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Evaluation of multidrug-resistant Bacillus strains causing public health risks in powdered infant milk formulas
Mohamed N Alanber1, Naiyf S Alharbi1, Jamal M Khaled1
1Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia.
Background:
Antibiotic-resistant bacteria are one of the major global health issues that can affect humans, animals, and the environment. Antibiotic-resistant bacteria have emerged as opportunistic pathogenic bacteria that are frequently isolated from both clinical patients and healthy individuals. The aim of this study was to characterize the antibiotic-resistant bacteria isolated from powdered infant formulas marketed in Riyadh, Saudi Arabia.
Methods:
Infant powdered milk formulas were purchased from different pharmacies located within Riyadh, and ten products of powdered milk formulas designed for children of various ages were then transferred to the laboratory in the Department of Botany and Microbiology at King Saud University, Riyadh. Isolation and purification of Bacillus species were both performed according to standard protocols. The identification test was performed using the automated Vitek 2 system (BioMerieux, France), and antibiotic sensitivity tests were performed using the disk-diffusion method incorporating standard antibiotic disks foramikacin (30μg/disk), gentamicin (10μg/disk), imipenem (10μg/disk), moxifloxacin (5μg/disk), cefoperazone (75μg/disk), cefpodoxime (10μg/disk), ceftazidime (30μg/disk), and cefepime (30μg/disk). Statistical analysis was performed using Ward's method to obtain antibiotic resistance of the isolates.
Results:
The results obtained from the milk samples indicated that all isolates were sensitive to amikacin, gentamicin, and moxifloxacin. A group of isolates obtained from milk was resistant to cefoperazone by 6.49%, cefpodoxime by 25.9%, ceftazidime by 14.28%, and cefepime by 19.48%.
Conclusions:
Based on these findings, we concluded that the powdered infant formula marketed in Riyadh City may act as a source of bacterial isolates that are resistant to several standard antibiotics.
Insights
Antibiotic-resistant bacteria were found in powdered infant formulas in Riyadh, Saudi Arabia. While sensitive to some antibiotics, certain strains showed resistance to others, posing a potential health risk.
Area of Science:
- Microbiology
- Public Health
- Food Safety
Background:
- Antibiotic-resistant bacteria (ARB) pose a significant global health threat, impacting humans, animals, and the environment.
- ARB are increasingly recognized as opportunistic pathogens, found in both clinical and healthy populations.
- The presence of ARB in food products, like infant formula, is a growing concern for public health.
Purpose of the Study:
- To investigate and characterize antibiotic-resistant bacteria isolated from powdered infant formulas available in Riyadh, Saudi Arabia.
- To assess the antibiotic susceptibility profiles of bacterial isolates from infant formula.
- To determine if infant formula could be a potential reservoir for antibiotic-resistant bacteria.
Main Methods:
- Powdered infant formulas were procured from pharmacies in Riyadh.
- Bacillus species were isolated and identified using standard microbiological techniques and the Vitek 2 system.
- Antibiotic susceptibility testing was performed using the disk-diffusion method against a panel of nine antibiotics, including amikacin, gentamicin, imipenem, moxifloxacin, cefoperazone, cefpodoxime, ceftazidime, and cefepime.
Main Results:
- All bacterial isolates from the infant formula samples were susceptible to amikacin, gentamicin, and moxifloxacin.
- A proportion of isolates exhibited resistance to cefoperazone (6.49%), cefpodoxime (25.9%), ceftazidime (14.28%), and cefepime (19.48%).
- The findings indicate varying levels of resistance to specific antibiotics among the isolated bacteria.
Conclusions:
- Powdered infant formula marketed in Riyadh may serve as a source for bacterial isolates resistant to multiple antibiotics.
- This highlights a potential public health risk associated with antibiotic resistance transmission through food products.
- Further research is warranted to understand the implications of ARB in infant formulas and implement control measures.
