ABSTRACT
Methicillin-Resistant Staphylococcus aureus (MRSA) is a ubiquitous public health challenge, with its prevalence in human, animal, and environmental interfaces posing significant concerns. This study aimed to characterize and detect the zoonotic linkages of MRSA within the cow-environment-human interfaces in dairy farms to address the One Health perspective. A comprehensive investigation, involving 636 samples (an equal number of raw milk and cow nasal swab samples, along with varying numbers of human nasal swab and environmental samples), revealed an overall MRSA prevalence of 13.4% (n = 271/636). Notably, environmental samples exhibited the highest prevalence (19.3%), emphasizing the potential role of farm surroundings in MRSA transmission, while the lowest prevalence was found in raw milk at 11.8% (n = 31/263). The prevalence in cow nasal swabs and human nasal swabs was 13.3% (n = 35/263) and 15.1% (n = 8/53), respectively. Multiplex PCR analysis revealed the presence of different Staphylococcal enterotoxin (SEa, SEb, SEc, and SEd), and exfoliative toxin-producing genes (Eta, Etb) within the MRSA isolates underlining their potential to induce public health threats. All MRSA isolates exhibited complete resistance to Oxacillin (100%) and Amoxicillin (100%), while the highest sensitivity was observed for Vancomycin (85.8%). Furthermore, these MRSA strains demonstrated varying degrees of resistance to other commonly used antimicrobial drugs, including Cefoxitin (75.3%), Ceftarolin (71.2%), Sulfamethoxazole-Trimethoprim (63.5%), Ciprofloxacin (60%), and Gentamicin (49.5%). Detection of MRSA in cow, human, and environmental samples within the same farm vicinity highlights the risk of zoonotic transmission of MRSA from cows to humans through environmental interfaces. Phylogenetic analysis of the mecA gene in MRSA isolates from all sources within the same farm revealed a high similarity index (>84%) among them suggesting a shared evolutionary origin. Moreover, the MRSA isolates from milk samples showed a close evolutionary relationship with isolates from Kenya and Brazil, while the isolates from humans and the environment displayed noticeable resemblance to isolates from several Asian countries. The findings emphasize the importance of collaborative efforts under the One Health framework to address this multifaceted issue and ensure the safety of our food supply and public health.
ABSTRACT
BACKGROUND: In the context of zoonosis, Bangladesh's small-scale dairying is yet to frame satisfactory levels due to poor biosecurity practices. OBJECTIVES: This study intended to reveal the degree of knowledge, attitudes and biosecurity practices among Sylhet district, Bangladesh's small-scale dairy farmers. We also focused on the association between biosecurity practices and the incidence of non-specific enteritis in humans. METHODS: A questionnaire-based survey was conducted on the farmers' KAP via personal interviews of 15 farmers from the randomly selected fifteen small-scale dairy farms. The questionnaire was developed with 6 questions for knowledge, 6 questions for attitude and 12 questions for the practice of biosecurity measures. Alongside that, data on the number of non-specific enteritis cases experienced by the farmers or their family members were also recorded. Spearman correlation was used to find out the correlation among KAP variables and between practice scores and non-specific enteritis incidences. RESULTS: We found an insignificant (p > 0.05) influence of demographic characteristics over knowledge, attitude and biosecurity practices. Significant (p < 0.05) and strong correlations were found in knowledge-attitude (r = 0.65), knowledge-practice (r = 0.71) and attitude-practice (r = 0.64). Incidences of non-specific enteritis and biosecurity measures' practice were also strongly correlated (r = -0.9232) and statistically significant (p < 0.05). CONCLUSIONS: Our study suggests that increasing knowledge and developing a good attitude are necessary to increase the adaptation of biosecurity measures as three of these factors are correlated. Moreover, farm biosecurity measures are closely related to human health.
