Association between community socioeconomic factors, animal feeding operations, and campylobacteriosis incidence rates: Foodborne Diseases Active Surveillance Network (FoodNet), 2004-2010

Epidemiological and Genomic Characterization of a Campylobacter jejuni Outbreak in Lishui, China

Campylobacter is one of the leading causes of bacterial foodborne diarrheal diseases throughout the world. Reported outbreaks of Campylobacter are infrequent in China. This article described such an outbreak among students from a junior high school in East China during November 2019. A total of 40 samples were collected as follows: 24 stool samples from patients, 12 stool samples from kitchen staff members, and 4 water samples from cafeteria. The stool samples were tested for the presence of Salmonella, enterotoxigenic Escherichia coli, Shigella, Vibrio parahaemolyticus, Vibrio cholera, Listeria monocytogenes, Staphylococcus aureus, Yersinia enterocolitica, Bacillus cereus, Clostridium perfringens, norovirus, rotavirus, adenovirus, astrovirus, and sapovirus by real-time polymerase chain reaction (PCR). Pulsed-field gel electrophoresis (PFGE), next-generation sequencing, and antimicrobial susceptibility testing were performed to determine the relatedness of the Campylobacter jejuni isolates in this outbreak. Forty-seven cases were reported with diarrhea among 569 seventh grade students and staff. In these 47 cases, we detected that C. jejuni through real-time PCR in 16 fecal samples was positive, whereas the remaining fecal samples were tested negative by real-time PCR. Only three C. jejuni strains were isolated from stool samples of case patients, and all of them showed 100% PFGE similarity to strain ST6913. Whole genome sequencing analysis revealed no single nucleotide variation in the three isolates. This is one of the few reports in China about outbreak caused by C. jejuni. C. jejuni ST6913 was responsible for this outbreak.

A systematic review of animal feeding operations including concentrated animal feeding operations (CAFOs) for exposure, health outcomes, and environmental justice

BACKGROUND

Despite growing literature on animal feeding operations (AFOs) including concentrated animal feeding operations (CAFOs), research on disproportionate exposure and associated health burden is relatively limited and shows inconclusive findings.

OBJECTIVE

We systematically reviewed previous literature on AFOs/CAFOs, focusing on exposure assessment, associated health outcomes, and variables related to environmental justice (EJ) and potentially vulnerable populations.

METHODS

We conducted a systematic search of databases (MEDLINE/PubMed and Web of Science) and performed citation screening. Screening of titles, abstracts, and full-text articles and data extraction were performed independently by pairs of reviewers. We summarized information for each study (i.e., study location, study period, study population, study type, study design, statistical methods, and adjusted variables (if health association was examined), and main findings), AFO/CAFO characteristics and exposure assessment (i.e., animal type, data source, measure of exposure, and exposure assessment), health outcomes or symptoms (if health association was examined), and information related to EJ and potentially vulnerable populations (in relation to exposure and/or health associations, vulnerable populations considered, related variables, and main findings in relation to EJ and vulnerable populations).

RESULTS

After initial screening of 10,963 papers, we identified 76 eligible studies. This review found that a relatively small number of studies (20 studies) investigated EJ and vulnerability issues related to AFOs/CAFOs exposure and/or associated health outcomes (e.g., respiratory diseases/symptoms, infections). We found differences in findings across studies, populations, the metrics used for AFO/CAFO exposure assessment, and variables related to EJ and vulnerability. The most commonly used metric for AFO/CAFO exposure assessment was presence of or proximity to facilities or animals. The most investigated variables related to disparities were race/ethnicity and socioeconomic status.

CONCLUSION

Findings from this review provide suggestive evidence that disparities exist with some subpopulations having higher exposure and/or health response in relation to AFO/CAFO exposure, although results varied across studies.

Association between Precipitation Events, Drought, and Animal Operations with Campylobacter Infections in the Southwest United States, 2009-2021

BACKGROUND

Weather variability is associated with enteric infections in people through a complex interaction of human, animal, and environmental factors. Although Campylobacter infections have been previously associated with precipitation and temperature, the association between precipitation and drought on campylobacteriosis has not been studied.

OBJECTIVE

Using data from Arizona, Colorado, New Mexico, and counties in Utah, this ecological study aimed to assess the association between precipitation and the incidence of campylobacteriosis by county from 2009 to 2021 and to determine how this association is modified by prior drought level and animal operations.

METHODS

We merged 38,782 cases of campylobacteriosis reported in 127 counties with total precipitation (in inches), temperature (in average degrees Fahrenheit), Palmer Drought Severity Index (PDSI, category), and animal census data (presence, density per square mile) by week from 2009 to 2021. Negative binomial generalized estimating equations adjusted for temperature with a 3-wk lag were used to explore the association between precipitation on campylobacteriosis with resulting incidence rate ratios (IRRs). Stratified analyses explored the association with precipitation following antecedent drought, presence of farm operations, and animal density.

RESULTS

A 1-in (25.4  mm ) increase in precipitation was associated with a 3% increase in campylobacteriosis reported 3 wks later (IRR = 1.03; 95% CI: 1.02, 1.04) after adjusting for average temperature and PDSI. Compared with normal conditions, there were significantly more cases when precipitation followed antecedent extremely wet (IRR = 1.15; 95% CI: 1.04, 1.26), very wet (IRR = 1.09; 95% CI: 1.01, 1.18), moderately wet (IRR = 1.06; 95% CI: 1.01, 1.12), moderate drought (IRR = 1.11; 95% CI: 1.07, 1.16), and severe drought (IRR = 1.06; 95% CI: 1.02, 1.11) conditions, whereas there were significantly fewer cases (IRR = 0.89; 95% CI: 0.85, 0.94) for antecedent extreme drought. Compared to counties with no animal operations, counties with animal operations had significantly more cases following precipitation for every PDSI category except extreme drought. Counties with a higher density of beef cattle, goats for meat, chicken broilers, and chicken layers had significantly higher rates of campylobacteriosis following precipitation than those with no such operations, whereas those with dairy cattle and goats for milk, did not.

DISCUSSION

In this majority arid and semiarid environment, precipitation following prior wet conditions and moderate and severe drought were significantly associated with increased rates of campylobacteriosis, and only in prior extreme drought did rates decrease. Where the precipitation fell made a difference; after precipitation, counties with farm operations had significantly more cases compared to counties without farm operations. Further work should assess individual-level risk factors within environmental exposure pathways for Campylobacter. https://doi.org/10.1289/EHP14693.

A Cutoff Determination of Real-Time Loop-Mediated Isothermal Amplification (LAMP) for End-Point Detection of Campylobacter jejuni in Chicken Meat

Campylobacter jejuni is one of the leading causes of foodborne illness worldwide. C. jejuni is commonly found in poultry. It is the most frequent cause of contamination and thus resulting in not only public health concerns but also economic impacts. To test for this bacterial contamination in food processing plants, this study attempted to employ a simple and rapid detection assay called loop-mediated isothermal amplification (LAMP). The best cutoff value for the positive determination of C. jejuni calculated using real-time LAMP quantification cycle (Cq) was derived from the receiver operating characteristic (ROC) curve modeling. The model showed an area under curve (AUC) of 0.936 (95% Wald CI: 0.903–0.970). Based on Youden’s J statistic, the optimal cutoff value which had the highest sensitivity and specificity from the model was calculated as 18.07. The LAMP assay had 96.9% sensitivity, 95.8% specificity, and 93.9 and 97.9% positive and negative predictive values, respectively, compared to a standard culture approach for C. jejuni identification. Among all non-C. jejuni strains, the LAMP assay gave each of 12.5% false-positive results to C. coli and E. coli (1 out of 8 samples). The assay can detect C. jejuni at the lowest concentration of 103 CFU/mL. Our results suggest a preliminary indicator for the application of end-point LAMP assays, such as turbidity and UV fluorescence tests, to detect C. jejuni in field operations. The LAMP assay is an alternative screening test for C. jejuni contamination in food samples. The method provides a rapid detection, which requires only 9 min with a cutoff value of Cq. We performed the extraction of DNA from pure cultures and the detection of C. jejuni using the LAMP assay within 3 h. However, we were not able to reduce the time for the process of enrichment involved in our study. Therefore, we suggest that alternative enrichment media and rapid DNA extraction methods should be considered for further study. Compared to other traditional methods, our proposed assay requires less equipment and time, which is applicable at any processing steps in the food production chain.

A scoping review on data integration in the field of infectious diseases, 2009-2018

Background and Aim: Little is known about data integration in public health research and its impact. This study aimed to summarize known collaboration information, the characteristics of the datasets used, the methods of data integration, and knowledge gaps. Materials and Methods: We reviewed papers on infectious diseases from two or more datasets published during 2009- 2018, before the coronavirus disease pandemic. Two independent researchers searched the Medline and Global Health databases using predetermined criteria. Results: Of the 2375 items retrieved, 2272 titles and abstracts were reviewed. Of these, 164 were secondary reviews. Full-text reviews identified 153 relevant articles; we excluded 11 papers that did not meet our inclusion criteria. Of the 153 papers, 150 were single-country studies. Most papers were from North America (n=47). Viral diseases were the most commonly researched diseases (n=66), and many studies sought to define infection rates (n=62). Data integration usually employed unique national identifiers (n=37) or address-based identifiers (n=30). Two data sources were combined (n=121), and at least one data source typically included routine surveillance information. Conclusion: We found a growing usage of data integration in infectious diseases, emphasizing the advantages of data integration and linkage analysis, and reiterating its importance in public health emergency preparedness and response.

An analecta of visualizations for foodborne illness trends and seasonality

Disease surveillance systems worldwide face increasing pressure to maintain and distribute data in usable formats supplemented with effective visualizations to enable actionable policy and programming responses. Annual reports and interactive portals provide access to surveillance data and visualizations depicting temporal trends and seasonal patterns of diseases. Analyses and visuals are typically limited to reporting the annual time series and the month with the highest number of cases per year. Yet, detecting potential disease outbreaks and supporting public health interventions requires detailed spatiotemporal comparisons to characterize spatiotemporal patterns of illness across diseases and locations. The Centers for Disease Control and Prevention's (CDC) FoodNet Fast provides population-based foodborne-disease surveillance records and visualizations for select counties across the US. We offer suggestions on how current FoodNet Fast data organization and visual analytics can be improved to facilitate data interpretation, decision-making, and communication of features related to trend and seasonality. The resulting compilation, or analecta, of 436 visualizations of records and codes are openly available online.

Association between private drinking water wells and the incidence of Campylobacteriosis in Maryland: An ecological analysis using Foodborne Diseases Active Surveillance Network (FoodNet) data (2007-2016)

Campylobacter is a leading cause of bacterial foodborne illness in the United States. Campylobacter infections have most often been associated with food-related risk factors, such as the consumption of poultry and raw milk. Socioeconomic, agricultural and environmental factors, including drinking water source, can also influence the risk of campylobacteriosis. Approximately 19% of Maryland residents rely on private wells as their sole source of water. Given that the federal Safe Drinking Water Act does not regulate the water quality of private wells, these could be important non-foodborne transmission pathways for Campylobacter. To address this issue, data on the number of culture-confirmed cases of Campylobacter infection in Maryland between 2007 and 2016 were obtained from the Foodborne Diseases Active Surveillance Network. Cases were linked by zip code with data from the Maryland well permits registry, the 2010 U.S. Census, the 2016 American Community Survey, and the USDA Agricultural Census. Campylobacteriosis incidence rates and well prevalence were calculated by zip code. Negative binomial regression models were then constructed to evaluate the association between the prevalence of private wells, presence/absence of animal feeding operations and the incidence of campylobacteriosis across the physiographic provinces in Maryland. From 2007 to 2016, a total of 5746 cases of campylobacteriosis were reported in Maryland, and annual incidence rates ranged from 6.65 to 11.59 per 100,000 people. In our statewide analysis, a significant positive association was observed between well prevalence and increased campylobacteriosis incidence at the zip code level (Incidence Rate Ratio (IRR) = 1.35, 95% Confidence Interval (CI) = 1.11, 1.63). A significant positive association was also observed between well prevalence and increased campylobacteriosis incidence in the Appalachian and Coastal provinces of Maryland (IRR = 2.94, 95% CI = 1.11, 7.76 and IRR = 1.70, 95% CI = 1.25, 2.31, respectively). The presence of broiler chicken operations, increasing median age and percentage of residents living in poverty were also significantly associated with campylobacteriosis incidence at the zip code level in some physiographic provinces in Maryland. To our knowledge, these are the first US data to demonstrate an association between prevalence of private wells and campylobacteriosis incidence at the zip code level.

Occurrence and antimicrobial resistance of Campylobacter jejuni isolates from poultry in Casablanca-Settat, Morocco

Campylobacteriosis and Campylobacter spp. resistance to antibiotics represents a serious worldwide public health problem thermophilic Campylobacters, in particular, are major causes of gastroenteritis in humans. The aim of this study was to determine the prevalence and antimicrobial resistance of Campylobacter jejuni isolated from chicken droppings, of commercial poultry in the city of Casablanca, Morocco. Between February and September 2017, 140 samples of chicken droppings were collected and analyzed by classical bacteriology methods for isolation and identification according to Moroccan Standard NM ISO/TS 10272-3 (2013), followed by molecular identification (PCR: polymerase chain reaction). Among the 140 samples, 102 (73%) were positive by Campylobacter spp. tests and 38 (27.14 %) were negative to Campylobacter spp. Among the positive colonies, 41 (40, 2%) were C. jejuni. Of the 41 C. jejuni isolates, resistance was detected to tetracycline (100%), erythromycin (97%), ampicillin (85%), ciprofloxacin (77%), amoxicillin/ clavulanic acid (61.4%), and gentamicin (12.0%). In conclusion, the data obtained in the current study demonstrate that the majority of C. jejuni isolates evaluated were resistant to antimicrobials of the cycline, macrolide, and fluoroquinolone families, and all of the isolates were susceptible to gentamicin. Fluoroquinolone is the drug of choice for treating Campylobacter infections. These results underline the need for prudent use of antibiotics in poultry production to minimize the spread of antibioticresistant Campylobacter spp.

Relationship Between Census Tract–Level Poverty and Domestically Acquired Salmonella Incidence: Analysis of Foodborne Diseases Active Surveillance Network Data, 2010–2016

Background

The relationships between socioeconomic status and domestically acquired salmonellosis and leading Salmonella serotypes are poorly understood.

Methods

We analyzed surveillance data from laboratory-confirmed cases of salmonellosis from 2010–2016 for all 10 Foodborne Disease Active Surveillance Network (FoodNet) sites, having a catchment population of 47.9 million. Case residential data were geocoded, linked to census tract poverty level, and then categorized into 4 groups according to census tract poverty level. After excluding those reporting international travel before illness onset, age-specific and age-adjusted salmonellosis incidence rates were calculated for each census tract poverty level, overall and for each of the 10 leading serotypes.

Results

Of 52 821geocodable Salmonella infections (>96%), 48 111 (91.1%) were domestically acquired. Higher age-adjusted incidence occurred with higher census tract poverty level (P < .001; relative risk for highest [≥20%] vs lowest [<5%] census tract poverty level, 1.37). Children <5 years old had the highest relative risk (2.07). Although this relationship was consistent by race/ethnicity and by serotype, it was not present in 5 FoodNet sites or among those aged 18–49 years.

Conclusion

Children and older adults living in higher-poverty census tracts have had a higher incidence of domestically acquired salmonellosis. There is a need to understand socioeconomic status differences for risk factors for domestically acquired salmonellosis by age group and FoodNet site to help focus prevention efforts.

Insights into Livestock-Related Microbial Concentrations in Air at Residential Level in a Livestock Dense Area

Microbial air pollution from livestock farms has raised concerns regarding public health. Little is known about airborne livestock-related microbial levels in residential areas. We aimed to increase insights into this issue. Air measurements were performed in 2014 and 2015 at 61 residential sites in The Netherlands. Quantitative-PCR was used to assess DNA concentrations of selected bacteria (commensals: Escherichia coli and Staphylococcus spp.; a zoonotic pathogen: Campylobacter jejuni) and antimicrobial resistance (AMR) genes ( tetW, mecA) in airborne dust. Mixed models were used to explore spatial associations (temporal adjusted) with livestock-related characteristics of the surroundings. DNA from commensals and AMR genes was detectable even at sites furthest away from farms (1200 m), albeit at lower levels. Concentrations, distinctly different between sites, were strongly associated with the density of farms in the surroundings especially with poultry and pigs. C. jejuni DNA was less prevalent (42% of samples positive). Presence of C. jejuni was solely associated with poultry (OR: 4.7 (95% CI: 1.7-14), high versus low poultry density). Residential exposure to livestock-related bacteria and AMR genes was demonstrated. Identified associations suggest contribution of livestock farms to microbial air pollution in general and attribution differences between farm types. This supports the plausibility of recent studies showing health effects in relation to residential proximity to farms.

Campylobacteriosis, Salmonellosis, Yersiniosis, and Listeriosis as Zoonotic Foodborne Diseases: A Review

Zoonoses are diseases transmitted from animals to humans, posing a great threat to the health and life of people all over the world. According to WHO estimations, 600 million cases of diseases caused by contaminated food were noted in 2010, including almost 350 million caused by pathogenic bacteria. Campylobacter, Salmonella, as well as Yersinia enterocolitica and Listeria monocytogenes may dwell in livestock (poultry, cattle, and swine) but are also found in wild animals, pets, fish, and rodents. Animals, often being asymptomatic carriers of pathogens, excrete them with faeces, thus delivering them to the environment. Therefore, pathogens may invade new individuals, as well as reside on vegetables and fruits. Pathogenic bacteria also penetrate food production areas and may remain there in the form of a biofilm covering the surfaces of machines and equipment. A common occurrence of microbes in food products, as well as their improper or careless processing, leads to common poisonings. Symptoms of foodborne infections may be mild, sometimes flu-like, but they also may be accompanied by severe complications, some even fatal. The aim of the paper is to summarize and provide information on campylobacteriosis, salmonellosis, yersiniosis, and listeriosis and the aetiological factors of those diseases, along with the general characteristics of pathogens, virulence factors, and reservoirs.

Antimicrobial Resistance in Campylobacter Species: Mechanisms and Genomic Epidemiology

The Campylobacter genus is a large and diverse group of Gram-negative bacteria that are known to colonize humans and other mammals, birds, reptiles, and shellfish. While it is now recognized that several emerging Campylobacter species can be associated with human disease, two species, C. jejuni and C. coli, are responsible for the vast majority of bacterial gastroenteritis in humans worldwide. Infection with C. jejuni, in particular, has also been associated with a number of extragastrointestinal manifestations and autoimmune conditions, most notably Guillain-Barré syndrome. The antimicrobial drugs of choice for the treatment of severe Campylobacter infection include macrolides, such as erythromycin, clarithromycin, or azithromycin. Fluoroquinolones, such as ciprofloxacin, are also commonly used for empirical treatment of undiagnosed diarrheal disease. However, resistance to these and other classes of antimicrobial drugs is increasing and is a major public health problem. The US Centers for Disease Control and Prevention estimates that over 300,000 infections per year are caused by drug-resistant Campylobacter. In this chapter, we discuss the taxonomy of the Campylobacter genus, the clinical and global epidemiological aspects of Campylobacter infection, with an emphasis on C. jejuni and C. coli, and issues related to the treatment of infection and antimicrobial resistance mechanisms. We further discuss the use of next-generation sequencing for the detection and surveillance of antimicrobial resistance genes.

Residential proximity to high-density poultry operations associated with campylobacteriosis and infectious diarrhea

Poultry carry zoonotic bacteria that can cause gastroenteritis in humans. Environmental transmission of pathogens from poultry operations may increase gastrointestinal infection risk in surrounding communities. To evaluate associations between residential proximity to high-density poultry operations and individual-level diarrheal illnesses, we conducted a nested case-control study among 514,488 patients in Pennsylvania (2006-2015). Using electronic health records, we identified cases of five gastrointestinal outcomes: three pathogen-specific infections, including Escherichia coli (n = 1425), Campylobacter (n = 567), and Salmonella (n = 781); infectious diarrhea (n = 781); and non-specific diarrhea (2012-2015; n = 28,201). We estimated an inverse-distance squared activity metric for poultry operations based on farm and patient addresses. Patients in the second and fourth (versus first) quartiles of the poultry operation activity metric had increased odds of Campylobacter (AOR [CI], Q2: 1.36 [1.01, 1.82]; Q3: 1.38 [0.98, 1.96]; Q4: 1.75 [1.31, 2.33]). Patients in the second, third, and fourth quartiles had increased odds of infectious diarrhea (Q2: 1.76 [1.29, 2.39]; Q3: 1.76 [1.09, 2.85]; Q4: 1.60 [1.12, 2.30]). Stratification revealed stronger relations of fourth quartile and both Campylobacter and infectious diarrhea in townships, the most rural community type in the study geography. Increasing extreme rainfall in the week prior to diagnosis strengthened fourth quartile Campylobacter associations. The poultry operation activity metric was largely unassociated with E. coli, Salmonella, and non-specific diarrhea. Findings suggest high-density poultry operations may be associated with campylobacteriosis and infectious diarrhea in nearby communities, highlighting additional public health concerns of industrial agriculture.

Current and Potential Treatments for Reducing Campylobacter Colonization in Animal Hosts and Disease in Humans

Campylobacter jejuni is the leading cause of bacteria-derived gastroenteritis worldwide. In the developed world, Campylobacter is usually acquired by consuming under-cooked poultry, while in the developing world it is often obtained through drinking contaminated water. Once consumed, the bacteria adhere to the intestinal epithelium or mucus layer, causing toxin-mediated inhibition of fluid reabsorption from the intestine and invasion-induced inflammation and diarrhea. Traditionally, severe or prolonged cases of campylobacteriosis have been treated with antibiotics; however, overuse of these antibiotics has led to the emergence of antibiotic-resistant strains. As the incidence of antibiotic resistance, emergence of post-infectious diseases, and economic burden associated with Campylobacter increases, it is becoming urgent that novel treatments are developed to reduce Campylobacter numbers in commercial poultry and campylobacteriosis in humans. The purpose of this review is to provide the current status of present and proposed treatments to combat Campylobacter infection in humans and colonization in animal reservoirs. These treatments include anti-Campylobacter compounds, probiotics, bacteriophage, vaccines, and anti-Campylobacter bacteriocins, all of which may be successful at reducing the incidence of campylobacteriosis in humans and/or colonization loads in poultry. In addition to reviewing treatments, we will also address several proposed targets that may be used in future development of novel anti-Campylobacter treatments.