Prevalence and survival of Campylobacter in Egyptian dairy products

Current State of Salmonella, Campylobacter and Listeria in the Food Chain across the Arab Countries: A Descriptive Review

Foodborne infections caused by bacterial pathogens are a common cause of human illness in the Middle East, with a substantial burden of economic loss and public health consequences. This review aims at elucidating recent literature on the prevalence of Non-Typhoidal Salmonella (NTS), Campylobacter and Listeria monocytogens in the food chain in the Arab countries, and to consolidate available evidence on the public health burden and the status of antimicrobial resistance (AMR) among the concerned three pathogens. The reviewed evidence points to a scarcity of understanding of the magnitude of NTS in the food chain in the Arab countries. Additionally, not much work has been done at the molecular characterization level to address the source-attribution of NTS in the Arab World. Very few surveys have been done on Campylobacter in the food chain in the Gulf Cooperation Council (GCC) countries. There is a gap in quantitative (counts/numbers) surveillance efforts for Campylobacter in the chicken meat supply across all Arab countries, despite the availability of some qualitative (presence/absence) surveillance data. While there are several reports on L. monocytogenes in animal-sourced foods, notably in North African Arab countries, fewer are published on L. monocytogenes in plant-sourced foods. Information on the L. monocytogenes serotypes and strain diversity circulating in the Arab region is widely lacking. Antibiotic resistance in the three pathogens is not fully understood across the Arab region, despite some reports indicating varying trends at the human-food interface. The literature evidence presented in this review stresses that Salmonella, Campylobacter and L. monocytogenes continue to challenge food safety and public health in the Arab countries.

Prevalence, Characterization, and Control of Campylobacter jejuni Isolated from Raw Milk, Cheese, and Human Stool Samples in Beni-Suef Governorate, Egypt

Our study aimed to determine the prevalence of Campylobacter jejuni isolated from raw milk, cheese, and human stool samples in Beni-Suef Governorate, Egypt, and to characterize the antibiotic resistance profile and virulence genes of the isolates. An additional objective was to evaluate the effectiveness of cinnamon oil and Lactobacillus acidophilus La5 for controlling C. jejuni in cheese. A total of 200 samples of raw milk and dairy products, including 50 samples of raw milk and 150 samples of three different types of cheese were used. Fifty-three human stool samples were also collected. The samples were tested for the presence of C. jejuni using culture and molecular methods. Campylobacter spp. were isolated from 9.5% (19/200) of the raw milk and cheese samples. The highest prevalence was observed in milk samples (18%), followed by Kareish cheese (14%) and Talaga cheese (6%). In contrast, C. jejuni was not found in any of the Feta cheese samples. Of the human stool samples, 21 (39.6%) were positive for C. jejuni. Of the isolates, 60-90% were highly resistant to the antimicrobial agents tested, that is, nalidixic acid, ciprofloxacin, and tetracycline. Virulent cadF and cdtA genes were detected in all isolates. As milk and dairy products are important sources of contamination, reducing the level of C. jejuni in them will lower the risk to consumers. We showed that L. acidophilus La5 was able to control C. jejuni in Kareish cheese, but cinnamon oil was less effective.

Prevalence and Survival of Stenotrophomonas Species in Milk and Dairy Products in Egypt

Stenotrophomonas maltophilia is a nosocomial, multidrug-resistant pathogen that causes significant economic losses in milk production and deterioration of dairy product quality. This study investigates the prevalence and the survival of S. maltophilia under different food preservation conditions. A total of 240 samples, including farm-sourced milk, dairy shop purchased milk, Kareish cheese, Domiati cheese, ice cream, yoghurt, cooking butter, and unpasteurized cream were collected from various locations in Beni-Suef Governorate, Egypt. Thirty samples of each product were analyzed by standard biochemical tests for the presence of Stenotrophomonas spp., which was isolated from 36% (87/240) of the examined samples. The highest prevalence was observed in ice cream (80%), followed by unpasteurized cream (67%), whereas the lowest incidence was in Domiati cheese (3.3%). S. maltophilia, identified by PCR, was found only in unpasteurized cream (13%), cooking butter (10%), ice cream (6.7%), and dairy shop milk (3.3%). We also studied the viability of S. maltophilia in laboratory manufactured cream, butter, and cheese under different preservation conditions. S. maltophilia was able to survive for 30, 30, 28, 30, and 8 d in the inoculated cream, butter 0% salt, butter 3% salt, cheese 0% salt, and cheese 6% salt, respectively. Thus, S. maltophilia was able to survive more than predicted in all products in this study. This suggests that strains of S. maltophilia may develop adaptive strategies that enable survival under different food preservation conditions, which contradicts previous knowledge about the sensitivity of this microbe to environmental stress conditions. Our overall aim was to draw attention to the prevalence and future potential for increased public health significance of Stenotrophomonas spp.

Campylobacter at the Human-Food Interface: The African Perspective

The foodborne pathogen Campylobacter is a major cause of human gastroenteritis, accounting for an estimated annual 96 million cases worldwide. Assessment of the true burden of Campylobacter in the African context is handicapped by the under-reporting of diarrhoeal incidents and ineffective monitoring and surveillance programmes of foodborne illnesses, as well as the minimal attention given to Campylobacter as a causative agent of diarrhoea. The present review of the literature highlights the variability in the reported occurrence of Campylobacter in humans and animal food sources across different countries and regions in Africa. Campylobacter infection is particularly prevalent in the paediatric population and has been isolated from farm animals, particularly poultry, and foods of animal origin. The reported prevalence of Campylobacter in children under the age of five years ranges from 2% in Sudan to 21% in South Africa. In poultry, the prevalence ranges from 14.4% in Ghana to 96% in Algeria. This review also highlights the alarming trend of increased Campylobacter resistance to clinically important antimicrobials, such as ciprofloxacin and erythromycin, in humans and food animals in Africa. This review adds to our understanding of the global epidemiology of Campylobacter at the human–food animal interface, with an emphasis from the African perspective. Interinstitutional and intersectoral collaborations, as well as the adoption of the One Health approach, would be useful in bridging the gaps in the epidemiological knowledge of Campylobacter in Africa.

A Comprehensive Review of Common Bacterial, Parasitic and Viral Zoonoses at the Human-Animal Interface in Egypt

Egypt has a unique geographical location connecting the three old-world continents Africa, Asia and Europe. It is the country with the highest population density in the Middle East, Northern Africa and the Mediterranean basin. This review summarizes the prevalence, reservoirs, sources of human infection and control regimes of common bacterial, parasitic and viral zoonoses in animals and humans in Egypt. There is a gap of knowledge conerning the epidemiology of zoonotic diseases at the human-animal interface in different localities in Egypt. Some zoonotic agents are “exotic” for Egypt (e.g., MERS-CoV and Crimean-Congo hemorrhagic fever virus), others are endemic (e.g., Brucellosis, Schistosomiasis and Avian influenza). Transboundary transmission of emerging pathogens from and to Egypt occurred via different routes, mainly importation/exportation of apparently healthy animals or migratory birds. Control of the infectious agents and multidrug resistant bacteria in the veterinary sector is on the frontline for infection control in humans. The implementation of control programs significantly decreased the prevalence of some zoonoses, such as schistosomiasis and fascioliasis, in some localities within the country. Sustainable awareness, education and training targeting groups at high risk (veterinarians, farmers, abattoir workers, nurses, etc.) are important to lessen the burden of zoonotic diseases among Egyptians. There is an urgent need for collaborative surveillance and intervention plans for the control of these diseases in Egypt.

A systematic review and meta-analysis on the incubation period of Campylobacteriosis

Accurate knowledge of pathogen incubation period is essential to inform public health policies and implement interventions that contribute to the reduction of burden of disease. The incubation period distribution of campylobacteriosis is currently unknown with several sources reporting different times. Variation in the distribution could be expected due to host, transmission vehicle, and organism characteristics, however, the extent of this variation and influencing factors are unclear. The authors have undertaken a systematic review of published literature of outbreak studies with well-defined point source exposures and human experimental studies to estimate the distribution of incubation period and also identify and explain the variation in the distribution between studies. We tested for heterogeneity using I 2 and Kolmogorov-Smirnov tests, regressed incubation period against possible explanatory factors, and used hierarchical clustering analysis to define subgroups of studies without evidence of heterogeneity. The mean incubation period of subgroups ranged from 2·5 to 4·3 days. We observed variation in the distribution of incubation period between studies that was not due to chance. A significant association between the mean incubation period and age distribution was observed with outbreaks involving only children reporting an incubation of 1·29 days longer when compared with outbreaks involving other age groups.

Prevalence of Campylobacter jejuni and Campylobacter coli in raw milk and some dairy products

Aim:

This study was accomplished to test raw milk and certain dairy products sold in local markets of Qena, Egypt, for the presence of Campylobacter coli and Campylobacter jejuni.

Materials and Methods:

A total of 150 samples of raw milk, kareish cheese, and yoghurt (50 samples each) were subjected first to enrichment in Bolton broth at 42°C for 2 days under a microaerobic condition, subsequently campylobacter blood free selective agar plates were cultured and incubated in the same condition of the broth. Based on the morphological and biochemical themes of the growing colonies, it was further classified into Campylobacter spp. The identified isolates were later affirmed by polymerase chain reaction using primers that were designed to locate hipO genes in C. jejuni and glyA in C. coli.

Results:

Of the total 150 examined samples of raw milk and soft cheese samples; 37 (24.6%) samples were contaminated with Campylobacter spp. C. jejuni was dominating in this study in 20%, 14%, and 8% of the examined raw milk, kareish cheese, and yoghurt samples, respectively. No sample harbored C. coli.

Conclusion:

Campylobacter spp. could be detected in 24.6% of the investigated samples. C. jejuni isolated from 14% of the total tested samples, while C. coli could not be detected from the examined samples. Campylobacter spp. is rampant in the areas of poor hygienic conditions making products made from raw milk of public health hazard.

Prevalence and Antimicrobial Resistance of Campylobacter Isolated from Dressed Beef Carcasses and Raw Milk in Tanzania

Campylobacter species are commonly transmitted to humans through consumption of contaminated foods such as milk and meat. The aim of this study was to investigate the prevalence, antimicrobial resistance, and genetic determinants of resistance of Campylobacter isolated from raw milk and beef carcasses in Tanzania. The antimicrobial resistance genes tested included blaOXA-61 (ampicillin), aph-3-1 (aminoglycoside), tet(O) (tetracycline), and cmeB (multi-drug efflux pump). The prevalence of Campylobacter was 9.5% in beef carcasses and 13.4% in raw milk, respectively. Using multiplex-polymerase chain reaction (PCR), we identified 58.1% of the isolates as Campylobacter jejuni, 30.7% as Campylobacter coli, and 9.7% as other Campylobacter spp. One isolate (1.6%) was positive for both C. jejuni and C. coli specific PCR. Antimicrobial susceptibility testing using the disk diffusion assay and the broth microdilution method showed resistance to: ampicillin (63% and 94.1%), ciprofloxacin (9.3% and 11.8%), erythromycin (53.7% and 70.6%), gentamicin (0% and 15.7%), streptomycin (35.2% and 84.3%), and tetracycline (18.5% and 17.7%), respectively. Resistance to azithromycin (42.6%), nalidixic acid (64.8%), and chloramphenicol (13%) was determined using the disk diffusion assay only, while resistance to tylosin (90.2%) was quantified using the broth microdilution method. The blaOXA-61 (52.6% and 28.1%), cmeB (26.3% and 31.3%), tet(O) (26.3% and 31.3%), and aph-3-1 (5.3% and 3.0%) were detected in C. coli and C. jejuni. These findings highlight the extent of antimicrobial resistance in Campylobacter occurring in important foods in Tanzania. The potential risks to consumers emphasize the need for adequate control approaches, including the prudent use of antimicrobials to minimize the spread of antimicrobial-resistant Campylobacter.

Molecular identification of yeasts associated with traditional Egyptian dairy products

This study aimed to examine the diversity and ecology of yeasts associated with traditional Egyptian dairy products employing molecular techniques in yeast identification. A total of 120 samples of fresh and stored Domiati cheese, kariesh cheese, and "Matared" cream were collected from local markets and examined. Forty yeast isolates were cultured from these samples and identified using the restriction-fragment length polymorphism (RFLPs) of 5.8S-ITS rDNA region and sequencing of the domains D1 and D2 of the 26S rRNA gene. Yeasts were identified as Issatchenkia orientalis (13 isolates), Candida albicans (4 isolates), Clavispora lusitaniae (Candida lusitaniae) (9 isolates), Kodamaea ohmeri (Pichia ohmeri) (1 isolate), Kluyveromyces marxianus (6 isolates), and Candida catenulata (7 isolates). With the exception of C. lusitaniae, the D1/D2 26S rRNA gene sequences were 100% identical for the yeast isolates within the same species. Phylogenetic reconstruction of C. lusitaniae isolates grouped them into 3 distinguished clusters. Kariesh cheese was found to be the most diverse in its yeast floras and contained the highest total yeast count compared with other examined dairy products. This was linked to the acidic pH and lower salt content of this cheese, which favor the growth and survival of yeasts in foodstuffs. Stored Domiati cheese also contained diverse yeast species involving isolates of the pathogenic yeast C. albicans. This raises the possibility of dairy products being vehicles of transmission of pathogenic yeasts.