The asymptomatic ocular surface reservoir of coronavirus disease-19 in infants and retinopathy of prematurity screening during the pandemic.

PURPOSE: This study aimed to evaluate the incidence of conjunctival and pharyngeal swab sample positivity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in asymptomatic preterm and term infants. We aimed to detect asymptomatic carrier potential in infants. MATERIALS AND METHODS: Patients screened for retinopathy of prematurity (ROP) at our clinic between January and June 2021 were recruited for this study. For all study cases, the previous history of possible exposure or contact with SARS-CoV-2, previous history of coronavirus disease-19 (COVID-19), or contact with any COVID-19 case was excluded. None of the patients showed signs of COVID-19 during sample collection. Pharyngeal and conjunctival swab samples were collected before the ophthalmic examination. Nucleic acid isolation from the samples was performed using an automated system. The presence of SARS-CoV-2 RNA in the samples was screened using a real-time polymerase chain reaction kit, and the positive samples were re-evaluated for the variant virus. RESULTS: Among the 127 patients with a median age of 40 weeks (range: 34-86) of postmenstrual age, positivity for SARS-CoV-2 RNA in the pharyngeal and conjunctival samples was 5/127 (3.93%) and 3/127 (2.36%), respectively. Isolated conjunctival positivity was not observed in any of the patients, and all three patients were positive for both conjunctiva and pharynx. CONCLUSION: Asymptomatic infants may be a reservoir for SARS-CoV-2, and conjunctival infection in infants may be a source of virus transmission. Since ROP screening cannot be postponed during the pandemic, caution should be exercised to prevent the spread of the disease.

Prevalence of carbapenemases in Enterobacterales from urine specimens in an university hospital in Istanbul, Turkey.

We aimed to investigate the prevalence of carbapenemases in Enterobacterales strains isolated from urine specimens between July 2019 and July 2020.CIM and modified CIM tests were applied as well as detection of blaOXA-48, blaNDM, blaVIM, blaKPC and blaIMP genes was performed by multiplex PCR.One hundred fifty of 3,242 Enterobacterales strains were found to be carbapenem resistant and 46 were included in the study. Forty five (98%) of the 46 strains included in the study were Klebsiella spp. and one (2%) of them was Escherichia coli. Susceptibility to ceftazidime-avibactam, amikacin and gentamicin was 97%, 11% and 9%, respectively. Forty three (94%) isolates were found positive at 2 and 4 h with CIM test. Forty four (97%) strains were found positive at 4 h and 43 (94%) strains were found positive at 2 h with modified CIM test.While blaOXA-48, blaNDM and blaOXA-48 with blaNDM association were found in Klebsiella spp. isolates in 55%, 27% and 11%, respectively, blaVIM, blaKPC, blaIMP were not found. Only blaOXA-48 and blaNDM-1 were detected in the E. coli strain.None of the investigated genes were detected in three Klebsiella strains but with whole genome analysis the combination of blaOXA-534, blaCMY-99 and blaKPC-3 was found in the first strain, blaOXA-370 in the second strain and no resistance gene was found in the third strain.Ceftazidime-avibactam was found to be active against 97% of strains, and the most common resistance genes were blaOXA-48 and blaNDM-1. Previously undetected resistance genes have been identified in our country.

Simultaneous detection and differentiation of pathogenic and nonpathogenic Leptospira spp. by multiplex real-time PCR (TaqMan) assay.

Leptospirosis, caused by pathogenic Leptospira, is one of the most important zoonoses in the world. Several molecular techniques have been developed for detection and differentiation between pathogenic and saprophytic Leptospira spp. The aim of this study was to develop a rapid and simple assay for specific detection and differentiation of pathogenic Leptospira spp. by multiplex real-time PCR (TaqMan) assay using primers and probes targeting Leptospira genus specific 16S ribosomal RNA gene, the pathogen specific lig A/B genes and nonpathogen Leptospira biflexa specific 23S ribosomal RNA gene. Sixteen reference strains of Leptospira spp. including pathogenic and nonpathogenic and ten other negative control bacterial strains were used in the study. While the 16S primers amplified target from both pathogenic and non-pathogenic leptospires, the ligA/B and the 23S primers amplified target DNA from pathogenic and non-pathogenic leptospires, respectively. The multiplex real-time PCR (TaqMan) assay detection limit, that is, the sensitivity was found approximately 1 x 10(2) cells/ml for ligA/B gene and 23S ribosomal RNA gene, and 10 cells/ml 16S ribosomal RNA. The reaction efficiencies were 83-105% with decision coefficients of more than 0.99 in all multiplex assays. The multiplex real-time PCR (TaqMan) assay yielded negative results with the ten other control bacteria. In conclusion, the developed multiplex real-time PCR (TaqMan) assay is highly useful for early diagnosis and differentiation between pathogenic and non-pathogenic leptospires in a reaction tube as having high sensitivity and specificity.