Intensified Circulation of Echovirus 11 after the COVID-19 Pandemic in Poland: Detection of a Highly Pathogenic Virus Variant.

After the first phase of the COVID-19 pandemic in Europe, a new highly pathogenic variant of echovirus 11 (E11) was detected. The aim of this study was to analyze the genetic diversity of Polish E11 environmental and clinical strains circulating between 2017 and 2023 as well as compare them with E11 strains isolated from severe neonatal sepsis cases reported in Europe between 2022 and 2023. Additionally, the study explores the effectiveness of environmental monitoring in tracking the spread of new variants. For this purpose, the complete sequences of the VP1 capsid protein gene were determined for 266 E11 strains isolated in Poland from 2017 to 2023, and phylogenetic analysis was performed. In the years 2017-2023, a significant increase in the detection of E11 strains was observed in both environmental and clinical samples in Poland. The Polish E11 strains represented three different genotypes, C3, D5 and E, and were characterized by a high diversity. In Poland, the intensive circulation of the new variant E11, responsible for severe neonatal infections with a high mortality in Europe, was detected in the years 2022-2023. This investigation demonstrates the important role of environmental surveillance in the tracking of enteroviruses circulation, especially in settings with limited clinical surveillance.

Investigation of airport sewage to detect importation of poliovirus, Poland, 2017 to 2020.

BackgroundPolioviruses are human pathogens which may easily be imported via travellers from endemic areas and countries where oral polio vaccine (OPV) is still routinely used to polio-free countries. Risk of reintroduction strictly depends on polio immunisation coverage. Sustaining a polio-free status requires strategies that allow rapid detection and control of potential poliovirus reintroductions.AimThe aim of this study was to apply environmental surveillance at an international airport in Poland to estimate the probability of poliovirus importation via air transport.MethodsBetween 2017 and 2020, we collected 142 sewage samples at Warsaw Airport. After sewage concentration, virus was isolated in susceptible cell cultures. Poliovirus isolates were characterised by intratypic differentiation and sequencing.ResultsSeven samples were positive for polioviruses. All isolates were characterised as Sabin-like polioviruses type 3 (SL-3). No wild or vaccine-derived polioviruses were found. The number of mutations accumulated in most isolates suggested a limited circulation in humans. Only one SL-3 isolate contained seven mutations, which is compatible with more than half a year of circulation.ConclusionSince OPV was withdrawn from the immunisation schedule in Poland in 2016, detection of SL-3 in airport sewage may indicate the events of importation from a region where OPV is still in use. Our study shows that environmental surveillance, including airport sewage investigation, has the capacity to detect emerging polioviruses and monitor potential exposure to poliovirus importation. Poliovirus detection in sewage samples indicates the need for sustaining a high level of polio immunisation coverage in the population.

Molecular diagnosis of COVID-19 ­ present experiences / Molekularna diagnostyka COVID-19 ­ dotychczasowe doswiadczenia.

Severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2), a new highly emerging and pathogenic for human RNA virus, is responsible for the present COVID-19 pandemic. Molecular diagnostic methods, including real-time reverse transcription-PCR (RT-PCR) assay are the recommended methods for the identification and laboratory confirmation of COVID-19 cases. RT-PCR allows for detection the RNA of the virus in clinical specimens from patients suspected of COVID-19 with high specificity and sensitivity. Testing is still crucial for rapid detection of infected persons, implementation of appropriate measures to suppress further virus transmission and mitigate its impact. In response to demand of a molecular diagnostic test for SARS-CoV-2, within a first few months ongoing pandemic many commercial kits has become available on the market. However, these tests have varied in number and type of molecular targets, time of reaction as well as quality. In this study we compared different commercial tests for the detection of SARS-CoV-2 in clinical samples sending to Laboratory of Department of Virology, NIPH-NIH.

Genetic characterization of enterovirus A71 isolates from severe neurological cases in Poland.

The aim of this study was to report a minor outbreak of enterovirus A71 (EV-A71) infection in Poland and characterize isolates from cases of severe neurological infection detected in 2013 and 2016. Phylogenetic analysis revealed that Polish strains belonged to the C genogroup: C1, C2, and C4. Severe neurological manifestations as encephalitis or acute flaccid paralysis (AFP), were associated with all detected subgenogroups. The C2 subgenogroup was associated with the outbreak in Gdansk, with serious cases of AFP, myelitis, cerebellitis, encephalitis, but also with mild, sporadic cases of aseptic meningitis, in other Polish cities. Data from the study established relationships of EV-A71 from Poland with previously characterized strains and confirmed the importance of high quality enterovirus surveillance with international reach.

Molecular Characterization of Enteroviruses Isolated from Acute Flaccid Paralysis Cases in Poland, 1999-2014.

Enteroviruses (EVs) are among viral pathogens that can cause acute flaccid paralysis (AFP). This study represents an overview of EVs isolated through AFP surveillance in Poland between 1999 and 2014. The presence of enteroviruses was studied in stool samples that were collected from 747 AFP cases and their asymptomatic contacts. Fifty five (6.12%) cases of AFP were associated with enterovirus isolation. Out of the 55 positive cases, 40 were associated with detection of enterovirus in patient, and 15 with detection of EV in healthy contact, without positive detection in paralytic patient. Polioviruses were isolated from 35 AFP cases. The results of this study showed that about 43.6% of positive AFP cases were found in association with the isolation of non-polio enteroviruses (NPEV). A total of 12 different types of the species B were detected (CVA9, CVB1, CVB3, CVB4, CVB5, E3, E4, E9, E11, E13, E30), and one additional isolate represented the species enterovirus A (EV71). Among the 12 serotypes of species B, CVB3 and CVB5 were more frequently detected than others, representing 40% of the characterized isolates, followed by CVB4 (16%), E4 (8%), and E11(8%). Phylogenetic analysis revealed that strains from Poland had the closest genetic relationship with isolates previously identified in Europe (France, Finland, Denmark, Moldova) but also in other parts of the world (Tunisia, China, USA), suggesting wide distribution of these lineages. The paper provides information about NPEV circulation in Poland in the past 16 years, about its association with the AFP and it indicates the need for monitoring NPEV circulation even after the eradication of poliomyelitis.

Genetic Characterization of Human Enteroviruses Associated with Hand, Foot and Mouth Diseases in Poland, 2013-2016.

The objective of the present study was to describe the molecular characteristics of enteroviruses associated with hand, food, and mouth disease (HFMD) in Poland. Clinical material from HFMD cases, that occurred during 2013-2016 were examined. It has been showed that coxsackievirus A6 (CVA6), CVA10 and CVA16 were circulating in the country. Phylogenetic analysis showed that Polish CVA6 strains were divided into two distinct clusters suggesting two independent introductions. This is the first report of CVA6 infections associated with HFMD in Poland. These results emphasize the need for continuous monitoring of HFMD and facilitation of the diagnosis using molecular approaches.

Molecular characterization of environmental and clinical echovirus 6 isolates from Poland, 2006-2014.

The aim of this study was to investigate the genetic variability of echovirus 6 (E6) isolates from environmental samples and clinical cases of aseptic meningitis from 2006 to 2014. The analysis of the VP1 region showed the extensive diversity (up to 18.8%) and revealed that E6 circulating in Poland belong to four groups. Environmental strains clustered in three groups excepting the 2012 outbreak group, which shows the sudden introduction of new epidemic variant with Asiatic origin. Data from the study established relationships of E6 from Poland with previously characterized strains and confirmed the importance of both clinical and environmental surveillance. J. Med. Virol. 89:936-940, 2017. © 2016 Wiley Periodicals, Inc.

Molecular characterization of echovirus 30 isolates from Poland, 1995-2015.

Echovirus 30 (E30) is one of the most frequently identified enterovirus and a major cause of meningitis in children and adults. To investigate the genetic variability and relationship of E30 isolated from specimens of aseptic meningitis cases that occurred in Poland over a period of 20 years, sequences of VP1 gene were determined and genetic analysis was performed. From 1995 to 2015, 124 E30 were isolated using RD cells, and 58 isolates were sequenced and characterized by phylogenetic analysis of partial VP1 region (793 nt). In general, nucleotide sequence divergence in pairwise comparisons among Polish E30 isolates ranged from 0.0 to 15.0 %. The phylogenetic analysis revealed that E30 circulating in Poland since 1995 belong to two unique groups: Group I, characterized by high divergence (up to 13.1 %), segregated in four subgroups, and showed strong temporal circulation of E30. Group II, detected in Poland in 2013-2014, was closely correlated with two meningitis outbreaks and formed a separate genetically homogeneous group. Phylogenetic analysis revealed that strains from Poland had the closest genetic relationship with not only the isolates previously identified in Europe (Belarus, France, Germany, Italy, Russia) but also those in other parts of the world (Australia, China). Sequences of outbreak isolates were grouped in group II together with those from Russia and China isolated during 2010-2013. The identification of five distinct viral lineages during 1995-2015 confirmed the high E30 genetic diversity which may be an essential precondition for the emergence of new strains responsible for further potential aseptic meningitis outbreaks.

Enteroviruses Associated with Aseptic Meningitis in Poland, 2011-2014.

A 4-year study (2011-2014) of patients with meningitis was performed. Out of the 686 cerebrospinal fluid samples, 465 (67.8%) were posi-tive for eneteroviruses using RT-PCR and out of 334 clinical samples, 216 (64.7%) were positive for enteroviruses using cell culture methods. The highest detection rate was observed in the summer and autumn. In total, 185 enteroviruses were identified by using neutralization test. Echovirus 6 and 30 were the most common (41.7% and 37.5% respectively). The highest frequency of neurological infections (32.7%) occurred in children aged 5-9 years, mostly males (63.9%).

Enteroviruses Associated with Aseptic Meningitis in Poland, 2011­2014.

A 4-year study (2011­2014) of patients with meningitis was performed. Out of the 686 cerebrospinal fluid samples, 465 (67.8%) were positive for eneteroviruses using RT-PCR and out of 334 clinical samples, 216 (64.7%) were positive for enteroviruses using cell culture methods. The highest detection rate was observed in the summer and autumn. In total, 185 enteroviruses were identified by using neutralization test. Echovirus 6 and 30 were the most common (41.7% and 37.5% respectively). The highest frequency of neurological infections (32.7%) occurred in children aged 5­9 years, mostly males (63.9%).

Species-Specific Identification of Human Adenoviruses in Sewage.

Human adenovirus (HAdV) diversity in sewage was assessed by species-specific molecular methods. Samples of raw sewage were collected in 14 sewage disposal systems from January to December 2011, in Poland. HAdVs were detected in 92.1% of the analysed sewage samples and was significantly higher at cities of over 100 000 inhabitants. HAdV DNA was detected in sewage during all seasons. The most abundant species identified were HAdV-F (average 89.6%) and -A (average 19.6%), which are associated with intestine infections. Adenoviruses from B species were not detected. The result of the present study demonstrate that human adenoviruses are consistently present in sewage in Poland, demonstrating the importance of an adequate treatment before the disposal in the environment. Multiple HAdV species identified in raw sewage provide new information about HAdV circulation in the Polish population.