Re-emergence of enterovirus D68 in Europe after easing the COVID-19 lockdown, September 2021

We report a rapid increase in enterovirus D68 (EV-D68) infections, with 139 cases reported from eight European countries between 31 July and 14 October 2021. This upsurge is in line with the seasonality of EV-D68 and was presumably stimulated by the widespread reopening after COVID-19 lockdown. Most cases were identified in September, but more are to be expected in the coming months. Reinforcement of clinical awareness, diagnostic capacities and surveillance of EV-D68 is urgently needed in Europe

Enterovirus- en parechovirus-surveillance in Nederland, 2015-2021

Enteroviruses (EVs) and parechoviruses (PEVs) circulate worldwide and can cause a wide variety of symptoms. The clinical EV/PEV surveillance is primarily aimed at excluding/confirming poliovirus (PV) in fecal samples tested positive for EV, and secondary at monitoring non-polio enteroviruses (NPEVs) and PEVs in all EV- and PEV-positive samples. With the recent increase in severity of NPEVs and PEVs, monitoring of NPEV and PEV circulation has become more important in the clinic and public health setting. The aim of this study is to describe the epidemiological and virological characteristics of NPEV and PEV circulation and to investigate the adequacy of PVexclusion. The surveillance is a collaboration between RIVM and a national network of medical microbiological laboratories that perform EV/PEV diagnostics/typing (n=36). Data on EV/PEV diagnostics and typing from 2015-2021 have been analyzed and show the yearly and monthly/seasonal detectionand circulation of PV, NPEVs and PEVs and the different circulating types. The number of samples tested has increased over the years. An average of 28,740 (EV) and 18,718 (PEV) samples was tested per year. The percentage of positive samples fluctuated between 5-9% (EV) and between 1.5-3.5% (PEV). The SARS-CoV-2 pandemic and COVID-19 measures have led to a lower circulation of NPEVs and PEVs was observed, particularly in 2020. Most EV and PEV positive samples were mainly detected in the summer spurring on into autumn/early winter. However, in 2020 and 2021 the detection in the fall/early winter was higher than in the summer. The NPEV types CV-A6, CV-B5, E-6, E-11, E-25, and EV-D68, and PEV types PEV-A1 and PEV-A3 were frequently found in the study period. Based on the data analyzed, the percentage of EV-positive fecal samplesthat have been typed is about 60-70% and decreases over the years studied. However, the percentage of EV-positive fecal samples in which PV was excludedwas lower and is about 50-60%. This is because culture on PV-permissive cells (L20B cells) was performed only in a small part of those EV positive fecalsamples where no NPEV type could be identified. Typing of EV and PEV positive samples is essential to monitor the epidemiological and virological featuresof NPEV and PEV circulation and PV detection.These data, and if possible combined with clinical data, are needed for early detection and outbreak investigation of NPEVs and for the purpose of monitoringpotential public health threats

Enterovirus- en parechovirus-surveillance in Nederland, 2015-2021

Enteroviruses (EVs) and parechoviruses (PEVs) circulate worldwide and can cause a wide variety of symptoms. The clinical EV/PEV surveillance is primarily aimed at excluding/confirming poliovirus (PV) in fecal samples tested positive for EV, and secondary at monitoring non-polio enteroviruses (NPEVs) and PEVs in all EV- and PEV-positive samples. With the recent increase in severity of NPEVs and PEVs, monitoring of NPEV and PEV circulation has become more important in the clinic and public health setting. The aim of this study is to describe the epidemiological and virological characteristics of NPEV and PEV circulation and to investigate the adequacy of PV exclusion. The surveillance is a collaboration between RIVM and a national network of medical microbiological laboratories that perform EV/PEV diagnostics/typing (n=36). Data on EV/PEV diagnostics and typing from 2015-2021 have been analyzed and show the yearly and monthly/seasonal detection and circulation of PV, NPEVs and PEVs and the different circulating types. The number of samples tested has increased over the years. An average of 28,740 (EV) and 18,718 (PEV) samples was tested per year. The percentage of positive samples fluctuated between 5-9% (EV) and between 1.5-3.5% (PEV). The SARS-CoV-2 pandemic and COVID-19 measures have led to a lower circulation of NPEVs and PEVs was observed, particularly in 2020. Most EV and PEV positive samples were mainly detected in the summer spurring on into autumn/early winter. However, in 2020 and 2021 the detection in the fall/early winter was higher than in the summer. The NPEV types CV-A6, CV-B5, E-6, E-11, E-25, and EV-D68, and PEV types PEV-A1 and PEV-A3 were frequently found in the study period. Based on the data analyzed, the percentage of EV-positive fecal samples that have been typed is about 60-70% and decreases over the years studied. However, the percentage of EV-positive fecal samples in which PV was excluded was lower and is about 50-60%. This is because culture on PV-permissive cells (L20B cells) was performed only in a small part of those EV positive fecal samples where no NPEV type could be identified. Typing of EV and PEV positive samples is essential to monitor the epidemiological and virological features of NPEV and PEV circulation and PV detection. These data, and if possible combined with clinical data, are needed for early detection and outbreak investigation of NPEVs and for the purpose of monitoring potential public health threats

Epidemiology of acute flaccid myelitis in children in the Netherlands, 2014 to 2019.

BackgroundAcute flaccid myelitis (AFM) is a polio-like condition affecting mainly children and involving the central nervous system (CNS). AFM has been associated with different non-polio-enteroviruses (EVs), in particular EV-D68 and EV-A71. Reliable incidence rates in European countries are not available.AimTo report AFM incidence in children in the Netherlands and its occurrence relative to EV-D68 and EV-A71 detections.MethodsIn 10 Dutch hospitals, we reviewed electronic health records of patients diagnosed with a clinical syndrome including limb weakness and/or CNS infection and who were < 18 years old when symptoms started. After excluding those with a clear alternative diagnosis to AFM, those without weakness, and removing duplicate records, only patients diagnosed in January 2014-December 2019 were retained and further classified according to current diagnostic criteria. Incidence rates were based on definite and probable AFM cases. Cases' occurrences during the study period were co-examined with laboratory-surveillance detections of EV-D68 and EV-A71.ResultsAmong 143 patients included, eight were classified as definite and three as probable AFM. AFM mean incidence rate was 0.06/100,000 children/year (95% CI: -0.03 to 0.14). All patient samples were negative for EV-A71. Of respiratory samples in seven patients, five were EV-D68 positive. AFM cases clustered in periods with increased EV-D68 and EV-A71 detections.ConclusionsAFM is rare in children in the Netherlands. The temporal coincidence of EV-D68 circulation and AFM and the detection of this virus in several cases' samples support its association with AFM. Increased AFM awareness among clinicians, adequate diagnostics and case registration matter to monitor the incidence