Determination of staphylococcal exotoxins, SCCmec types, and genetic relatedness of Staphylococcus intermedius group isolates from veterinary staff, companion animals, and hospital environments in Korea

The Staphylococcus (S.) intermedius group (SIG) has been a main research subject in recent years. S. pseudintermedius causes pyoderma and otitis in companion animals as well as foodborne diseases. To prevent SIG-associated infection and disease outbreaks, identification of both staphylococcal exotoxins and staphylococcal cassette chromosome mec (SCCmec) types among SIG isolates may be helpful. In this study, it was found that a single isolate (one out of 178 SIG isolates examined) harbored the canine enterotoxin SEC gene. However, the S. intermedius exfoliative toxin gene was found in 166 SIG isolates although the S. aureus-derived exfoliative toxin genes, such as eta, etb and etd, were not detected. SCCmec typing resulted in classifying one isolate as SCCmec type IV, 41 isolates as type V (including three S. intermedius isolates), and 10 isolates as non-classifiable. Genetic relatedness of all S. pseudintermedius isolates recovered from veterinary staff, companion animals, and hospital environments was determined by pulsed-field gel electrophoresis. Strains having the same band patterns were detected in S. pseudintermedius isolates collected at 13 and 18 months, suggesting possible colonization and/or expansion of a specific S. pseudintermedius strain in a veterinary hospital.     

Low Rate of Methicillin‐resistant Coagulase‐positive Staphylococcal Colonization of Veterinary Personnel in Hong Kong

Elevated rates of methicillin‐resistant Staphylococcus aureus (MRSA) carriage have been reported in veterinary personnel, suggesting an occupational colonization risk. Hong Kong veterinary personnel (n = 150) were sampled for coagulase‐positive staphylococci (CPS) nasal colonization. Risk factors for colonization were assessed by questionnaire. Isolates were identified and antibiotic susceptibility determined. All CPS isolates were investigated for mecA carriage, SCCmec type and PVL genes. Two subjects were colonized with methicillin‐resistant CPS: one with MRSA (spa type t002 (CC5), SCCmec type II) and one with methicillin‐resistant Staphylococcus pseudintermedius (MRSP) (MLST type ST71, SCCmec type II‐III). MLST type ST71 S. pseudintermedius strain is the predominant MRSP clone circulating in dogs in Europe and in Hong Kong. The low MR‐CPS colonization rate may be associated with low levels of large animal exposure or low rates of MRSA colonization of companion animals in Hong Kong. Colonization with non‐aureus CPS, which may cause human infection, must also be considered in veterinary personnel.     

Prevalence of methicillin-resistant staphylococci in canine pyoderma cases in primary care veterinary practices in Canada: A preliminary study

Pyoderma in dogs is most commonly caused by Staphylococcus spp., and significant emergence of methicillin resistance in staphylococcal pyoderma has been reported. This preliminary study of the prevalence of methicillin resistance in canine pyoderma cases in Canadian primary care veterinary practices revealed that methicillin-resistant Staphylococcus spp. were present in 12.1% of 149 staphylococcal positive skin culture cases.     

Dissimilarity of ccrAB gene sequences between methicillin-resistant Staphylococcus epidermidis and methicillin-resistant Staphylococcus aureus among bovine isolates in Korea

The sequences of the ccrAB genes from bovine-, canine- and chicken-originating methicillin-resistant Staphylococcus (S.) epidermidis (MRSE) and bovine methicillin-resistant Staphylococcus (S.) aureus (MRSA) were compared to investigate the frequency of intra-species horizontal transfer of the staphylococcal cassette chromosome mec (SCCmec) complex. Nineteen MRSE strains were isolated from bovine milk, chickens, and dogs, and their genetic characteristics were investigated by multilocus sequence typing and SCCmec typing. Among the animal MRSE strains, the most frequent SCCmec type was type IV, which consisted of the type B mec complex and ccrAB type 2. The ccrA2 and ccrB2 genes were sequenced from the bovine, chicken and canine MRSE strains and compared with those of the bovine MRSA strains. The sequences generally clustered as MRSA and MRSE groups, regardless of the animal source. Additionally, no bovine MRSE sequence was associated with the bovine MRSA groups. Although most of the bovine MRSE and MRSA isolates possessed SCCmec type IV sequences, our results suggest that the intra-species gene transfer of the SCCmec complex between bovine S. aureus and bovine S. epidermidis strains is not a frequent event.     

Methicillin-resistant Staphylococcus aureus in horses at a veterinary teaching hospital: frequency, characterization, and association with clinical disease

Methicillin-resistant Staphylococcus aureus (MRSA) is an emerging equine pathogen. To attempt to control nosocomial and zoonotic transmission, an MRSA screening program was established for all horses admitted to the Ontario Veterinary College Veterinary Teaching Hospital, whereby nasal screening swabs were collected at admission, weekly during hospitalization, and at discharge. MRSA was isolated from 120 (5.3%) of 2,283 horses: 61 (50.8%) at the time of admission, 53 (44.2%) during hospitalization, and 6 from which the origin was unclear because an admission swab had not been collected. Clinical infections attributable to MRSA were present or developed in 14 (11.7%) of 120 horses. The overall rate of community-associated colonization was 27 per 1,000 admissions. Horses colonized at admission were more likely to develop clinical MRSA infection than those not colonized at admission (OR 38.9, 95% CI 9.49 160, P < 0.0001). The overall nosocomial MRSA colonization incidence rate was 23 per 1,000 admissions. The incidence rate of nosocomial MRSA infection was at the rate of 1.8 per 1,000 admissions, with an incidence density of 0.88 per 1,000 patient days. Administration of ceftiofur or aminoglycosides during hospitalization was the only risk factor associated with nosocomial MRSA colonization. MRSA screening of horses admitted to a veterinary hospital was useful for identification of community-associated and nosocomial colonization and infection, and for monitoring of infection control practices.     

Detection of bacterial contamination and DNA quantification in stored blood units in 2 veterinary hospital blood banks

Blood transfusions in veterinary medicine have become increasingly more common and are now an integral part of lifesaving and advanced treatment in small and large animals. Important risks associated with transfusion of blood products include the transmission of various infectious diseases. Several guidelines suggest what infectious agents to screen for in canine and feline transfusion medicine. However, while the risk of bacterial contamination of blood products during storage and administration has not been documented in veterinary medicine, it has emerged as a cause of morbidity and mortality in human transfusion medicine. Clinical experience shows that the majority of blood component bacterial contaminations are caused by only a few species. Unlike other types of bacteria, psychrotolerant species like Pseudomonas spp. and Serratia spp. can proliferate during the storage of blood units at 4°C from a very low titer at the time of blood collection to a clinically significant level (> 10⁵ CFU/mL) causing clinical sepsis resulting from red blood cell concentrate transfusions in human medicine. The purpose of this report was to describe the detection and quantification procedures applied in 4 cases of bacterial contamination of canine and feline blood units, which suggest the need for further investigations to optimize patients’ safety in veterinary transfusion medicine.     

Bacteria and antibiotic resistance detection in fractures of wild birds from wildlife rehabilitation centres in Spain

Anatomic adaptations make birds more prone to open fractures with exposed bone parts losing vascularization. As a result of this exposure, fractures are colonized by different microorganisms, including different types of bacteria, both aerobic and anaerobic, causing osteomyelitis in many cases. For this reason, antibiotic treatment is common. However, carrying out antibiotic treatment without carrying out a previous antibiogram may contribute to increased resistance against antibiotics, especially in migratory wild birds. In this paper, bacterial counts regarding fracture type, bacterial identification and antibiotic resistance have been analysed in wild birds from wildlife rehabilitation centres in Spain. The results obtained showed that open fractures had higher bacterial counts (CFU/mL) than closed ones. Bacteria in family Enterobacteriaceae, identified were Escherichia spp., Enterobacter spp., Shigella spp., Hafnia alvei, Proteus mirabilis, Leclercia adecarboxylata and Pantoea agglomerans. Other bacteria present in wild birds’ fractures were Aeromonas spp., Enterococcus spp. Bacillus wiedmannii and Staphylococcus sciuri. All species found presented resistance to at least one of the antibiotics used. Wild birds can be implicated in the introduction, maintenance and global spreading of antibiotic resistant bacteria and represent an emerging public health concern. Results obtained in this paper support the idea that it is necessary to take this fact into account before antibiotic administration to wild animals, since it could increase the number of bacteria resistant to antibiotics.     

Blood thiamine levels in clinically normal goats and goats with suspected polioencephalomalacia

Abstract

AIMS: To identify and describe culture and antimicrobial resistance (AMR) patterns in bacteria isolated from canine urinary samples submitted to a New Zealand veterinary diagnostic laboratory.

METHODS: Records from a veterinary diagnostic laboratory were examined for bacterial isolates cultured from canine urine samples between January 2005 and December 2012. Culture and susceptibility results were compiled with information on the age, sex and breed of dog. Repeat submissions were removed. Susceptibility was assessed using results of the Kirby-Bauer disk diffusion method, for a standard panel including amoxicillin-clavulanic acid (AMC), cefovecin (from 2010–2012), cephalothin, clindamycin, enrofloxacin and trimethoprim-sulphonamide (TMS).

RESULTS: A total of 5,786 urine samples were submitted for analysis, and 3,135 bacterial isolates were cultured from 2,184 samples. Of these 3,135 isolates, 1,104 (35.2%) were Escherichia coli, 442 (14.1%) were Staphylococcus spp., 357 (11.4%) Proteus mirabilis and 276 (8.8%) were Enterococcus spp. The frequency of culture-positive samples increased with increasing age in both female and male dogs (p<0.001). The percentage of E. coli isolates resistant to AMC and cephalothin increased between 2005 and 2012 (p<0.001), as did resistance to enrofloxacin (p=0.022), but there was no change in resistance to TMS (p=0.696). Enrofloxacin was the antimicrobial with the least resistance shown by the four most common bacteria isolated during the course of the study.

CONCLUSIONS AND CLINICAL RELEVANCE: The results of this study provide important regional information regarding the prevalence of bacterial uropathogens and their susceptibility patterns. There was an increase in resistance to some commonly used antimicrobials in the treatment of urinary tract infections. Having access to regional antimicrobial susceptibility results is crucial when forming guidelines for the use of antimicrobials for the treatment of urinary tract infections. Given changes in practising habits and antimicrobial usage over time, ongoing monitoring and surveillance of resistance in pathogens is needed.     

Prevalence,species distribution and antimicrobial resistance patterns of methicillin-resistant staphylococci in Lithuanian pet animals

Background

The bacterial genus Staphylococcus consists of many species that causes infections in pet animals. Antimicrobial resistant staphylococci cause infections that are difficult to treat and they are important from the point of one health perspective. The aim of this study was to determine the prevalence of methicillin-resistant Staphylococcus (MRS) species, including methicillin-resistant S. aureus (MRSA) in diseased pet animals (Group A) and kennel dogs (Group B) in Lithuania and to characterize the isolates according to their antimicrobial resistance.

Results

Twenty-one MRS isolates were obtained from 395 clinical samples (5.3 %; CI 95 % 3.5-8.0) of Group A animals. Sixteen, four and one isolates were from dogs, cats and a pet rabbit, respectively. The mecA gene was present in 20 isolates, whereas one isolate was positive for the mecC gene. Twenty-one MRS isolates (20.0 %; CI 95 % 13.5-28.6) were obtained from the vagina of female dogs (n = 105) (Group B). All isolates carried the mecA gene. Twelve MRS species were isolated of which S. pseudintermedius was the most common (18/42) followed by S. haemolyticus (8/42) and S. lentus (4/42). MRSA was not found. All MRS strains were susceptible to vancomycin, linezolid, daptomycin and quinupristin/dalfopristin. Resistance to tetracycline (16/21), clindamycin (15/21) and erythromycin (14/21) was the most common types of resistance in Group A animals. Three isolates also demonstrated resistance to rifampin. Resistance toward gentamicin (16/21), ciprofloxacin (15/21), macrolides (15/21) and tetracycline (12/21) was the most common in kennel dogs (Group B). The most common genes encoding resistance to antimicrobials (excluding beta-lactams) in isolates from Group A pets were tetK (21/42), aph(3′)-IIIa (11/42) and aac(6'')-Ie-aph(2'''')-Ia (9/42).

Conclusions

A wide range of MRS species were found in pet animals in Lithuania. MRSA was not found.     

Detection of methicillin‐resistant Staphylococcus aureus (MRSA) in the microbial flora from the conjunctiva of healthy donkeys from Sicily (Italy)

Objective To describe the bacterial flora present in the normal conjunctiva of donkeys from Sicily (Italy). Animals studied A total of 46 healthy donkeys housed in 3 locations within the territory of Palermo (Sicily, Italy) were studied. Donkeys ranged from 2 to 13 years of age, with a median age of 6 years. Procedures Forty‐six conjunctival swabs were obtained from both eyes of each animal, and specimens were cultured for aerobic bacteria. Furthermore, the antimicrobial activity of methicillin (1 μg) and oxacillin (5 μg) on Staphylococcus spp. isolates was evaluated, and a specific PCR assay, which allows the detection of mecA gene specific for methicillin‐resistant Staphylococcus aureus (MRSA) strains, was performed. Results Forty of 46 (86.9%) donkeys were positive for bacteria. Eighty bacterial isolates, representing 9 bacteria genera, were successfully cultured. The most frequently recovered bacterial genus was Staphylococcus (52/80 isolates; 65%). Several strains (20/80 isolates; 25%) belonging to the Enterobacteriaceae family were also isolated, among which the most frequently isolated genus was Enterobacter (eight isolates). Of the 52 Staphylococcus spp. isolates, 14 (26.9%) strains were oxacillin/methicillin resistant. The mecA gene was detected in 6/52 (11.5%) strains. Conclusions This study contributes to the knowledge about normal ocular flora and MRSA occurrence in donkey farms in Sicily.     

Streptococcus spp. and related bacteria: Their identification and their pathogenic potential for chronic mastitis – A molecular approach

Streptococcus spp. and related bacteria form a large group of organisms which are associated with bovine intramammary Infections (IMI). Some of them are the well-known mastitis pathogens Streptococcus uberis and Streptococcus agalactiae. In addition, there are a considerable number of these gram-positive, catalase-negative cocci (PNC) with unclear mastitic pathogenicity such as Aerococcus viridans which make the conventional diagnostics of PNC difficult. One diagnostic, API 20 Strep (API, Biomérieux) is recommended which, as a phenotypic assay, involves a series of miniaturized biochemical tests. Recently, preference is given to genotypic identification methods. In particular, sequencing of the 16S rRNA gene allows highly reproducible and accurate identification of bacteria and permits discovery of novel, clinically relevant bacteria. As a consequence, the aim of the present study was to compare identification of IMI-associated PNC by the API method as well as by sequencing of their 16S rRNA gene (16S). Furthermore, the correlation of these bacteria to bovine chronic mastitis and their phylogeny was investigated.102 PNC isolated from single quarter milk samples were identified by API and 16S sequencing. Considering Streptococcus uberis, Streptococcus dysgalactiae subsp. dysgalactiae and Streptococcus agalactiae, both methods generated fully concordant results. In contrast, a very high disconcordance was observed for most of the other PNC, in particular Enterococcus spp., Aerococcus viridans and the viridans streptococci were shown as apathogenic. Lactococcus garvieae was found to be an opportunistic pathogen causing IMI during late lactation. In addition, PNC isolated from milk were frequently observed together with other bacteria, in particular with Staphylococcus spp. In these cases, the levels of somatic cell counts (SCC) were determined by the specific PNC present in the sample. Considering PNC phylogeny based on 16S sequencing, 3 major clusters were observed. They included all the common mastitis pathogens (cluster I), the Lactococcus spp., Enterococcus spp. and Aerococcus spp. (cluster II) and all the viridans streptococci (cluster III).     

Identification,occurrence and clinical findings of canine hemoplasmas in southern Brazil

Hemoplasmas are ubiquitous pleomorphic and epicellular bacteria detected in erythrocytes in several species. In Brazil, studies on hemoplasmas have not included information on occurrence, clinical signs, and risk factors in dogs. This paper investigates the occurrence of hemoplasmas in dogs, focusing on risk factors and clinical status. Conventional PCR for the four types of canine hemoplasmas was performed in 331 blood samples collected from dogs clinically treated at a teaching veterinary hospital. Of all samples, 17/331 (5.1%) were positive for Mycoplasma haemocanis and 6/331 (1.8%) were positive for a ‘Candidatus Mycoplasma haemominutum-like’ organism. Risk factors included the presence of vectors, old age, dog bite wounds, and neoplastic diseases. In the multivariate analysis, a 4.40 odds ratio in dogs with vector-borne diseases indicated risk for hemoplasmosis. There was correlation between hemoplasma infection and neoplastic disease, suggesting that neoplastic conditions are a risk factor for hemoplasma infection in dogs.     

Investigation of bacterial microorganisms in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Beijing, China

Objective To determine the bacterial microorganisms in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Beijing, China. The effect of breed, sex and age of dogs and season on the presence or absence of bacteria in the conjunctival sac of clinically normal dogs was evaluated. Sample population This investigation included 240 healthy dogs, 27 dogs with unilateral corneal ulcer and one dog with bilateral corneal ulcer. Procedure The 480 samples from healthy dogs and the 29 samples from dogs with ulcerative keratitis were incubated in an aerobic and 5% CO₂ environment at 37 °C for 48 h. Logistic regression analysis was performed. Statistical significance was set at P < 0.01. Results Of 480 normal eyes, Staphylococcus spp. were the most frequently isolated organisms (40.29%). Neisseria spp. (11.47%) were the next most frequently isolated organisms, followed by Corynebacterium spp. (9.4%). Of 29 eyes with ulcerative keratitis, Staphylococcus spp. were also the most frequently isolated bacteria (47.06%). Streptococcus spp. (12.94%) and Pseudomonas spp. (8.24%) were the second and third, respectively. Season (P = 0.002) was a significant factor influencing presence or absence of bacterial microorganisms in the conjunctival sac of normal dogs in Beijing, China, while the effects of breed (P = 0.095), sex (P = 0.588) and age (P = 0.866) of dogs were insignificant. Conclusion Staphylococcus spp. were the most frequently isolated organisms, and S. intermedius predominated in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Beijing, China. The likelihood of detecting bacteria depends on the season.     

Dynamic of nasal colonization by methicillin-resistant Staphylococcus aureus ST398 and ST1 after mupirocin treatment in a family in close contact with pigs

Nasal colonization by methicillin-resistant Staphylococcus aureus (MRSA) was evaluated after a mupirocin treatment in a family previously colonized by MRSA sequence type ST398 and ST1, who lived close to a pig farm. Eight nasal samples were swabbed from each of the four family members on different moments after mupirocin treatment. The efficacy of treatment was low in those family members who worked in the farm, and higher in the remaining two family members with sporadic contact with pigs. In addition, nasal and skin swabs from randomly selected pigs of the farm were taken. MRSA were detected in 33% of pigs tested. All MRSA isolates obtained were characterized by Staphylococcal-Cassette-Chromosome mec (SCCmec) determination, Multilocus-Sequence-Typing (MLST), spa- and agr-typing, Pulsed-field-gel-electrophoresis (PFGE), antimicrobial susceptibility, detection of antimicrobial resistance genes, and toxin gene profiling. Spa-types t011, t1255 and t1197 were detected in humans and animals, with indistinguishable PFGE patterns, suggesting animal to human MRSA transmission. Each spa-type was ascribed to a specific pulsotype. Spa-types t127 and t108 were only detected in MRSA isolates obtained from humans, and t012 only in those from animals. MRSA ST1-t127 isolates and some ST398-t011 and ST398-t1197 isolates presented a multiantimicrobial-resistance phenotype. None of them harbored lukF/lukS, tst, eta and etb virulence genes. This study showed that the efficacy of nasal MRSA decolonization in healthy people with very close contact with pigs is especially low.     

Antimicrobial therapy for multidrug resistant pathogens

Multidrug resistant bacteria are tremendous causes of morbidity and mortality in human medicine, and emerging pathogens in equine medicine. A variety of organisms, such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin resistant Enterococcus spp. (VRE) and multidrug resistant Acinetobacter spp., Pseudomonas spp. and Enterobacteriaceae are of concern in equine medicine. Veterinary practitioners need to be aware of key diagnostic, clinical, therapeutic, epidemiological and infection control aspects to limit the impact of these organisms on the equine, and perhaps human, population.     

Identification of Helicobacter spp. in oral secretions vs. gastric mucosa of stray cats

The definite mode of transmission of Helicobacter infection is largely unknown. This study was carried out primarily, to determine the existence of Helicobacter spp. in the oral secretions of stray cats as one of the possible routes of transmission and secondly, to evaluate the accordance between oral and gastric colonization of Helicobacter spp. in these cats. Forty-three adult stray cats were thus studied for the presence of Helicobacter species by quantitative rapid urease test (RUT), cytology and PCR. Helicobacter spp. were found in the oral secretions and gastric biopsies of 93% and 67.5% of the stray cats, respectively. There was not, however, any agreement observed between Helicobacter colonization at these two locations, at neither genus nor species level. These findings suggest that the oral cavity is routinely exposed to transient forms of bacteria and may temporarily harbor Helicobacter spp. Thus, oral cavity as a source of Helicobacter spp. may act as a reservoir for transmission and may not necessarily reflect the colonization status of the gastric mucosa.     

Vaginal lactic acid bacteria in healthy and ill bitches and evaluation of in vitro probiotic activity of selected isolates

The concentrations of lactic acid bacteria (LAB) in 42 vaginal samples from healthy and ill bitches were determined. Eight isolates belonging to the genera Lactobacillus and Enterococcus were selected and identified and their in vitro antimicrobial activity against canine pathogens and their ability to adhere to canine vaginal epithelial cells were determined. There was no correlation between the concentrations of vaginal LAB and clinical status, body temperature, vaginal pH, or age. Although the animals were either well or suffering from various illnesses, LAB were found in almost every sample, and the selected isolates showed promising probiotic-related features. These findings are significant for the design of strategies for the modulation of vaginal microbiota by vaginal LAB isolates.     

Prevalence and characterization of methicillin-resistant Staphylococcus pseudintermedius from symptomatic companion animals in Northern Italy: Clonal diversity and novel sequence types

The aim of this study was to assess the prevalence, the genotypic diversity, the antimicrobial resistance traits of canine and feline clinical methicillin-resistant Staphylococcus pseudintermedius (MRSP) isolates in a diagnostic laboratory in Italy during 2015-2016.All isolates were characterized by multilocus sequence typing (MLST), staphylococcal cassette chromosome (SCC)-mec typing and staphylococcal protein A (spa)-typing. The resistance profiles were assessed by antimicrobial susceptibility testing and confirmed genotypically by the detection of mecA gene and by microarray analyses.The prevalence of MRSP isolates was high (31.6%). All the strains were multidrug resistant and the most frequent clone was ST71-SCCmec type II-III. These results confirm a high prevalence of MRSP amongst clinical samples from pets in Italy. These isolates show multidrug resistance features that are of concern both in veterinary and human medicine for clinical and epidemiological reasons.     

Helicobacter spp. in the saliva,stomach, duodenum and faeces of colony dogs

The role of Helicobacter spp. infection in canine gastrointestinal disease is unclear and routes of transmission are of epidemiological and zoonotic importance. The aim of this study was to identify Helicobacter spp. in the saliva, stomach, duodenum and faeces of dogs using a multiplex PCR, and to evaluate any attendant histopathological changes. Helicobacter canis was the most common species detected in saliva and faeces and no correlation between the presence of Helicobacter spp. and histopathological changes in either the stomach or duodenum was observed. All dogs examined were co-infected with up to four species of the organism. This is the first time these bacteria have been studied at species level at multiple sites within the canine alimentary tract.     

Prevalence of canine methicillin resistant Staphylococcus pseudintermedius in a veterinary diagnostic laboratory in Italy

The overall prevalence of methicillin-resistant Staphylococcus pseudintermedius (MRSP) was 2% (10/590) among 590 canine specimens submitted to an Italian veterinary diagnostic laboratory during a two-month period, and 21% (10/48) among Staphylococcus intermedius group (SIG) isolates. All methicillin-resistant strains exhibited additional resistance to fluoroquinolones, gentamicin, lincosamides, tetracyclines, and potentiated sulfonamides, belonged predominantly to spa type t02 and harboured SCCmec type II–III cassette.