Epidemiology of viral infections among children undergoing hematopoietic stem cell transplant: Α prospective single-center study.

BACKGROUND: Viral infections are a significant cause of morbidity and mortality in pediatric transplant populations. We analyzed the epidemiology of viral infections in pediatric hematopoietic stem cell transplant (HSCT) patients, including their incidence, associated risk factors, and outcome. METHODS: In a prospective study from September 2011 to September 2015, blood, urine, and stool specimens were monitored weekly from transplantation to day 100 or after if clinically suspected, by use of real-time polymerase chain reaction. Cytomegalovirus (CMV), Epstein-Barr virus (EBV), BK polyomavirus (BKV), Herpes simplex virus-1,2, Varicella zoster virus, Human herpes virus-6,7, and Adenovirus infections were monitored. All children and adolescents who underwent HSCT received long-term follow up in the regular outpatient clinics (range 2-48 months). RESULTS: A total of 192 HSCTs (autologous/allogeneic: 53/139) were performed in 165 subjects (median age: 5.6 years). Viruses most commonly isolated were CMV (46.1%), BKV (25.9%) and EBV (22.6%) and were more frequent in allogeneic versus autologous transplants (P < 0.05). Almost all high-risk allogeneic recipients developed EBV infections post-HSCT. EBV-PTLD was the only cause of death among those who developed viral disease. The factors significantly associated with the development of viral infections were recipient's advanced age, unrelated donor, mismatched graft and use of peripheral blood stem cells grafts. CONCLUSIONS: Viral infections were common among our pediatric recipients. Data suggest that monitoring of viral load may be significant to the prevention of viral disease. Particular demographic and transplantation characteristics were associated with the development of viral infections post-HSCT.

Challenges in antigenic characterization of circulating influenza A(H3N2) viruses during the 2011-2012 influenza season: an ongoing problem?

Genetic and antigenic characterization of 37 representative influenza A(H3N2) virus strains isolated in Greece during the 2011-2012 winter season was performed to evaluate matching of the viruses with the seasonal influenza vaccine strain A/Perth/16/2009. Hemagglutinin gene sequence analysis revealed that all Greek strains clustered within the Victoria/208 genetic clade. Furthermore, substitutions in the antigenic and glycosylation sites suggested potential antigenic drift. Our hemagglutination inhibition (HI) analysis showed that the Greek viruses were Perth/16-like; however, these viruses were characterized as Victoria/208-like when tested at the United Kingdom WHO Collaborating Centre (CC) with HI assays performed in the presence of oseltamivir, a finding consistent with the genetic characterization data. Variability in the HI test performance experienced by other European laboratories indicated that antigenic analysis of the A(H3N2) virus has limitations and, until its standardization, national influenza reference laboratories should include genetic characterization results for selection of representative viruses for detailed antigenic analysis by the WHO CCs.

The Importance of the One Health Concept in Combating Zoonoses.

One Health fundamentally acknowledges that human health is linked to animal health and the environment. One of the pillars One Health is built on is zoonoses. Through the years, zoonotic infections have caused numerous outbreaks and pandemics, as well as millions of fatalities, with the COVID-19 pandemic being the latest one. Apart from the consequences to public health, zoonoses also affect society and the economy. Since its establishment, One Health has contributed significantly to the protection of humans, animals, and the environment, through preparedness, surveillance, and mitigation of such public dangers.

Effectiveness of a Self-Decontaminating Coating Containing Usnic Acid in Reducing Environmental Microbial Load in Tertiary-Care Hospitals.

Surfaces have been implicated in the transmission of pathogens in hospitals. This study aimed to assess the effectiveness of an usnic-acid-containing self-decontaminating coating in reducing microbial surface contamination in tertiary-care hospitals. Samples were collected from surfaces 9 days before coating application, and 3, 10, and 21 days after its application (phases 1, 2, 3, and 4, respectively). Samples were tested for bacteria, fungi, and SARS-CoV2. In phase 1, 53/69 (76.8%) samples tested positive for bacteria, 9/69 (13.0%) for fungi, and 10/139 (7.2%) for SARS-CoV-2. In phase 2, 4/69 (5.8%) samples tested positive for bacteria, while 69 and 139 samples were negative for fungi and SARS-CoV-2, respectively. In phase 3, 3/69 (4.3%) samples were positive for bacteria, 1/139 (0.7%) samples tested positive for SARS-CoV-2, while 69 samples were negative for fungi. In phase 4, 1/69 (1.4%) tested positive for bacteria, while no fungus or SARS-CoV-2 were detected. After the coating was applied, the bacterial load was reduced by 87% in phase 2 (RR = 0.132; 95% CI: 0.108-0.162); 99% in phase 3 (RR = 0.006; 95% CI: 0.003-0.015); and 100% in phase 4 (RR = 0.001; 95% CI: 0.000-0.009). These data indicate that the usnic-acid-containing coating was effective in eliminating bacterial, fungal, and SARS-CoV-2 contamination on surfaces in hospitals.Our findings support the benefit ofan usnic-acid-containing coating in reducing the microbial load on healthcare surfaces.

Antimicrobial Effectiveness of an Usnic-Acid-Containing Self-Decontaminating Coating on Underground Metro Surfaces in Athens.

(1) Background: Surfaces have been implicated in the transmission of infections. We aimed to assess how effective an usnic-acid-containing self-decontaminating coating was on the surfaces of the Athens underground metro. (2) Methods: Two samples were collected from each of 60 surfaces of a station and a wagon before the application of the coating and 9 and 20 days after, and they were tested for bacteria, fungi, and SARS-CoV-2 using conventional microbiological and molecular methods. Bacteria and fungi growth were expressed in colony forming units (CFUs)/102cm2. (3) Results: Before the application of the coating, 50% of the samples tested positive for the targeted microbes: 91.7% for bacteria, 18.3% for fungi, and 8.3% for SARS-CoV-2. After nine days, 3.3% of the samples tested positive for bacteria and 6.6% after 20 days. The average amount of bacteria before the coating was applied was 8.5 CFU/102cm2 compared to 0 and 0 CFU/102cm2 after application (100% and 95% reduction); all samples collected after the application were negative for SARS-CoV-2 and fungi (100% reduction). (4) Conclusion: An usnic-acid-containing self-decontaminating coating was highly effective in eliminating bacterial, fungal, and SARS-CoV-2 contamination of surfaces in the underground metro.

Spatiotemporal Distribution and Genetic Characterization of Measles Strains Circulating in Greece during the 2017-2018 Outbreak.

Between May 2017 and November 2018, Greece has experienced a severe measles outbreak with a total of 3258 cases reported, after reaching its goal of eliminating measles since 2014-2015. In this study, we aimed to investigate the origin and the dispersal patterns of the measles strains that circulated in Greece during this outbreak and to identify possible transmission patterns of measles virus (MeV) in the country. Of the 832 measles suspect cases referred to the National Measles and Rubella Reference Laboratory for MeV RNA detection, 131 randomly selected positive samples, representative of the temporal and spatial distribution of the laboratory-confirmed measles cases in Greece, were processed for genotypic identification by an RT-PCR amplification of a 598 bp fragment containing the 450 bp hypervariable region of the measles virus N gene. Phylogenetic analysis was carried out by the approximate maximum likelihood method (ML) under the generalized time-reversible (GTR + cat) model. All samples analyzed were found to belong to genotype B3. Comparative analysis with other European and reference measles strains revealed three separate major clusters and other multiple viruses circulating simultaneously in Greece. They were all isolated from three main community groups, Greek-Roma children, non-minority Greek nationals and immigrants/refugees, a finding that is in accordance with what was also observed in the last two measles outbreaks in 2005-2006 and 2010-2011. Notably, for one of the three clusters, no similarity was detected with previously reported prototype strains. Our results indicate the need for a more intensive vaccination program against measles amongst minority populations and in refugee hot-spots as well as the importance of molecular surveillance as a tool for monitoring measles outbreaks.

Human Herpesvirus 7-Related Acute Encephalopathy with Biphasic Seizures and Late Reduced Diffusion.

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is a recently described entity so far exclusively in East Asian children. AESD diagnosis is based on clinicoradiologic criteria, often without pleocytic CSF and characterized by hyperglycemia and transaminasemia. Here, we present the first case of human herpesvirus 7-related AESD in an immunocompetent child >2 years old and of Caucasian origin.

Cocirculation of genotypes D4 and D6 in Greece during the 2005 to 2006 measles epidemic.

One of World Health Organization's proposed methods for the establishment of measles surveillance worldwide, to achieve the elimination of measles virus by 2010, is the genetic characterization of measles wild-type virus strains. In this study, 34 measles virus strains, isolated from clinical samples during the 2005 to 2006 measles outbreak in Greece, were genotyped and studied in terms of nucleotide variation and phylogeny. Interestingly, the cocirculation of 2 different genotypes, namely, D6 and D4, was revealed. In fact, the D4 genotype has never been previously reported in Greece. Finally, although the D4 Greek strains possessed identical nucleotide sequences, the D6 isolates segregated into 3 distinct subgroups, 2 of which differed genetically and phenotypically from all GenBank deposited measles sequences. It is, thus, important to continue the epidemiologic surveillance of measles in Greece to aid future studies of measles transmission, monitor the effectiveness of measles immunization, and eventually document the elimination of the virus in our country.

Laboratory investigation and phylogenetic analysis of enteroviruses involved in an aseptic meningitis outbreak in Greece during the summer of 2007.

BACKGROUND: Aseptic meningitis is the most commonly observed CNS infection and is mainly attributed to Non-Polio Enteroviruses (EV). OBJECTIVE: Identification and genetic analysis of the EV involved in the recent aseptic meningitis outbreak which occurred in Greece, during the summer of 2007. STUDY DESIGN: In total, 213 CSF and faecal samples were examined for EV presence by culture, while enteroviral RNA detection was performed by nucleic acid sequence-based amplification assay (NASBA). EV strains were typed by seroneutralization, as well as nested RT-PCR followed by VP1-2A gene partial sequencing. Phylogenetic analysis was carried out for the identification of the genetic relatedness among the isolated EV strains. RESULTS: EV detection rate in CSF and faecal samples was 43.9% and 70.8%, respectively. EV serotyping and VP1 region analysis revealed the predominance of echovirus 4 (ECV4) serotype and the circulation of ECV6, 9, 14, 25, Coxsackie A6, A15, A24 and Coxsackie B1 serotypes. All ECV4 isolates presented a 98.7% similarity in nucleotide sequence, with a Spanish ECV4 strain, isolated during a meningitis outbreak in 2006. CONCLUSIONS: It is the first time that ECV4 is associated with an aseptic meningitis outbreak in Greece, during which 9 different EV serotypes were co-circulating. All Greek ECV4 isolates were closely related to the Spanish ECV4 strain. Genetic analysis of the VP1 gene can significantly contribute to the revelation of the endemic EV strains circulation pattern and their phylogenetic relationship with enteroviruses involved in epidemics of distant geographical areas at different time periods.