 2003). Each dairy farm was visited 6 times at 4 monthly intervals (denoted by cycles A-F). Six of the 97 herds (6%) were positive. Ten isolates were detected based on culture methods. These included five (5%) Salmonella Typhimurium DT104, 4 (4%) Salmonella Dublin, and 1 (1%) Salmonella Agona from a total of 556 filters. During cycle C, in addition to the milk filters, a bulk tank milk (BTM) sample was procured from each dairy holding and analysed but no Salmonella were isolated. For comparison purposes a further 26 temporal veterinary clinical isolates (21 S. Typhimurium of varying phage type, and 5 S. Dublin) were procured from the Cork Veterinary Clinical Diagnostic Laboratory, Cork. The study collection showed resistance to one or more antimicrobial agents. During the study, Salmonella spp. were isolated from five of the herds prior to any clinical signs in the farm animals. Pulsed-field gel electrophoresis (PFGE) profiles indicated clonality among the isolates pre- and post-clinical illness. A phenotypic and genotypic database for Salmonella spp. has been developed and used for comparative purposes.     

Epidemiology of Campylobacter spp. at two Dutch broiler farms.

Broiler flocks on two Dutch poultry farms were screened weekly for the presence of campylobacter in fresh caecal droppings during eight consecutive production cycles. Hatchery and fresh litter samples were taken at the start of each new cycle. Water, feed, insects, and faeces of domestic animals, present on the farms were also included in the sampling. Penner serotyping of isolates was used to identify epidemiological factors that contribute to campylobacter colonization in the broiler flocks. Generally, broiler flocks became colonized with campylobacter at about 3-4 weeks of age with isolation percentages of 100%, and stayed colonized up to slaughter. A similar pattern of serotypes was found within the various broiler houses on one farm during one production cycle. New flocks generally showed also a new pattern of serotypes. Most serotypes isolated from the laying hens, pigs, sheep and cattle were different from those isolated from the broilers at the same time. Campylobacter serotypes from darkling beetles inside the broiler houses were identical to the ones isolated from the broilers. No campylobacter was isolated from any of the hatchery, water, feed or fresh litter samples. Conclusive evidence of transmission routes was not found, but results certainly point towards horizontal transmission from the environment. Horizontal transmission from one broiler flock to the next one via a persistent contamination within the broiler house, as well as vertical transmission from breeder flocks via the hatchery to progeny, did not seem to be very likely.     

2013年江苏省食源性非伤寒沙门菌疾病负担研究

目的估计江苏省食源性非伤寒沙门菌发病情况及疾病负担。方法根据全省监测点哨点医院主动监测和社区人群急性胃肠炎入户调查,采用疾病负担研究金字塔法,计算食源性非伤寒沙门菌疾病负担。结果 2013年采集感染性腹泻标本6 775例,检出非伤寒沙门菌113株,检出率为1.67%;入户调查10 802人,急性胃肠炎月发病率为4.43%,年发病率为0.59次/人年,病例就诊率为45.09%,标本采集率为45.37%;推算出江苏省2013年食源性非伤寒沙门菌疾病负担是454 614例病例。结论非伤寒沙门菌是重要的食源性致病菌,可造成较重的疾病负担。     

Oral immunisation of laying hens with the live vaccine strains of TAD Salmonella vac E and TAD Salmonella vac T reduces internal egg contamination with Salmonella Enteritidis

Eggs are a major source of human infections with Salmonella. Therefore controlling egg contamination in laying hen flocks is one of the main targets for control programmes. A study was carried out to assess the effect of oral vaccination with TAD Salmonella vac E, TAD Salmonella vac T and with both vaccines TAD Salmonella vac E and TAD Salmonella vac T, on colonization of the reproductive tract and internal egg contamination of laying hens with Salmonella Enteritidis. Three groups of 30 laying hens were vaccinated at 1 day, 6 weeks and 16 weeks of age with either one of the vaccine strains, or a combination of both vaccine strains, while a fourth group was left unvaccinated. At 24 weeks of age, the birds were intravenously challenged with 0.5 ml containing 5 x 10(7)cfu Salmonella Enteritidis PT4 S1400/94. The number of oviducts from which Salmonella was isolated, was significantly lower in the vaccinated than in the non-vaccinated hens at 3 weeks post-challenge. Significantly less egg contents were Salmonella positive in the birds vaccinated with TAD Salmonella vac E or TAD Salmonella vac T (12/105 batches of eggs in both groups) than in the unvaccinated birds (28/105 batches of eggs). Internal egg contamination in the hens vaccinated with both TAD Salmonella vac E and TAD Salmonella vac T was even more reduced, as over the whole experiment, only one batch of eggs was positive. In conclusion, these data indicate that vaccination of laying hens with these live vaccines could be considered as a valuable tool in controlling internal egg contamination.     

Life-threatening infantile diarrhea from fluoroquinolone-resistant Salmonella enterica typhimurium with mutations in both gyrA and parC

Salmonella Typhimurium DT12, isolated from a 35-day-old infant with diarrhea, was highly resistant to ampicillin, tetracycline, chloramphenicol, streptomycin, gentamycin, sulfamethoxazole/trimethoprim, nalidixic acid, and fluoroquinolones. The patient responded to antibiotic therapy with fosfomycin. Multidrug-resistance may become prevalent in Salmonella infections in Japan, as shown in this first case of a patient infected with fluoroquinolone-resistant Salmonella.     

扬州市2005—2007年监管场所羁押人员HIV监测分析

目的了解扬州市监管场所中羁押人员HIV感染状况，以防止艾滋病在监管场所中传播与蔓延。方法定期对扬州市所有监管场所羁押人员进行调查，按照统一调查表填写，录入Excel并统计分析；采集静脉血5ml，用酶联免疫试剂初筛，初筛阳性标本用蛋白印记法（WB）进行确证。结果8414名羁押人员中，检出20例HIV阳性者，其中男性18人，女性2人，总检出率为0．24％。HIV感染者经吸毒感染8人（占总阳性数的40．00％），有注射吸毒史者阳性率5．26％；经性途径感染4人（占总阳性数的20．00％），有性乱史者阳性率1．12％；经血液感染1人，7人感染途径不详。结论扬州市监管场所中羁押人员HIV感染率较高，感染者主要为吸毒和性乱人员。