Biotechnology

Year: 2022 | Volume: 21 | Issue: 4 | Page No.: 163-170
DOI: 10.3923/biotech.2022.163.170

Bacterial Infections among Restaurant Workers Offered Meals in Some Restaurants in Mukalla City/Hadhramout, Yemen

Hassan Pyar and Wedad M. Al-Haik

Abstract: Background and Objective: Food handlers with poor personal hygiene who work in foodservice establishments could be potential infection sources. This study aims to identify the types of bacterial infection among workers who provide meals as a source of contamination in Mukalla restaurants, Hadhramout, Yemen. Materials and Methods: Bacteria were isolated on a general and selective medium and then their phenotypic characteristics and biochemical assays were examined, as well as a disk agar diffusion test. Results: The results showed that the contamination rate of the samples taken from workers who provide meals was 36 samples from the total 48 samples and the most contaminated samples were isolated from hands followed by noses and clothes. The high contaminated samples were workers with primary education followed by secondary education and illiterate with 52.7, 30.6 and 16.7%, respectively. The isolates were gram-positive and gram-negative bacteria with 55.6 and 44.4%, respectively. Escherichia coli showed the highest percentage (47.2%) among the isolated bacteria. Antibiotic sensitivity test showed that imipenem was a higher resistance with all isolates while tetracycline was sensitive against E. coli and Micrococcus sp. Conclusion: Significant bacterial infection was detected among restaurant workers as a source of contamination. These findings underscore the crucial importance of preventative measures and extensive primary health care and hygiene training.

Keywords: Escherichia coli, food handlers, sanitisers, sensitivity test, pathogenic organisms, Consumers and mortality

INTRODUCTION

Diarrheal illnesses, which are primarily caused by foodborne microbial infections, are a primary cause of illness and mortality in underdeveloped nations, They kill an estimated 1.9 million people each year. Even in wealthy countries, microbiological foodborne infections afflict an estimated one-third of the population each year¹. As a result, a proper screening technique is beneficial in diagnosing food handlers, minimizing potential morbidity and safeguarding consumer health².

Hand washing using soap has long been recognized as a critical barrier to disease transmission in food preparation and delivery, as well as in health care settings such as restaurants and hotels. Many of these situations present several potentials for disease dissemination among at-risk groups, necessitating increased vigilance³. On the other hand, instant sanitisers or sanitary wipes are thought to be effective in preventing contamination and the spread of organisms among coworkers where water is limited or frequent hand hygiene is required daily, such as for many patients in hospitals and restaurants^4-6. As a result, hand hygiene is critical for preventing disease and wearing gloves can lessen the risk of food contamination⁷. These procedures are not casefully carried out adequately since they take 15-20 seconds to be effective. A short rinse with water followed by shaking to dry hands can loosen any contained microbes on the skin, allowing for easier transfer during hand contact with people or things like food contact surfaces^5,8. Outbreaks caused by workers infected with norovirus, Hepatitis A Virus (HAV), Salmonella sp. and Shigella sp., has been made previously⁹.

Food is not only nutritious, but it is also frequently used as a culture medium for microorganisms to flourish. Because germs colonize the environment, foods are frequently contaminated with bacteria and other microbes. Food handlers play an important role in the interaction between the kitchen and the food being prepared or served^10,11.

Intestinal enteropathogenic bacteria are transmitted either directly or indirectly through faeces-contaminated materials including food, drink, nails and fingers they demonstrate the relevance of faecal-oral human-to-human transmission. Food handlers who possess and emit enteropathogenic bacteria may contaminate foods by touching them with their fingers, then contaminating food processing and lastly contaminating healthy people¹². In comparison to other regions, the area beneath the fingernails can be a vector for hazardous germs to spread through contamination¹³. Infected food workers have been demonstrated to be the source of several viral and bacterial infection outbreaks¹⁴. Food handlers at food service establishments with poor personal hygiene could be possible sources of infection from harmful organisms. As a result, it is essential to have regular check-ups for staff workers in the restaurants¹⁵. Therefore, a proper screening technique is helpful to diagnose food handlers, preventing likely morbidity and protecting the health of the customers².

Meals can be a significant source of harmful diseases to human health, such as diseases resulting from food contamination and eating foods containing certain numbers of live bacteria, such as intestinal infections, bacterial dysentery, cholera, typhoid fever and others or diseases resulting from food poisoning and mean diseases resulting from eating foods containing toxins produced by bacteria growing in food or the bacteria in the environment, such as intestinal infections, bacterial dysentery¹⁶.

Microorganisms including bacteria, viruses and parasites cause around 250 billion foodborne diseases, with approximately 105 billion instances of diarrhoea occurring annually in children under 5 years, resulting in approximately 3 million fatalities. According to the World Health Organization around 190 million instances of diarrhoea caused by contaminated food occur annually in the Eastern Mediterranean Region, with approximately 350 thousand cases resulting in death¹⁷.

In Yemen, many previous studies were conducted, where the intestinal parasites that dominate restaurant workers as food handlers were verified. The study included the northern governorates¹⁸, Hadhramout and Taiz Governorate^19,20.

Because there have been few studies in Hadhramout, Yemen, the goal of this study was to identify the types of bacterial infection among restaurant workers who deliver meals, as well as to evaluate the sensitivity of the isolated microorganisms.

MATERIALS AND METHODS

Sample collection: Forty-eight samples were collected from workers responsible for preparing meals in restaurants in Mukalla City, Hadhramout, Yemen, from different parts such as hands, clothes and noses from January to March, 2020 using a sterile cotton swab.

The swab was immersed in physiological saline solution (0.85% normal saline). Then the samples were transferred for cultivation in Dar Al Shifa Laboratory in Mukalla.

Cultivation of the sample: The samples were cultured on plates of nutrient agar by streaking method and incubated at 37°C for 24 hrs.

Isolation, purification and identification of bacteria: After the initial isolation of bacteria, there were grown again on selective media such as MacConkey agar and blood agar to ensure their purity by planning method and the plates were incubated at 37°C for 24 hrs. After incubation, the phenotypic characteristics of bacterial colonies (shape, size and colour) were studied. On the other hand, the microscopic characteristics of the cells were evaluated after staining by the gram stain technique to identify the shape and arrangement of the cells. Biochemical tests such as citrate test, urease test, kligler iron agar (KIA), oxidase test, catalase test, sulfide-indole-motility test (SIM), coagulase test, bacitracin test, novobiocin and DNase were conducted¹⁶. The isolated colonies were selected from each culture medium and inoculated on slanted agar (nutrient agar slant) and the tubes were incubated at 37°C for 24 hrs, then kept in the refrigerator at 4°C²¹.

Antibiotic susceptibility test: Antibiotic susceptibility tests were carried out by the Kirby-Bauer disk diffusion technique according to Clinical Laboratory Standard Institute guidelines. Mueller Hinton agar was used and lawn technique was performed^22,23. Five antibiotics disks (Oxoid, UK) were used against investigated bacteria. These antibiotics disks were sulfamethoxazole/trimethoprim (ST 10 μg), ceftriaxone (CRO 30 μg), imipenem (IPM 10 μg), amoxycillin (AMC 30 μg) and tetracycline (TC 30 μg).

RESULTS AND DISCUSSION

Estimation of bacterial contamination in samples: The result showed that from 48 samples collected from workers who provided meals, thirty-six samples (75%) were contaminated with microorganisms. The results indicated that the most contaminated samples were samples taken from the hands of workers followed by samples of noses and the workers’ clothes with percentages of 84, 66.7 and 64.7%, respectively (Table 1). This result indicated a low level of good personal hygiene among workers. A similar study was conducted in which a large percentage of intestinal parasites that predominated in restaurant workers as food handlers in Mukalla City, Hadhramout were isolated¹⁹. Similarity, a study was conducted in Thamar City, Yemen to explore the extent of bacterial contamination of the meals provided and the role of workers as a source of contamination. It found that the most contaminated with bacteria were workers’ hands followed by noses^24,25. Another study in Iran, 2006 was conducted to determine the effectiveness of simple hand washing in reducing bacterial hand contamination of workers presented of food in some restaurants²⁶.

Table 2 showed that most of the samples taken from the workers were in February (18 samples), so the most percentage of bacteria were isolated about 83.3% (15 bacterial isolates) in this month. In January and March 15 samples were taken in both months. Therefore the contamination with bacteria was 80% (12 bacterial isolates) in March, but in January it was 60% (9 bacterial isolates).

Information for restaurant workers: It was monitored from the screening of the educational level of restaurant workers that the most contaminated samples were workers with primary education workers, followed by secondary education level workers and the least from illiterate workers with the percentage of 52.7, 30.6 and 16.7%, respectively. It is clear from Table 3 that education plays a very important role in developing the workers’ responsiveness of following the methods of occupational safety and staying away from pollutants. This result is lined with Baswaid and Al-Haddad¹⁹. They reported that the most contaminated samples with intestinal parasites were from workers handling meals in Mukalla restaurants who had a primary education level followed by those with a secondary education level and the least contaminated samples were from illiterate workers with the percentage rate of 63.5, 25.2 and 11.3%, respectively.

Table 4 indicates age groups with contaminated samples were, 20 samples in the age of 18-20 years followed by 12 samples in the age of 20-30, while the least age group was 31-39 years old with 4 contaminated samples.

Identification and characterization of isolated bacteria: The isolated bacteria were examined microscopically, (a) Gram-positive cocci bacteria were blue with a circular form and (b) Gram-negative Bacilli bacteria were pink in colour with an oval shape Fig. 1a and b. The biochemical tests of isolated bacteria were presented in Table 5 and 6. Thirty-six contaminated samples were isolated from a total of 48 samples from workers responsible for preparing meals in restaurants in Mukalla City, Hadhramout, Yemen. Sixteen isolates were gram-negative bacteria whereas, twenty isolates were gram-positive bacteria with 44.4 and 55.6%, respectively. Gram-positive bacteria identified as Staphylococcus aureus, Staphylococcus epidermidis and Micrococcus sp. On the other hand, gram-negative isolated bacteria were identified as E. coli, Pseudomonas sp. and Proteus sp.

These results were in the agreement with other researchers who found that the most isolated bacteria from restaurant workers in Thamar City, Yemen were Staphylococcus aureus, E. coli and Pseudomonas aureginosa²⁷. Hands of workers showed the highest percentage of isolated bacteria with 21 samples from a total of 36 samples followed by worker’s clothes (11 out of 36 isolates) and workers’ noses (4 out of 36 isolates) with 58.3%, 30.6% and 11.1%, respectively. The most percentage of isolated bacteria were E. coli from hands (10 out of 36 isolates) and clothes (7 out of 36 isolates) of workers’ with 27.8 and19.4%, respectively. Staphylococcus aureus was the most isolated (5.6%) from the workers’ nose (2 out of 36 isolates) with 5.6%. The same result with others who reached that the highest percentage of bacteria isolated from noses was Staphylococcus aureus, Pseudomonas aeruginosa and E. coli from workers’ noses^25,28,29.

Table 7 and Fig. 2 showed that the highest percentage of bacteria isolated from the hands of workers were E. coli followed by S. epidermidis with 47.2 and 22.2%, respectively. These results indicated that the contamination was from human and animal waste (faeces) due to their natural presence in the intestines, which may be due to the possibility of not using detergents such as soap or any sterilizers to clean their hands, especially after using the health facilities^27,30. These guidelines emphasize the significance of food service personnel washing their hands and preventing sick workers from coming into close contact with food³¹.

The result showed that S. aureus was present in the workers’ hands and noses with 13.8%. It may depend on evidence of contamination from wounds that may be found on the outer surface of the skin in most of these workers. Moreover it was noticed that the workers do not wear gloves during working^32,33. Beyene et al.³⁴ reported that S. aureus colonized 28.7% of the 300 food handlers in Jimma Town Southwest Ethiopia who worked in hotels and restaurants. The frequency of S. aureus isolation from the nose, hand and both. The researchers confirmed the isolation of enterotoxin-producing S. aureus from the noses of healthy carriers, they can anticipate the real danger posed by those carriers of this bacteria preparing meals, especially since they do not wear masks, thus are a source of polluting the air, environment (clothes) and food with these bacteria^28,34-36. The result showed that Pseudomonas sp., was not present in the hands and noses of the workers and only present in 2.8% of workers’ clothes. Many pathogenic bacteria that caused food poisoning were found at restaurants and several key institutions, including S. aureus, Pseudomonas sp., Salmonella sp., Shigella sp., E. coli, Bacillus sp. and Clostridium perfringeus³⁷. The prevalence of food-borne diseases has risen in recent years, attracting the attention of numerous academics³⁸. Foodborne diseases occurred due to foods prepared in restaurants and other institutions and 20% of these diseases were caused by foods prepared the homes.

Food handlers were considered one of the most important sources of food contamination with pathogenic microorganisms, especially infected persons or healthy carriers, who were considered an important source of infection for their ability to transmit germs from patients themselves³⁹. Otherwise contamination can occur when making food using infected devices and instruments or from a contaminated kitchen environment as a result of a lack of health conditions and rules⁴⁰.

Antibiotic susceptibility test: The results of the bacterial isolate (36 isolates) from worker’s in Mukalla restaurants, Yemen, showed variable resistante patterns as shown in Table 8. Imipenem was the antibiotic that showed the highest resistance to all isolates (S. aureus, S. epidermidis, Pseudomonas sp. and Proteus sp.) 100%. Tetracycline was a more sensitive antibiotic to E. coli and Micrococcus sp. This result was in line with a study result reported by Tesfaye et al.⁴¹. It was also comparable with the results of of Emeakaroha et al.⁴².

There were no isolates that were sensitive to all drugs. The presence of microbial contaminations on restaurant workers was generally unwanted since they might spread bacterial diseases throughout the food. As a result, hands and clothes may serve as reservoirs for food contamination. There is a need to educate employees, managers, customers and anybody else who works in a restaurant on the hygienic and right handling of these materials.

CONCLUSION

The present study observed the isolation and identification of significant bacteria as a source of contamination among restaurant workers. A sensitivity test for isolated bacterial was performed. These findings highlight the critical need for protective measures such as improved public awareness campaigns, regular food handler monitoring for food borne microorganisms, intensive primary health care and hygiene training. The usage of face masks by restaurant workers as well as regular medical examinations may help to limit the spread of microorganisms.

SIGNIFICANCE STATEMENT

This study discovers the prevalence of pathogenic bacteria among food handlers in Mukalla City Hadhramout Governorate, Yemen. Escherichia coli which is predominant, was isolated from food handlers. Because of this study findings, tetracycline was recommend as a drug of choice in the treatment of infections based on its demonstrated high sensitivity. This study helps the researchers in conducting additional research at different restaurants in different cities of Hadhramout governorate, Yemen to highlight the importance of preventative methods and broad primary health care and hygiene training.

ACKNOWLEDGMENTS

The authors would like to thank Hadhramout University, Yemen for providing the chemicals and culture media used in this study, also the authors would like to thank the research team of the Department of Biology, Faculty of Science, Hadhramout University, Yemen.

REFERENCES