An Assessment of West Nile and Usutu Viruses' Seroprevalence in Hospitalized Patients: A Preliminary Study on Flavivirus Exposure in Eastern Romania

WNV and USUV are closely related epornitic flaviviruses transmitted by Culex mosquitoes which can cause febrile and neurodegenerative disease in humans. The impact of both viruses on public health has increased in the recent decades.

AIM

The aim of the study was to evaluate the seroprevalence of WNV and USUV in hospitalized patients from eastern Romania who did not show symptoms corresponding to the case definition.

METHODS

Human blood samples from the hospitalized patients were collected in 2015 and from April to September 2019 in Iasi County, Romania. The samples were screened by ELISA for anti-WNV IgG, IgM, and anti-USUV IgG antibodies.

RESULTS

A cumulative seroprevalence of 3.4% was recorded for anti-WNV IgG antibodies and 9.1% for anti-WNV IgM. No sample was positive for anti-USUV antibodies.

CONCLUSION

The cumulative seroprevalence observed provides support for the consideration of WNV as being endemic in the east of Romania. The absence of anti-USUV antibodies may be related to cross-reactivity and cohort size, thus, USUV should be considered in clinical practice and become an objective for active surveillance in Romania.

Antimicrobial Activity of Artemisia dracunculus Oil-Loaded Agarose/Poly(Vinyl Alcohol) Hydrogel for Bio-Applications

In this study, the potential use of Artemisia dracunculus essential oil in bio-applications was investigated. Firstly, the phytochemicals from Artemisia dracunculus were analyzed by different methods. Secondly, the Artemisia dracunculus essential oil was incorporated into the hydrogel matrix based on poly(vinyl alcohol) (PVA) and agar (A). The structural, morphological, and physical properties of the hydrogel matrix loaded with different amounts of Artemisia dracunculus essential oil were thoroughly investigated. FTIR analysis revealed the successful loading of the essential oil Artemisia dracunculus into the PVA/A hydrogel matrix. The influence of the mechanical properties and antimicrobial activity of the PVA/A hydrogel matrix loaded with different amounts of Artemisia dracunculus was also assessed. The antimicrobial activity of Artemisia dracunculus (EO Artemisia dracunculus) essential oil was tested using the disk diffusion method and the time-kill assay method after entrapment in the PVA/A hydrogel matrices. The results showed that PVA/agar-based hydrogels loaded with EO Artemisia dracunculus exhibited significant antimicrobial activity (log reduction ratio in the range of 85.5111-100%) against nine pathogenic isolates, both Gram-positive (S. aureus, MRSA, E. faecalis, L. monocytogenes) and Gram-negative (E. coli, K. pneumoniae, S. enteritidis, S. typhimurium, and A. salmonicida). The resulted biocompatible polymers proved to have enhanced properties when functionalized with the essential oil of Artemisia dracunculus, offering opportunities and possibilities for novel applications.

Clonal Dissemination of Extended-Spectrum Cephalosporin-Resistant Enterobacterales between Dogs and Humans in Households and Animal Shelters of Romania

Faecal carriage of extended-spectrum cephalosporin-resistant (ESC-R) Enterobacterales in healthy pets is a concerning issue. This study aimed to determine the prevalence, genetic background, and potential for interspecies transmission of these bacteria between dogs and humans within the same household (HH) or shelter environment in Romania. Faecal samples (n = 263) collected from healthy dogs (n = 102), their owners (n = 32), as well as dogs (n = 110) and staff (n = 19) from dog shelters, were screened for ESC-R carriage. Clonal relatedness of canine and human Escherichia coli isolates was established using Fourier Transform Infrared Spectroscopy (FTIR), followed by Illumina WGS of selected isolates. The highest prevalence of ESC-R Enterobacterales faecal carriage was identified in staff working at dog shelters (78.9%), followed by dogs from households (44.11%), dog owners (43.7%), and dogs from shelters (27%). FTIR identified 15 clusters of closely related E. coli isolates, including dog and human isolates from the same environment. Co-carriage of ESC-R isolates in both the dog and owner was identified in 12 HHs (37.5%), with two HHs (6%) having both the owner and dog carrying isolates with identical FTIR spectra, phylogroup, resistance genes, and Inc plasmids. Major ExPEC lineages such as ST127, ST10, ST155, and ST88 were detected in human and dog isolates. Our study revealed a high prevalence of faecal ESC-R E. coli carriage in both dogs and humans from Romanian households and shelters, where bidirectional clonal transmission between humans and dogs is likely. Furthermore, we identified ESC-R Enterobacterales co-carriage in people and dogs sharing the same environment using FTIR, demonstrating its value in AMR surveillance for humans and animals.