Coexistence of bla NDM-5 and tet(X4) in international high-risk Escherichia coli clone ST648 of human origin in China.

The emergence of pathogens is conferring resistance to last-resort therapies such as tigecycline, colistin, and carbapenems, limiting the therapeutic options, and raising concerns about the emergence of new "superbugs." This study reports the first incident of a bla NDM-5 and tet(X4) co-harboring Escherichia coli with resistance to carbapenem and tigecycline recovered as the causative agent of a urinary tract infection in a 94-year-old patient. The E. coli strain ECCL209 carries multiple resistance genes [i.e., bla TEM-1B , bla NDM-5, bla CMY-2, aadA22, florR, erm(B), mph(A), erm(42), lnuG, qnrS1, and sul2] and exhibits resistance to almost all clinically used antibiotics. MLST analysis found that the strain belongs to ST648, considered a worldwide high-risk pandemic clone. Moreover, multiple plasmid incompatibility types were detected, i.e., IncHI1A, IncHI1B, IncFII, IncFIA, IncFIB, IncQ1, Col, and IncX4. Genetic analysis revealed that bla NDM-5 and tet(X4) genes were localized on two hybrid plasmids with multiple replicons. Continuous monitoring studies are suggested to quantify the antimicrobial resistance and assess the dissemination of such superbugs into a human healthcare setting.

Methicillin-resistant Staphylococcus aureus (MRSA) isolated from chicken meat and giblets often produces staphylococcal enterotoxin B (SEB) in non-refrigerated raw chicken livers.

Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for several difficult-to-treat infections and staphylococcal food poisoning (SFP). This study was conducted to investigate the prevalence and enterotoxigenicity of MRSA in broiler chicken meat and giblets. A total of 5.5% (8/144) of the examined samples were contaminated with mecA positive/mecC negative MRSA, with staphylococcal counts of approximately 102 colony forming units (CFU)/g in breast, leg and gizzard samples and approximately 3.3 × 103 CFU/g in frozen liver samples. Most MRSA isolates (75%, 6/8) harboured the staphylococcal enterotoxin B (seb) gene. Reverse transcription-PCR (RT-PCR) showed that MRSA isolates initiated SEB production in experimentally contaminated chicken livers within 24 h of storage at temperatures over 8 °C. SEB was maximally produced at 24 °C when the MRSA counts reached 7.3 × 103 ± 1.2 × 103 CFU/g sample homogenate. The current study concludes that the main broiler chicken MRSA isolates in Egypt harbour the seb gene. To mitigate possible SEB production, especially in broiler chicken livers, a maximum "out of refrigeration" time limit should be implemented for cold chain poultry products.

Molecular typing and evaluation of Sidr honey inhibitory effect on virulence genes of MRSA strains isolated from catfish in Egypt.

Fish represent a worldwide significant source of animal protein. In order to investigate the prevalence of MRSA in catfish as well as the inhibitory effect of Sidr honey on virulence genes of MRSA, fish were collected from Bahr Elbaker canal at Sharkia Governorate, Egypt. Swab samples were collected under complete aseptic conditions from internal organs (pancreas, liver, kidney and intestine), gills and skin then subjected to bacteriological examination. A total of 70 S. aureus strains were isolated from catfish, out of them 15 (21.42%) strains were identified as MRSA as a first record in Egypt. PCR was used for detection of meca, coa and spa genes in the isolated MRSA strains before and after the exposure to sidr honey. Before exposure to sider honey, all the selected MRSA strains showed positive results for meca, coa and spa genes with specific amplicon size of 310 bp, 430 bp and 226 bp, respectively. After exposure to sidr honey, MRSA strains showed inhibition of coa and spa genes, but has no effect on meca gene. In addition, scanning electron microscopy was used for detection of the morphological characters of MRSA strains before and after treatment with sidr honey. After exposure of MRSA strains to 30% (w/v) Sidr honey for 48 hours, cells surfaces were observable irregular with the appearance of cell debris. In conclusion, MRSA strains could be isolated from fresh water catfish in Egypt which may be attributed to the contamination of water and fish food. Sider honey showed a significant inhibitory effect on the growth of isolated MRSA strains. Moreover, it could inhibit spa and coa genes. SEM is a valuable tool revealing the abnormal morphological changes that take place in MRSA strains after exposure to Sidr honey.