Human Campylobacter Infections Research Articles

Farm specific risk factors for Campylobacter colonisation in Danish and Norwegian broilers

Campylobacteriosis has become the leading bacterial zoonosis in humans in the European Union and other developed countries. There are many sources of human Campylobacter infections, but broilers and broiler meat have been shown to be the most important. In order to implement effective interventions that reduce the probability of Campylobacter colonisation of broiler flocks, it is essential to fully understand the risk factors involved.We present a bi-national risk factor survey comprising Campylobacter data from more than 5200 Danish and Norwegian indoor, conventional broiler flocks and the responses to a standardised questionnaire, with more than 40 explanatory variables from 277 Danish and Norwegian farms. We explored several models by using different combinations of the Danish and Norwegian data, including models with single-country datasets. All models were analysed using a generalized linear model using backwards elimination and forward selection.The results show that Norwegian broiler flocks had a lower risk of being colonised than Danish flocks. Farm specific variables that increased the risk of flocks becoming colonised with Campylobacter in both countries were: broiler houses older than five years; longer downtime (no. of days between flocks), probably a consequence of longer downtimes being associated with less focus on maintaining a high biosecurity level; broiler houses without a separate ante-room or barrier; and the use of the drinker nipples with cups or bells compared with nipples without cups.Additional country specific risk factors were also identified. For Norway, the risk of colonisation increased with increasing numbers of houses on a farm and when the water used for the broilers originated from surface water or bore holes instead of mains. For Denmark, having boot dips or low stocking density increased the risk of a flock becoming Campylobacter positive.The different model approaches allowed us to explore the effect of having a large number of data available to identify the significant variables. To a large extent, the country specific models identified risk factors that were also found in the bi-national model. However, the bi-national model identified more risk factors than the country specific models. This indicated that combining the data sets from the two countries did not disrupt the results but was beneficial due to the greater strength achieved in the statistical analyses and the possibility of examining interactions terms with the variable Country.

ERIC-PCR Genotyping of Some Campylobacter jejuni Isolates of Chicken and Human Origin in Egypt.

The public health importance of the genus Campylobacter is attributed to several species causing diarrhea in consumers. Poultry and their meat are considered the most important sources of human campylobacteriosis. In this study, 287 samples from chicken (131 cloacal swabs, 39 chicken skin, 78 chicken meat, and 39 cecal parts) obtained from retail outlets as well as 246 stool swabs from gastroenteritis patients were examined. A representative number of the biochemically identified Campylobacter jejuni isolates were identified by real-time PCR, confirming the identification of the isolates as C. jejuni. Genotyping of the examined isolates (n = 31) by enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) revealed a high discriminatory index of ERIC-PCR (D = 0.948), dividing C. jejuni isolates of chicken and human origins into 18 profiles and four clusters. The 18 profiles obtained indicated the heterogeneity of C. jejuni. Dendrogram analysis showed that four clusters were generated; all human isolates fell into clusters I and III. These observations further support the existence of a genetic relationship between human and poultry isolates examined in the present study. In conclusion, the results obtained support the speculation that poultry and poultry meat have an important role as sources of infection in the acquisition of Campylobacter infection in humans.

Survey of Campylobacter spp. in owned and unowned dogs and cats in Northern Italy

Campylobacteriosis is among the most common bacterial causes of human gastroenteritis worldwide and pet ownership has been identified as a risk factor for Campylobacter infection in humans. Since canine and feline prevalence data are scarce in Italy, the present study was carried out to assess the prevalence, species distribution and risk factors for Campylobacter infection in dogs and cats under different husbandry conditions. Rectal swabs were collected from 171 dogs (household pets, n = 100; shelter-housed dogs, n = 50; dogs from breeding kennels, n = 21) and 102 cats (household pets, n = 52; shelter-housed cats, n = 21; free-roaming cats n = 29) in Northern Italy.Campylobacter was isolated from 17% (n = 29) of dogs and 14.7% (n = 15) of cats. C. jejuni was the most common isolate in both species (Campylobacter spp.-positive dogs, 55.2%; Campylobacter spp.-positive cats, 53.3%), followed by C. upsaliensis (Campylobacter spp.-positive dogs, 27.6%; Campylobacter spp.-positive cats, 40%). Other Campylobacter species were rarely detected, but included C. hyointestinalis subsp. hyointestinalis, C. lari and C. coli in dogs and C. coli and C. helveticus in cats. Among considered variables (sex, age, origin, diarrhoea, season of sampling), origin was identified as a risk factor for dogs, with shelter-housed dogs at higher risk than household dogs (odds ratio, 2.84; 95% CI 1.17, 6.92; P = 0.021).The results of this study, particularly the high prevalence of C. jejuni in Campylobacter-positive animals, demonstrated that household and stray dogs and cats in Northern Italy might pose a zoonotic risk for humans. Moreover, biosecurity measures should be improved in dog shelters.

Prevalence, Antimicrobial Resistance and Risk Factors for Thermophilic Campylobacter Infections in Symptomatic and Asymptomatic Humans in Tanzania.

The genus Campylobacter comprises members known to be a leading cause of foodborne gastrointestinal illness worldwide. A study was conducted to determine the epidemiology and antimicrobial resistance of Campylobacter in humans in Morogoro, Eastern Tanzania. Isolation of Campylobacter from stool specimens adopted the Cape Town protocol. Campylobacter isolates were preliminarily identified by conventional phenotypic tests and subsequently confirmed by matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometry and polymerase chain reaction. Antimicrobial resistance testing employed the disc diffusion method. A small proportion of the test isolates was also subjected to agar dilution method. Risk factors for human illness were determined in an unmatched case-control study. Thermophilic Campylobacter were isolated from 11.4% of the screened individuals (n = 1195). The agreement between PCR and MALDI-TOF was perfect (κ = 1.0). Symptomatics and young individuals were infected with higher numbers than asymptomatic and adults, respectively. The majority (84.6%) of the isolates were C. jejuni and the remaining were C. coli. Isolates had highest resistance (95.6%) for colistin sulphate and lowest for ciprofloxacin (22.1%). The rates of resistance for other antibiotics (azithromycin, erythromycin, tetracycline, cephalothin, gentamycin, nalidixic acid, ampicillin, amoxycillin, norfloxacin, chloramphenicol) ranged from 44.1% to 89%. Comparison between disc diffusion and agar dilution methods indicated a good correlation, and the tests were in agreement to each other (κ ≥ 0.75). Human illness was found to be associated with young age and consumption of chicken meat and pre-prepared salad. Our data indicate the presence of antibiotic-resistant thermophilic Campylobacter in humans in the study area. There is a need for routine investigation of the presence of the organisms in gastroenteritis aetiology, including determination of their antibiotic susceptibilities.

Novel gentamicin resistance genes in Campylobacter isolated from humans and retail meats in the USA.

To understand the molecular epidemiology of gentamicin-resistant Campylobacter and investigate aminoglycoside resistance mechanisms. One-hundred-and-fifty-one gentamicin-resistant Campylobacter isolates from humans (n = 38 Campylobacter jejuni; n = 41, Campylobacter coli) and retail chickens (n = 72 C. coli), were screened for the presence of gentamicin resistance genes by PCR and subtyped using PFGE. A subset of the isolates (n = 41) was analysed using WGS. Nine variants of gentamicin resistance genes were identified: aph(2″)-Ib, Ic, Ig, If, If1, If3, Ih, aac(6')-Ie/aph(2″)-Ia and aac(6')-Ie/aph(2″)-If2. The aph(2″)-Ib, Ic, If1, If3, Ih and aac(6')-Ie/aph(2″)-If2 variants were identified for the first time in Campylobacter. Human isolates showed more diverse aminoglycoside resistance genes than did retail chicken isolates, in which only aph(2″)-Ic and -Ig were identified. The aph(2″)-Ig gene was only gene shared by C. coli isolates from human (n = 27) and retail chicken (n = 69). These isolates displayed the same resistance profile and similar PFGE patterns, suggesting that contaminated retail chicken was probably the source of human C. coli infections. Human isolates were genetically diverse and generally more resistant than the retail chicken isolates. The most frequent co-resistance was to tetracycline (78/79, 98.7%), followed by ciprofloxacin/nalidixic acid (46/79, 58.2%), erythromycin and azithromycin (36/79, 45.6%), telithromycin (32/79, 40.5%) and clindamycin (18/79, 22.8%). All human and retail meat isolates were susceptible to florfenicol. This study demonstrated that several new aminoglycoside resistance genes underlie the recent emergence of gentamicin-resistant Campylobacter, and that, in addition to contaminated retail chicken, other sources have also contributed to gentamicin-resistant Campylobacter infections in humans.

EU Summary Report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2013

The antimicrobial resistance data on zoonotic and indicator bacteria in 2013, submitted by 28 EU MSs, were jointly analysed by EFSA and ECDC. Resistance in zoonotic Salmonella and Campylobacter species from humans, animals and food, and resistance in indicator Escherichia coli and enterococci, as well as data on meticillin-resistant Staphylococcus aureus, in animals and food were addressed. ‘Microbiological’ resistance was assessed using epidemiological cut-off (ECOFF) values in animal and food isolates and, where possible, in human isolates. For human isolates interpreted based on clinical breakpoints, the ‘clinically’ resistant and ‘intermediate’ resistant categories were combined into a ‘non-susceptible’ group, resulting in close correspondence with the ECOFF-defined ‘microbiological’ resistance for most antimicrobials. In Salmonella from humans, high proportions of isolates were resistant to ampicillin, sulfonamides and tetracyclines, while proportions of isolates resistant to third-generation cephalosporins and clinically non-susceptible to fluoroquinolones generally remained low. In Salmonella and Escherichia coli isolates from fowl, pigs, cattle and meat thereof, resistance to ampicillin, tetracyclines and sulfonamides was commonly detected, while resistance to third-generation cephalosporins was generally uncommon. High to very high resistance to (fluoro)quinolones was observed in Salmonella from turkeys, fowl and broiler meat. In Campylobacter from humans, a high to very high proportion of isolates were resistant to ciprofloxacin and tetracyclines, while resistance to erythromycin was low to moderate. The resistance to fluoroquinolones in some MSs was extremely high; in such settings, the effective treatment option for human enteric Campylobacter infection may be significantly reduced. High to extremely high resistance to ciprofloxacin, nalidixic acid and tetracyclines was observed in Campylobacter isolates from fowl, broiler meat, pigs and cattle, whereas much lower levels were observed for erythromycin and gentamicin. Increasing trends in ciprofloxacin resistance were observed in Campylobacter from broilers and/or pigs in several MSs. Multi-resistance and co-resistance to critically important antimicrobials in both human and animal isolates were uncommon. A minority of isolates from animals belonging to a few Salmonella serovars (notably Kentucky and Infantis) had a high level of resistance to ciprofloxacin.

Rapid identification and classification of Campylobacter spp. using laser optical scattering technology

Campylobacter jejuni and Campylobacter coli are the two important species responsible for most of the Campylobacter infections in humans. Reliable isolation and detection of Campylobacter spp. from food samples are challenging due to the interferences from complex food substances and the fastidious growth requirements of this organism. In this study, a novel biosensor-based detection called BARDOT (BActerial Rapid Detection using Optical scattering Technology) was developed for high-throughput screening of Campylobacter colonies grown on an agar plate without disrupting the intact colonies. Image pattern characterization and principal component analysis (PCA) of 6909 bacterial colonies showed that the light scatter patterns of C. jejuni and C. coli were strikingly different from those of Salmonella spp., Escherichia coli O157:H7, and Listeria monocytogenes. Examination of a mixed culture of these microorganisms revealed 85% (34/40) accuracy in differentiating Campylobacter from the other three major foodborne pathogens based on the similarity to the scatter patterns in an established library. The application of BARDOT in real food has been addressed through the analysis of Campylobacter spiked ground chicken and naturally contaminated fresh chicken pieces. Combined with real-time PCR verification, BARDOT was able to identify Campylobacter isolates from retail chicken. Moreover, applying passive filtration to food samples facilitated the isolation of pure Campylobacter colonies and therefore overcame the interference of the food matrix on BARDOT analysis.

Campylobacter spp. isolation from infected poultry livers with and without necrotic lesions

This study was developed in order to understand the possible intervention of Campylobacter spp. as etiological agent of necrotic lesions in poultry livers. This way, Campylobacter spp. was isolated from poultry livers with and without necrotic lesions. Additionally, virulence factors (cadF and cdtB) and antimicrobial resistance profile of the isolated strains were analyzed. From a total of 39 liver samples analyzed, 21 presented lesions and 18 were clean. Campylobacter spp. was isolated from 80.9% of liver samples with necrotic lesions (17/21) and from 38.9% of liver samples without lesions (7/18). These results indicate poultry liver as a potential source of human Campylobacter infection, since this bacteria may remain viable in the internal liver tissue in undercooked conditions. A high resistance to nalidixic acid (100%), norfloxacin (100%), ciprofloxacin (95.8%), ampicillin (91.6%) and tetracycline (75%) was observed among Campylobacter spp. isolates. Also, PCR detection of cdtB and cadF virulence and toxin genes, revealed 75% and 68.8% of positive samples, respectively. Strains isolated from livers with and without lesions presented similar results with respect to virulence factors and to antimicrobial resistance profiles, evidencing that these putative pathogenic determinants are widespread among the isolates from poultry livers. Phi coefficient calculated in order to measure the degree of association, revealed a highly significant association (Phi ¼ 0.472; p-value < 0.01) between the presence of livers with hepatic necrosis lesions and Campylobacter isolation. This result indicates the possibility of using these macroscopic lesions as visible and reliable indicator of Campylobacter spp. presence in poultry flock, and, thus, becoming an important tool to support the implementation of corrective measures at poultry farms level. This methodology could contribute for an accurate time-efficient monitoring and the development of effective prevention and intervention measures for Campylobacter spp. infection with reduced cost.

Occurrence of Thermotolerant Campylobacter in Raw Poultry Meat, Environmental and Pigeon Stools Collected in Open-Air Markets.

Campylobacteriosis was the most commonly reported zoonosis for confirmed human cases in European Union during 2011. Poultry meat was very often implicated in Campylobacter infections in humans. In Italy commerce of raw poultry meat is common in open-air markets: these areas can be considered at high risk of bacterial contamination due to the high presence birds like pigeons. The aim of this study was to collect data about the contamination by thermotolerant Campylobacter of raw poultry meat commercialised in open-air markets, of work-surfaces in contact with poultry meat and of pigeon stools sampled in the market areas in Turin, Northern Italy. Between September 2011 and December 2012, 86 raw poultry meat samples, 86 environmental swabs and 108 animal samples were collected in 38 open-air markets. Analysis were carried out according to ISO10272-1:2006 standard. C.coli was detected in 2.3% (2/86) of raw poultry meat samples, whereas no swab (0/86) resulted positive. Of pigeon stool 28% (30/107) was positive for C.jejuni (83.3% C.jejuni subsp. jejuni and 16.7% C.jejuni subsp. doylei). C.jejuni subsp. jejuni was isolated from 1 dead pigeon. Our results showed lower rates of contamination than those reported at retail in Europe. Although samples were collected in areas at high risk of contamination, raw poultry meat and work surfaces reported a low level of presence of thermotolerant Campylobacter. The high percentage of C.jejuni isolated from pigeon stools showed the importance of a continuous application of preventive measures by the food business operators and the surveillance activity by the Competent Authority.

A prospective follow-up study on transmission of Campylobacter from poultry to abattoir workers.

Contact with poultry or poultry meat is a well-known risk factor for campylobacteriosis, but prospective studies on transmission of Campylobacter from chickens to humans during slaughter are scarce. In this study, we monitored transmission of Campylobacter from slaughtered chicken to originally culture-negative abattoir workers during the peak season of colonized chicken and human Campylobacter infection. Stool samples were obtained from 28 abattoir workers together with data on health status once a month between June and September 2010, with a follow-up sample collected in February 2011. Campylobacter-positive individuals and chicken flocks were identified by culture, and isolates were further characterized using molecular techniques. Campylobacter was isolated from seven asymptomatic individuals. Four of them had been newly employed and had not reported any previous Campylobacter infection. Four human isolates had matching genetic fingerprints with isolates from recently slaughtered chickens. Our results further support the role of chicken as the source of human Campylobacter infection but suggest that asymptomatic Campylobacter infection may occur even in individuals with only limited earlier exposure to Campylobacter.

The importance of climatic factors and outliers in predicting regional monthly campylobacteriosis risk in Georgia, USA

Incidence of Campylobacter infection exhibits a strong seasonal component and regional variations in temperate climate zones. Forecasting the risk of infection regionally may provide clues to identify sources of transmission affected by temperature and precipitation. The objectives of this study were to (1) assess temporal patterns and differences in campylobacteriosis risk among nine climatic divisions of Georgia, USA, (2) compare univariate forecasting models that analyze campylobacteriosis risk over time with those that incorporate temperature and/or precipitation, and (3) investigate alternatives to supposedly random walk series and non-random occurrences that could be outliers. Temporal patterns of campylobacteriosis risk in Georgia were visually and statistically assessed. Univariate and multivariable forecasting models were used to predict the risk of campylobacteriosis and the coefficient of determination (R 2) was used for evaluating training (1999–2007) and holdout (2008) samples. Statistical control charting and rolling holdout periods were investigated to better understand the effect of outliers and improve forecasts. State and division level campylobacteriosis risk exhibited seasonal patterns with peaks occurring between June and August, and there were significant associations between campylobacteriosis risk, precipitation, and temperature. State and combined division forecasts were better than divisions alone, and models that included climate variables were comparable to univariate models. While rolling holdout techniques did not improve predictive ability, control charting identified high-risk time periods that require further investigation. These findings are important in (1) determining how climatic factors affect environmental sources and reservoirs of Campylobacter spp. and (2) identifying regional spikes in the risk of human Campylobacter infection and their underlying causes.

Vaccination of poultry against Campylobacter in the EU: what are the economic benefits?

AbstractCampylobacter is the most commonly reported gastrointestinal bacterial pathogen in the European Union (EU) since 2005. Reportedly, 212,064 humans have been confirmed ill in 2010 due to a Campylobacter infection in the EU. The major source of infection, among sporadic human cases is to be found in the food chain, from farm-to-fork, where poultry meat is considered to be one of the major vehicles of Campylobacter infections in humans, accounting for 50–80% of reported cases. One way to reduce this economic loss to society is perhaps the introduction of a new Campylobacter vaccine, which could be administered to one-day old chicks. This would effectively reduce the outbreak of illness among the general population, enhancing general well-being, and increase the efficiency of the employed labor force. In the present paper, we assess the potential economic benefits of a mandatory vaccination program at the EU27 level. In this study, benefits are mainly assumed to comprise lower risk of illness due to Ca...

Campylobacteriosis in Urban versus Rural Areas: A Case-Case Study Integrated with Molecular Typing to Validate Risk Factors and to Attribute Sources of Infection

Campylobacter infection is a leading cause of bacterial gastroenteritis worldwide, and most clinical cases appear as isolated, sporadic infections for which the source is rarely apparent. From July 2005 to December 2007 we conducted a prospective case-case study of sporadic, domestically-acquired Campylobacter enteritis in rural versus urban areas and a prevalence study of Campylobacter in animal and environmental sources in the Eastern Townships, Quebec. Isolates were typed using Multilocus Sequence Typing (MLST) to reinforce the case-case findings and to assign a source probability estimate for each human isolate. The risk of human campylobacteriosis was 1.89-fold higher in rural than urban areas. Unconditional multivariate logistic regression analysis identified two independent risk factors associated with human Campylobacter infections acquired in rural area: occupational exposure to animals (OR = 10.6, 95% CI: 1.2–91, p = 0.032), and household water coming from a private well (OR = 8.3, 95% CI: 3.4–20.4, p<0.0001). A total of 851 C. jejuni isolates (178 human, 257 chicken, 87 bovine, 266 water, 63 wild bird) were typed using MLST. Among human isolates, the incidence rates of clonal complexes (CC) CC-21, CC-45, and CC-61 were higher in rural than urban areas. MLST-based source attribution analysis indicated that 64.5% of human C. jejuni isolates were attributable to chicken, followed by cattle (25.8%), water (7.4%), and wild birds (2.3%). Chicken was the attributable source for the majority of cases, independent of residential area, sex and age. The increased incidence in rural compared to urban areas was associated with occupational exposure to animals, particularly cattle among those aged 15–34 years, and with consumption of private well water. Both bovine and water exposure appeared to contribute to the seasonal variation in campylobacteriosis. These results provide a basis for developing public education and preventive programs targeting the risk factors identified.

Preventing Campylobacter at the Source: Why Is It So Difficult?

Campylobacteriosis in humans, caused by Campylobacter jejuni and Campylobacter coli, is the most common recognized bacterial zoonosis in the European Union and the United States. The acute phase is characterized by gastrointestinal symptoms. The long-term sequelae (Guillain-Barré syndrome, reactive arthritis, and postinfectious irritable bowel syndrome) contribute considerably to the disease burden. Attribution studies identified poultry as the reservoir responsible for up to 80% of the human Campylobacter infections. In the European Union, an estimated 30% of the human infections are associated with consumption and preparation of poultry meat. Until now, interventions in the poultry meat production chain have not been effectively introduced except for targeted interventions in Iceland and New Zealand. Intervention measures (eg, biosecurity) have limited effect or are hampered by economic aspects or consumer acceptance. In the future, a multilevel approach should be followed, aiming at reducing the level of contamination of consumer products rather than complete absence of Campylobacter.

Elucidating the aetiology of human Campylobacter coli infections.

There has been little research on the determinants of Campylobacter coli infection, despite its contributing up to 10% of human Campylobacter infections. A case-control and two case-case study methods explored the aetiology of C. coli over a one year period across Scotland. The case-control multivariate model found an increased risk of C. coli infection in people older than 19 years (O.R. = 3.352), and during the summer months (O.R. = 2.596), while residing in an urban area decreased the risk (O.R. = 0.546). The first case-case study compared C. coli and C. jejuni cases and also showed a higher risk of C. coli during the summer (O.R. = 1.313) and in people older than 19 years (O.R. = 0.791). Living in an urban area was associated with a reduced risk of infection (O.R. = 0.769). Multi-locus sequence typing (MLST) indicated that sheep and chicken C. coli sequence types (STs) were most frequently found in humans whilst those from cattle and pigs were rarer. MLST diversity was high in isolates from pigs and chicken, intermediate in human isolates, and low in ruminant isolates. The second case-case study used MLST data to ascribe putative sources of infection to the cases. The putative source for 40% of cases was chicken, with 60% acquired from other sources (ruminants 54% and pigs 6%). The case-case analysis also showed that female gender was a risk factor (O.R. = 1.940), which may be explained by females being more likely to prepare poultry in the home. These findings indicate differences between the aetiology of C. coli and C. jejuni infections: this should be taken into account by public health professionals when developing strategies to reduce the burden of human campylobacteriosis.

The Effect of Growth Temperature on the Pathogenicity of Campylobacter

Control of Campylobacter in the food chain requires a better understanding of the behaviour of the bacteria in relevant environments. Campylobacter species are largely non-pathogenic in poultry, the body temperature of which is 42°C. However, the bacteria are highly pathogenic in humans whose body temperature is 37°C. The aim of this study was to examine if switching from commensal to pathogenic behaviour was related to temperature. We examined the growth, motility and invasion of T84 cells by three species of Campylobacter: C. jejuni 81116, C. jejuni M1, C. coli 1669, C. coli RM2228 and C. fetus fetus NC10842 grown at 37 and 42°C. Our results suggest that C. jejuni isolates grow similarly at both temperatures but some are more motile at 42°C and some are more invasive at 37°C, which may account for its rapid spread in poultry flocks and for infection in humans, respectively. C. coli, which are infrequent causes of Campylobacter infections in humans, is less able to grow and move at 37°C compared to 42°C but was significantly more invasive at the lower temperature. C. fetus fetus, which is infrequently found in poultry, is less able to grow and invade at 42°C.

Practicalities of Using Non-Local or Non-Recent Multilocus Sequence Typing Data for Source Attribution in Space and Time of Human Campylobacteriosis

In this study, 1208 Campylobacter jejuni and C. coli isolates from humans and 400 isolates from chicken, collected in two separate periods over 12 years in The Netherlands, were typed using multilocus sequence typing (MLST). Statistical evidence was found for a shift of ST frequencies in human isolates over time. The human MLST data were also compared to published data from other countries to determine geographical variation. Because only MLST typed data from chicken, taken from the same time point and spatial location, were available in addition to the human data, MLST datasets for other Campylobacter reservoirs from selected countries were used. The selection was based on the degree of similarity of the human isolates between countries. The main aim of this study was to better understand the consequences of using non-local or non-recent MLST data for attributing domestically acquired human Campylobacter infections to specific sources of origin when applying the asymmetric island model for source attribution. In addition, a power-analysis was done to find the minimum number of source isolates needed to perform source attribution using an asymmetric island model. This study showed that using source data from other countries can have a significant biasing effect on the attribution results so it is important to carefully select data if the available local data lack in quality and/or quantity. Methods aimed at reducing this bias were proposed.

Human and animal Campylobacteriosis in Tanzania: A review.

The thermotolerant species of Campylobacter have become very important in public health, particularly as agents of infectious diarrhoea in human beings. Though the mechanism by which they cause disease is yet to be fully explained, they have been recognized as the leading cause of bacterial enteritis in both developed and developing countries. The organisms colonize different animal species without causing any symptoms of disease; and humans acquire infections through contact with or consumption of contaminated meat especially raw/undercooked poultry meat. The growing trend of antibiotic resistant Campylobacter isolates continues to pose significant public health challenges. In this review we present the available information generated in Tanzania about Campylobacter infections in humans and animals. We conducted a structured literature search of PUBMED and ScienceDirect electronic databases and identified 15 articles. Studies on humans reported Campylobacter infections in both symptomatic and asymptomatic subjects; with higher prevalence in children under the age of five years. Studies on animals found colonization of both domestic and wild species. Among isolates, some demonstrated antimicrobial resistance. The available information for both human and animal Campylobacteriosis in the country is sparse. It however provides an insight of the bacteriological and epidemiological aspects of Campylobacter infections in the country and eventually creates more awareness on the need to develop control strategies. Since the organism is zoonotic its control strategies should adopt the "One Health" approach involving collaborative efforts from veterinary and human medicine.

食肉の生食とカンピロバクター食中毒

食肉の生食とカンピロバクター食中毒

Molecular Epidemiology and Public Health Relevance ofCampylobacterIsolated from Dairy Cattle and European Starlings in Ohio, USA

Dairy cattle serve as a potential source for Campylobacter infection in humans. Outbreaks associated with consumption of either Campylobacter contaminated raw milk or contaminated milk after treatment were previously recorded in the United States. Further, starlings have been implicated in the spread of bacterial pathogens among livestock. Here, we determined the prevalence, genotypic, and phenotypic properties of Campylobacter isolated from fecal samples of dairy cattle and starlings found on the same establishment in northeastern Ohio. Campylobacter were detected in 83 (36.6%) and 57 (50.4%) out of 227 dairy and 113 starling fecal samples, respectively. Specifically, 79 C. jejuni, five C. coli, and two other Campylobacter spp. were isolated from dairy feces, while all isolates from starlings (n=57) were C. jejuni. Our results showed that the prevalence of C. jejuni in birds was significantly (p<0.01) higher than that in dairy cattle. The pulsed-field gel electrophoresis analysis showed that C. jejuni were genotypically diverse and host restricted; however, there were several shared genotypes between dairy cattle and starling isolates. Likewise, many shared clonal complexes (CC) between dairy cattle and starlings were observed by multilocus sequence typing (MLST) analysis. As in humans, both in cattle and starlings, the CC 45 and CC 21 were the most frequently represented CCs. As previously reported, CC 177 and CC 682 were restricted to the bird isolates, while CC 42 was restricted to dairy cattle isolates. Further, two new sequence types (STs) were detected in C. jejuni from dairy cattle. Interestingly, cattle and starling C. jejuni showed high resistance to multiple antimicrobials, including ciprofloxacin, erythromycin, and gentamicin. In conclusion, our results highlight starlings as potential reservoirs for C. jejuni, and they may play an important role in the epidemiology of clinically important C. jejuni in dairy population.