Molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) among veterinary students and personnel at a veterinary hospital in Malaysia

Antimicrobial resistance in methicillin-resistant staphylococcus aureus

In the medical community, antibiotics are revered as a miracle because they stop diseases brought on by pathogenic bacteria. Antibiotics have become the cornerstone of contemporary medical advancements ever since penicillin was discovered. Antibiotic resistance developed among germs quickly, placing a strain in the medical field. Methicillin-resistant Staphylococcus aureus (MRSA), Since 1961, has emerged as the major general antimicrobial resistant bacteria (AMR) worldwide. MRSA can easily transmit across the hospital system and has mostly gained resistance to medications called beta-lactamases. This enzyme destroys the cell wall of beta-lactam antibiotics resulting in resistance against that respective antibiotic. Daptomycin, linezolid and vancomycin were previously used to treat MRSA infections. However, due to mutations and Single nucleotide polymorphisms (SNPs) in Open reading frames (ORFs) and SCCmec machinery of respective antibody, MRSA developed resistance against those antibiotics. The MRSA strains (USA300, CC398, CC130 etc.), when their pan-genomes were analyzed were found the genes involved in invoking resistance against the antibiotics as well as the epidemiology of that respective strain. PENC (penicillin plus potassium clavulanate) is the new antibiotic showing potential in treatment of MRSA though it is itself resistant against penicillin alone. In this review, our main focus is on mechanism of development of AMR in MRSA, how different ORFs are involved in evoking resistance in MRSA and what is the core-genome of different antimicrobial resistant MRSA.

Characterisation and prevalence of community-associated MRSA among horses, dogs, cats and their human handlers: a cross-sectional study

Methicillin-resistant Staphylococcus aureus (MRSA) as an infectious organism of public health significance has evolved to a genetically distinct community-acquired MRSA with extended resistance to other than β-lactams. A cross-sectional study was conducted among 149 participants handling 446 animals (240 horses and 206 companion animals). The isolates were characterised as S. aureus and MRSA based on polymerase chain reaction detection of the nuc, mecA and mecC genes and the pvl gene for differentiation as community associated/livestock associated or hospital associated. The isolation rate of S. aureus from the human handlers' samples was 26 (17.4%) and 170 (38.1%) from the animal samples. The prevalence of MRSA among the isolates was 7 (4.7%) from the human handlers and 19 (4.3%) from the animals. Dogs and dog handlers had the highest isolation rates and were more likely to be colonized by S. aureus and MRSA compared with horses, cats and their handlers. The highest prevalence of MRSA was from horses (5.0%) and dog handlers (10.6%). This study has demonstrated a high prevalence of community associated MRSA in apparently healthy animals and their human handlers. This has important implications for antibiotic selection and use as well as infection control measures.

Prevalence and antimicrobial susceptibility pattern of methicillin-resistant Staphylococcus aureus isolates from retail raw meats in Turkey

The transmission of Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) through food products of animal origin may pose a public health concern. Therefore, the objectives of the present work were to determine the prevalence of S. aureus and MRSA in raw meat samples (beef, chicken, turkey, and duck) at retail level, and to determine the antimicrobial resistance profile of the MRSA isolates. Between September 2018 and January 2019, a total of 325 raw meat samples were collected from retail stores, and analysed for the presence of S. aureus and MRSA using primary enrichment method as well as using secondary selective enrichment methods for MRSA detection. All the suspected S. aureus and MRSA colonies obtained from the samples were confirmed by both phenotypic and genotypic methods. The MRSA isolates were tested against various antimicrobials, and the minimal inhibitory concentration (MIC) of vancomycin was determined. Macrolide-lincosamide-streptogramin B (MLSB) resistance phenotypes were also screened using the double-disk diffusion test. The overall prevalence of S. aureus was 57.2%, whereas the food-specific prevalence in beef, turkey, duck, and chicken samples was 75, 53, 48, and 46%, respectively. The overall prevalence of MRSA was 1.2%, whereas it was 3, 1, 0, and 0% in beef, turkey, chicken, and duck samples, respectively. All MRSA isolates were detected by the secondary selective enrichment method. These MRSA isolates had a variety of MLSB resistance phenotypes (i.e., iMLSB, cMLSB, and MS-MLSB) with vancomycin MIC values ranging between 1 - 2 µg/mL. These findings are important for developing interventions to reduce raw meat contamination with S. aureus and MRSA, and to improve public health.

Systematic review and meta-analysis of veterinary-related occupational exposures to hazards

Understanding hazards within the veterinary profession is critical for developing strategies to ensure the health and safety of personnel in the work environment. This study was conducted to systematically review and synthesize data on reported risks within veterinary workplaces. A systematic review of published data on occupational hazards and associated risk factors were searched within three database platforms namely PubMed, Ebscohost, and Google scholar. To determine the proportion estimates of hazards and pooled odds ratio, two random-effects meta-analysis were performed. For the biological, chemical and physical hazards, the pooled proportion estimates were 17% (95% CI: 15.0-19.0, p < 0.001), 7.0% (95% CI: 6.0-9.0%, p < 0.001) and 65.0% (95% CI: 39.0-91.0%, p < 0.001) respectively. A pooled odds ratio indicated the risk of exposures to physical (OR=1.012, 95% CI: 1.008-1.017, p < 0.001) and biological hazards (OR=2.07, 95% CI: 1.70-2.52, p <0.001) increased when working or in contact with animals. The review has provided a better understanding of occupational health and safety status of veterinarians and gaps within the developing countries. This evidence calls for policy formulation and implementation to reduce the risks of exposures to all forms of occupational-related hazards in veterinary workplaces.

Occurence and Antimicrobial Resistant Patterns of Methicillin Resistant Staphylococcus Aureus (MRSA) Among Practicing Veterinarians in Kebbi State, Nigeria

Methicillin-resistant Staphylococcus aureus (MRSA) is an emerging zoonotic pathogen incriminated in causing multiple disease conditions in humans and livestock. Studies have shown relationships between livestock rearing and increased MRSA colonization risk among farm workers, and also suggest that livestock may serves as reservoirs of the bacteria and could also infect humans via close contact and consumption of contaminated animal products. The aim of this study was to investigate if practicing veterinarians with significant livestock contacts are at risk for MRSA colonization. Therefore, a non-randomized survey was conducted to establish the presence of MRSA among veterinarians practicing in Kebbi State Nigeria, using both cultural characteristics and molecular detection of the resistant gene (mecA). Forty-one (41) nasal swabs were aseptically collected. The detection rate of MRSA in the veterinarians was 14.6 %. The study revealed a high occurrence rate of MRSA among veterinarians in the study area. The relatively high prevalence recorded among veterinarians in this study could be attributed to the poor understanding of MRSA as a disease, its mode of transmission and its status in the country which have contributed immensely to the little/no awareness of MRSA among veterinarians and hence making it favourable for the bacteria (MRSA) to spread.

Recommendations for approaches to meticillin-resistant staphylococcal infections of small animals: diagnosis, therapeutic considerations and preventative measures.: Clinical Consensus Guidelines of the World Association for Veterinary Dermatology

BACKGROUND

Multiple drug resistance (MDR) in staphylococci, including resistance to the semi-synthetic penicillinase-resistant penicillins such as meticillin, is a problem of global proportions that presents serious challenges to the successful treatment of staphylococcal infections of companion animals.

OBJECTIVES

The objective of this document is to provide harmonized recommendations for the diagnosis, prevention and treatment of meticillin-resistant staphylococcal infections in dogs and cats.

METHODS

The authors served as a Guideline Panel (GP) and reviewed the literature available prior to September 2016. The GP prepared a detailed literature review and made recommendations on selected topics. The World Association of Veterinary Dermatology (WAVD) provided guidance and oversight for this process. A draft of the document was presented at the 8th World Congress of Veterinary Dermatology (May 2016) and was then made available via the World Wide Web to the member organizations of the WAVD for a period of three months. Comments were solicited and posted to the GP electronically. Responses were incorporated by the GP into the final document.

CONCLUSIONS

Adherence to guidelines for the diagnosis, laboratory reporting, judicious therapy (including restriction of use policies for certain antimicrobial drugs), personal hygiene, and environmental cleaning and disinfection may help to mitigate the progressive development and dissemination of MDR staphylococci.

In vitro transfer of methicillin resistance determinants mecA from methicillin resistant Staphylococcus aureus (MRSA) to methicillin susceptible Staphylococcus aureus (MSSA)

Background

Staphylococcus aureus more than any other human pathogen is a better model for the study of the adaptive evolution of bacterial resistance to antibiotics, as it has demonstrated a remarkable ability in its response to new antibiotics. This study was designed to investigate the in vitro transfer of mecA gene from methicillin resistant S. aureus to methicillin susceptible S. aureus.

Result

The recipient transconjugants were resistant to erythromycin, cefpodoxime and were mecA positive. PCR amplification of mecA after mix culture plating on Luria Bertani agar containing 100 μg/mL showed that 75% of the donor and 58.3% of the recipient transconjugants were mecA positive. Additionally, 61.5% of both the donor cells and recipient transconjugants were mecA positive, while 46.2% and 41.75% of both donor and recipient transconjugants were mecA positive on LB agar containing 50 μg/mL and 30 μg/mL respectively.

Conclusion

In this study, the direction of transfer of phenotypic resistance as well as mecA was observed to have occurred from the donor to the recipient strains. This study affirmed the importance of horizontal transfer events in the dissemination of antibiotics resistance among different strains of MRSA.

Zoonoses in Veterinary Students: A Systematic Review of the Literature

BACKGROUND

Veterinary students face diverse potential sources of zoonotic pathogens since the first years of their academic degree. Such sources include different animal species and pathologic materials which are used at university facilities as well as commercial clinics, farms and other external facilities.

OBJECTIVES

The present study utilizes a systematic review of the literature to identify zoonoses described in veterinary students.

DATA SOURCES

Web of Science and PubMed.

RESULTS

Of the 1,254 titles produced by the bibliographic search, 62 were included in this review. Whereas 28 of these articles (45.2%) described individual cases or outbreaks, the remaining 34 (54.8%) reported serological results. The zoonotic etiological agents described were bacteria, in 39 studies (62.9%), parasites, in 12 works (19.4%), virus, in 9 studies (14.5%) and fungi, in 2 (3.2%) of the selected articles. The selected literature included references from 24 different countries and covered the time period of the last 55 years.

LIMITATIONS

The fact that common cases of disease or cases of little clinical importance without collective repercussions are not usually published in peer-reviewed journals limits the possibility to reach conclusions from a quantitative point of view. Furthermore, most of the selected works (66.1%) refer to European or North American countries, and thus, the number of cases due to pathogens which could appear more frequently in non-occidental countries might be underestimated.

CONCLUSIONS/IMPLICATIONS

The results of the present systematic review highlight the need of including training in zoonotic diseases since the first years of Veterinary Science degrees, especially focusing on biosecurity measures (hygienic measures and the utilization of the personal protective equipment), as a way of protecting students, and on monitoring programs, so as to adequately advise affected students or students suspicious of enduring zoonoses.

Livestock-associated meticillin-resistant Staphylococcus aureus in Asia: an emerging issue?

In addition to being a human pathogen, Staphylococcus aureus causes an array of infections in economically important livestock animals, particularly pigs. In Asia, there have been few reports on livestock-associated meticillin-resistant S. aureus (LA-MRSA), mostly from developed countries, with very few data available from resource-limited countries, not because of low prevalence but probably due to a shortage of diagnostic facilities. Unlike the wide spread of sequence type 398 (ST398) LA-MRSA in European countries and North America, ST9 predominates in most Asian countries. The prevalence of LA-MRSA among pigs in Asian countries varied widely (0.9-42.5%). The prevalence may vary by geographic location, age of pigs and sampling methodologies. Among pig farmers, the prevalence of nasal MRSA colonisation varied from 5.5% in Malaysia to 15% in China and 19.2% in Taiwan. Although most LA-MRSA isolates in Asia are of the same ST, molecular characteristics are not all the same. Dominant isolates in China were characterised as spa type t899-SCCmec III and t899-SCCmec IVb or V for isolates in Hong Kong, and t899-untypeable SCCmec for Taiwan. Dominant isolates in Malaysia were spa type t4358-SCCmec V and t337-SCCmec IX for isolates in Thailand. In addition, MRSA ST221 was reported in Japan and MRSA ST398 was isolated from commercial pigs in South Korea. Attention should be paid because pigs could become an important reservoir for MRSA and spread them to humans, as observed in many countries. There is a potential risk from the livestock reservoir to community and hospitals.