Molecular Epidemiology of Salmonella enterica in Poultry in South Africa Using the Farm-to-Fork Approach

The presence of the zoonotic pathogen Salmonella in the food supply chain poses a serious public health threat. This study describes the prevalence, susceptibility profiles, virulence patterns, and clonality of Salmonella from a poultry flock monitored over six weeks, using the farm-to-fork approach. Salmonella was isolated using selective media and confirmed to the genus and species level by real-time polymerase chain reaction (RT-PCR) of the invA and iroB genes, respectively. Antimicrobial susceptibility profiles were determined using Vitek-2 and the Kirby–Bauer disk diffusion method against a panel of 21 antibiotics recommended by the World Health Organisation Advisory Group on Integrated Surveillance of Antimicrobial Resistance (WHO-AGISAR). Selected virulence genes were identified by conventional PCR, and clonality was determined using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). Salmonella was present in 32.1% of the samples: on the farm (30.9%), at the abattoir (0.6%), and during house decontamination (0.6%). A total of 210 isolates contained the invA and iroB genes. Litter, faeces, and carcass rinsate isolates were classified as resistant to cefuroxime (45.2%), cefoxitin (1.9%), chloramphenicol (1.9%), nitrofurantoin (0.4%), pefloxacin (11.4%), and azithromycin (11%). Multidrug resistance (MDR) was observed among 3.8% of the isolates. All wastewater and 72.4% of carcass rinsate isolates were fully susceptible. All isolates harboured the misL, orfL, pipD, stn, spiC, hilA, and sopB virulence genes, while pefA, spvA, spvB, and spvC were absent. In addition, fliC was only present among the wastewater isolates. Various ERIC-PCR patterns were observed throughout the continuum with different subtypes, indicating the unrelated spread of Salmonella. This study concluded that poultry and the poultry environment serve as reservoirs for resistant and pathogenic Salmonella. However, there was no evidence of transmission along the farm-to-fork continuum.

Comprehensive analysis of imipenemase (IMP)-type metallo-Beta-lactamase showing global distribution threating Asia

Antibiotic resistance, particularly beta-lactam resistance, is a major problem worldwide. Imipenemase or IMP-type metallo-beta-lactamase (MBL) has become a more prominent enzyme, especially in Asia, since it was discovered in the 1990s in Japan. There are currently more than 91 variants of IMP-type enzymes. The most commonly identified variant of IMP-type enzymes is IMP-1 variant. IMP-type MBLs have been identified in more than 10 species in Enterobacterales. Pseudomonas aeruginosa is the most frequent carrier of IMP-type enzymes worldwide. In Asia, IMP-type MBLs have been distributed in many countries in the region. This work investigated a variety of currently available IMP-type MBLs in both global level and regional level. Out of 88 variants of IMP-type MBLs reported worldwide, only 32 variants were found to have susceptibility profiles. Most of the IMP-type MBLs were resistant to Carbapenems, especially Imipenem and Meropenem, followed by the 3rd generation cephalosporins, and interestingly, monobactams. Our results comprehensively indicated the distribution of IMP-type MBLs in Asia and raised the awareness of the situation of antimicrobial resistance in the region.

Antimicrobial Susceptibility of Neisseria gonorrhoeae in Adult Patients Seeking Care at Military Hospitals in Thailand From 2014 to 2020

ABSTRACT Introduction The effective dual antibiotics ceftriaxone (CRO) and azithromycin (AZM) have successfully treated Neisseria gonorrhoeae (GC) infection, however, the CRO- and AZM-resistant strains have been sporadically detected globally and in Thailand. Furthermore, there are no currently antimicrobial susceptibility profiles of the GC isolates obtained from soldiers reported in Thailand. Hence, this is the first study to describe the antimicrobial susceptibility profiles of GC isolates obtained from predominately soldiers who seeking care at Military Camp Hospitals, in Thailand from 2014 to 2020. Materials and Methods A total of 624 symptomatic gonococcal samples were received from 10 military hospitals during 2014-2020. They were collected from urethral swabs and inoculated into selective media. The suspected GC isolates were subcultured and presumptively identified using conventional microbiology techniques. Antimicrobial susceptibility test was performed by Etest to determine minimal inhibitory concentration (μg/mL) against AZM, benzylpenicillin, cefepime, cefixime, ceftriaxone (CRO), ciprofloxacin, spectinomycin, and tetracycline using the criteria outlined in the Clinical and Laboratory Standards Institute guidelines. This study was approved by Institutional Review Board, Royal Thai Army Medical Department under protocol number S036b/56 and Walter Reed Army Institute of Research, and Silver Spring, MD under protocol number WR #2039. Results A total of 624 samples were collected from symptomatic gonococcal infectious patients with 91.5% (571/624) of samples obtained from soldiers. Of those, 78% (488/624) were identified as GC and 92% (449/488) of them were isolated from soldiers. All GC samples collected were susceptible to CRO (first-line treatment) with only one GC isolate identified as non-susceptible to cefepime and three isolates identified as non-susceptible to AZM. Conclusion The recommended dual treatment of GC infections with CRO and AZM is currently an effective empirical treatment for patients who are seeking care at military hospitals in Thailand. Nevertheless, cefepime is a fourth-generation cephalosporin with documented high activity against GC strains equal to other “third-generation” cephalosporins such as CRO. Due to the active duty of military personnel, they concerned about the confidentiality and frequently seek treatment at civilian clinics. Additionally, due to the availability of antibiotics over the counter in Thailand, many choose the option to self-medicate without a physician’s prescription. These could be subsequently driven the gradual increase of multidrug-resistant gonococcal strains throughout the country. Thus, the GC surveillance would be needed for further Force Health Protection and public health authorities in response to the drug-resistant GC threats.

Occurrence of Antibiotic-Resistant Staphylococcus spp. in Orange Orchards in Thailand

Background: The widespread indiscriminate application of antibiotics to food crops to control plant disease represents a potential human health risk. In this study, the presence of antibiotic-resistant staphylococci associated with workers and orange orchard environments was determined. A total of 20 orchards (orange and other fruits) were enrolled in the study. Trees in the orange orchards were treated with ampicillin on a pre-determined schedule. Environmental samples (n = 60) included soil, water, and oranges; 152 hand and nasal samples were collected from 76 healthy workers. Antibiotic susceptibility profiles were determined for all staphylococcal isolates. Results: This investigation revealed that of the total Staphylococcus spp. recovered from the orange orchard, 30% (3/10) were resistant to erythromycin, 20% (2/10) were resistant to ampicillin, and 20% (2/10) resistant to both erythromycin and ampicillin. Conclusion: The application of antibiotics to orange trees in open production environments to halt the spread of bacterial disease presents risks to the environment and creates health concerns for Thai farmers using those agents. ARB on crops such as oranges may enter the global food supply and adversely affect public health.

Occurrence and Antimicrobial Susceptibility Profiles of Streptococcus equi subsp. zooepidemicus Strains Isolated from Mares with Fertility Problems

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus), is a β-hemolytic Streptococcus belonging to the Lancefield group C; it is a rare human pathogen, but in horses, it is frequently associated with endometritis. This study aimed to isolate S. zooepidemicus strains, associated with bacterial endometritis in mares, and to define their antimicrobial resistance profile. Twenty-three isolates were recovered from one hundred ninety-six equine uterine swabs (11.7%). Bacterial identification was carried out by Api 20 Strep and confirmed by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS), while antimicrobial susceptibility testing was performed by disk diffusion method on Muller Hinton agar plates. The antibiotic resistance profiles of the isolates revealed a high percentage of resistance to amikacin (95.6%), ampicillin (73.9%) and tetracycline (69.6%), while ceftiofur and ceftriaxone were highly effective with 82.6% and 78.3% of the isolates inhibited, respectively. An intriguing value of resistance to penicillin (34.8%), which represents the first-choice antibiotic in equine S. zooepidemicus infections, was observed. Furthermore, a high prevalence of multidrug-resistant strains (82.6%) was recorded. Continuous surveillance of this potential zoonotic pathogen and an appropriate antimicrobial stewardship program with the promotion of correct use of antimicrobials, after a proper diagnosis, are needed to allow an effective therapy.

Antifungal Resistance in Clinical Isolates of Candida glabrata in Ibero-America

In different regions worldwide, there exists an intra-and inter-regional variability in the rates of resistance to antifungal agents in Candida glabrata, highlighting the importance of understanding the epidemiology and antifungal susceptibility profiles of C. glabrata in each region. However, in some regions, such as Ibero-America, limited data are available in this context. Therefore, in the present study, a systematic review was conducted to determine the antifungal resistance in C. glabrata in Ibero-America over the last five years. A literature search for articles published between January 2015 and December 2020 was conducted without language restrictions, using the PubMed, Embase, Cochrane Library, and LILACS databases. The search terms that were used were “Candida glabrata” AND “antifungal resistance” AND “Country”, and 22 publications were retrieved from different countries. The use of azoles (fluconazole, itraconazole, voriconazole, posaconazole, isavuconazole, ketoconazole, and miconazole) varied between 4.0% and 100%, and that of echinocandins (micafungin, caspofungin, and anidulafungin) between 1.1% and 10.0%. The limited information on this subject in the region of Ibero-America emphasizes the need to identify the pathogens at the species level and perform antifungal susceptibility tests that may lead to the appropriate use of these drugs and the optimal doses in order to avoid the development of antifungal resistance or multi-resistance.

Candida species cause vulvovaginitis and resistance to antifungals used for treatment

In this study were identified Candida species from vaginal secretion isolates, evaluated their in vitro antifungal susceptibilities, and correlated these features with antifungal agents prescribed for patients assisted in a primary care service. Species identification by Polymerase Chain Reaction showed that 36.5% of isolates were characterized as non-C. albicans species. In antifungal susceptibility tests most isolates were susceptible to ketoconazole, fluconazole, and itraconazole, although between 40% and 50% of isolates show resistance or dose-dependent susceptibility to miconazole and nystatin, respectively. Analysis of drugs prescribed to patients revealed that 34.2% of the isolates were considered resistant to agents used in treatment. Several Candida species can cause vulvovaginitis and exhibit different susceptibility profiles to antifungal drugs used in treatment. The identification of Candida species is relevant and useful to the epidemiological management of infections. The antifungal susceptibility test may also be useful for choosing most effective drug treatment for each patient.

Molecular surveillance of resistance to pyrethroids insecticides in Colombian Aedes aegypti populations

Introduction In Colombia, organochloride, organophosphate, carbamate, and pyrethroid insecticides are broadly used to control Aedes aegypti populations. However, Colombian mosquito populations have shown variability in their susceptibility profiles to these insecticides, with some expressing high resistance levels. Materials and methods In this study, we analyzed the susceptibility status of ten Colombian field populations of Ae. aegypti to two pyrethroids; permethrin (type-I pyrethroid) and lambda-cyhalothrin (type-II pyrethroid). In addition, we evaluated if mosquitoes pressured with increasing lambda-cyhalothrin concentrations during some filial generations exhibited altered allelic frequency of these kdr mutations and the activity levels of some metabolic enzymes. Results Mosquitoes from all field populations showed resistance to lambda-cyhalothrin and permethrin. We found that resistance profiles could only be partially explained by kdr mutations and altered enzymatic activities such as esterases and mixed-function oxidases, indicating that other yet unknown mechanisms could be involved. The molecular and biochemical analyses of the most pyrethroid-resistant mosquito population (Acacías) indicated that kdr mutations and altered metabolic enzyme activity are involved in the resistance phenotype expression. Conclusions In this context, we propose genetic surveillance of the mosquito populations to monitor the emergence of resistance as an excellent initiative to improve mosquito-borne disease control measures.

Distinguishing Relapse From Reinfection With Whole-Genome Sequencing in Recurrent Pulmonary Tuberculosis: A Retrospective Cohort Study in Beijing, China

Background: Tuberculosis recurrence is still a major problem for the control of tuberculosis, and the cause of the recurrence is still unclear.Methods: We retrospectively recruited 68 pairs of samples of Mycobacterium tuberculosis (MTB) from recurrent TB cases in Beijing Chest Hospital between January 2008 and December 2019. The whole-genome sequencing was conducted to analyze single-nucleotide polymorphism (SNP) and to identify whether recurrent disease was due to relapse or reinfection. The BACTEC MGIT was performed to compare differences in drug susceptibility profiles between two episodes.Results: 62 (91.2%) out of 68 confirmed recurrence were due to relapse, whereas the remaining six (8.8%) were due to reinfection. And there was a strong association between earlier relapse and underlying chronic diseases. In addition, the MTB isolates from non-diabetic patients had a higher mutation rate than those from diabetic patients. A community transmission was also identified in our cohort. Levofloxacin resistance was the most frequently observed drug resistance for 12.9% relapse cases.Conclusion: The relapse of a previous episode in Beijing. The underlying chronic diseases are associated with an earlier TB relapse. MTB isolates were more prone to develop levofloxacin resistance than moxifloxacin resistance after FQ exposure. The patients at high-risk for relapses deserve more careful investigation.