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Background: Avian influenza A(H5N1) viruses have caused sporadic infections in humans and thus they pose a significant global health threat. Among symptomatic patients the case fatality rate has been ca. 50%. H5N1 viruses exist in multiple clades and subclades and several candidate vaccines have been developed to prevent A(H5N1) infection as a principal measure for preventing the disease., Methods: Serum antibodies against various influenza A(H5N1) clade viruses were measured in adults by ELISA-based microneutralization and haemagglutination inhibition tests before and after vaccination with two different A(H5N1) vaccines in 2009 and 2011., Results: Two doses of AS03-adjuvanted A/Indonesia/5/2005 vaccine induced good homologous but poor heterologous neutralizing antibody responses against different clade viruses. However, non-adjuvanted A/Vietnam/1203/2004 booster vaccination in 2011 induced very strong and long-lasting homologous and heterologous antibody responses while homologous response remained weak in naïve subjects., Conclusions: Sequential vaccination with two different A(H5N1) pre-pandemic vaccines induced long-lasting high level cross-clade immunity against influenza A(H5N1) strains, thus supporting a prime-boost vaccination strategy in pandemic preparedness plans., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Picornaviruses (family Picornaviridae) are small, nonenveloped, positive-sense, single-stranded RNA viruses. The members of this family are currently classified into 47 genera and 110 species. Of picornaviruses, entero- and parechoviruses are associated with aseptic meningitis. They are transmitted via fecal-oral and respiratory routes, and occasionally, these viruses may cause a brief viremia and gain access to central nervous system (CNS). During the diagnostic screening of entero- and parechovirus types in Finland in year 2013-14, we detected a cluster of echovirus 4 (E4) infections in young adults and adolescents. As E4 is infrequently detected in Finland, we contacted several Northern and Central European laboratories that conduct routine surveillance for enteroviruses and, for those who have had E4 cases, we send a query for E4 sequences and data. Here we report CNS infections caused by E4 in Finland, Sweden, Norway, Denmark, Iceland and Germany in 2013 and 2014, and show that the E4 detected in these countries form a single lineage. In contrast, E4 strains circulating in these countries preceding the year 2013, and those circulating elsewhere in Europe during 2013-2014, formed several independent clusters., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Influenza A(H1N1)pdm09 viruses have been circulating throughout the world since the 2009 pandemic. A/California/07/2009 (H1N1) virus was included in seasonal influenza vaccines for seven years altogether, providing a great opportunity to analyse vaccine-induced immunity in relation to the postpandemic evolution of the A(H1N1)pdm09 virus. Serum antibodies against various epidemic strains of influenza A(H1N1)pdm09 viruses were measured among health care workers (HCWs) by haemagglutination inhibition and microneutralization tests before and after 2010 and 2012 seasonal influenza vaccinations. We detected high responses of vaccine-induced neutralizing antibodies to six distinct genetic groups. Our results indicate antigenic similarity between vaccine and circulating A(H1N1)pdm09 strains, and substantial vaccine-induced immunity against circulating epidemic viruses., (Copyright © 2019. Published by Elsevier Ltd.)

Enteroviruses (EV) can cause severe neurological and respiratory infections, and occasionally lead to devastating outbreaks as previously demonstrated with EV-A71 and EV-D68 in Europe. However, these infections are still often underdiagnosed and EV typing data is not currently collected at European level. In order to improve EV diagnostics, collate data on severe EV infections and monitor the circulation of EV types, we have established European non-polio enterovirus network (ENPEN). First task of this cross-border network has been to ensure prompt and adequate diagnosis of these infections in Europe, and hence we present recommendations for non-polio EV detection and typing based on the consensus view of this multidisciplinary team including experts from over 20 European countries. We recommend that respiratory and stool samples in addition to cerebrospinal fluid (CSF) and blood samples are submitted for EV testing from patients with suspected neurological infections. This is vital since viruses like EV-D68 are rarely detectable in CSF or stool samples. Furthermore, reverse transcriptase PCR (RT-PCR) targeting the 5'noncoding regions (5'NCR) should be used for diagnosis of EVs due to their sensitivity, specificity and short turnaround time. Sequencing of the VP1 capsid protein gene is recommended for EV typing; EV typing cannot be based on the 5'NCR sequences due to frequent recombination events and should not rely on virus isolation. Effective and standardized laboratory diagnostics and characterisation of circulating virus strains are the first step towards effective and continuous surveillance activities, which in turn will be used to provide better estimation on EV disease burden., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: There is accumulating evidence that human rhinovirus (HRV) causes acute lower respiratory tract infections (ALRTI). Recently, HRV-C was identified as a new species of HRV, but its spectrum of clinical disease is not well understood., Objectives: We investigated the molecular epidemiology, demographic and clinical characteristics of HRVs among hospitalized children with ALRIs., Study Design: One hundred and sixty-five nasopharangeal aspirates taken from children <5 years hospitalized with ALRTIs in Serdang Hospital, Malaysia, were subject to reverse transcriptase-PCR for HRV. Phylogenetic analysis on VP4/VP2 and 5'-NCR regions was used to further characterize HRV. Other respiratory viruses were also investigated using semi-nested multiplex RT-PCR assay. Clinical parameters were analyzed between HRV, RSV and IFV-A mono-infections and between HRV species., Results: HRV was detected in 54 (33%) patients for both single (36 samples) and multiple (18 samples) infections, 61.1% (22/36) represents HRV-A strains while the remaining 14 HRV-C. Strain P51 was the first reported representative of HRV98. The majority of the single HRV cases were in the second half of infancy; HRV-C occurred among older children compared with HRV-A. HRV children were admitted significantly earlier and less febrile than RSV and IFV-A infection. HRV-C infected children were more likely to have rhonchi and vomiting as compared to HRV-A. Pneumonia was the most common discharge diagnosis followed by bronchiolitis and post-viral wheeze in HRV patients., Conclusion: Our study showed high prevalence of HRVs and detection of HRV-C among hospitalized children with ALRTIs in Malaysia. Analysis of clinical parameters suggested specific features associated with HRVs infections and specific HRV groups., (Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.)

Echovirus 6 (E-6) (family Picornaviridae, genus Enterovirus) is one of the most commonly detected enteroviruses worldwide. The aim of this study was to determine molecular evolutionary and epidemiologic patterns of E-6. A complete genome of one E-6 strain and the partial VP1 coding regions of 169 strains were sequenced and analyzed along with sequences retrieved from the GenBank. The complete genome sequence analysis suggested complex recombination history for the Finnish E-6 strain. In VP1 region, the phylogenetic analysis suggested three major clusters that were further divided to several subclusters. The evolution of VP1 coding region was dominated by negative selection suggesting that the phylogeny of E-6 VP1 gene is predominantly a result of synonymous substitutions (i.e. neutral genetic drift). The partial VP1 sequence analysis suggested wide geographical distribution for some E-6 lineages. In Finland, multiple different E-6 lineages have circulated at the same time., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Five oral poliovirus vaccine (OPV) strains carrying an intertypic PV3/PV2 recombination in VP1 capsid protein were isolated during poliovirus surveillance. These five PV3 strains had altogether four diverse recombination crossover points near the 3' end of the VP1 coding region. The complete antigenic site IIIa was replaced by PV2-specific amino acids in four of the studied PV3 strains. Low overall number of nucleotide substitutions in VP1 indicated that the predicted replication time, "age", of the PV3 strains was short, 6 months or less. The nucleotide 472-T in the 5' non-coding region, associated to the attenuated phenotype of PV3/Sabin, was reverted to wild-type C in all studied PV3/PV2 recombinant strains. Three of the PV3 strains had at least a tripartite genome deduced from the partial 3D polymerase-coding region sequences. Our results suggest that there exists a PV3/PV2 recombination hot-spot site in the 3' partial region of the VP1 capsid protein and that the recombination may occur within weeks or a few months after the administration of OPV., (Copyright 2010 Elsevier B.V. All rights reserved.)

Echovirus 11 (E-11) has been one of the most frequently discovered human enterovirus (HEV) in Finland during the past few years. We have studied molecular epidemiological patterns of E-11 from 1993 to 2007 exploiting the 257-nucleotide region in the 5'-part of the VP1 used for genetic typing of HEV. Designated genogroup D strains had a striking prevalence among the Finnish strains, a finding in accordance with the recent data from other geographical regions. The subgroup D4, harboring the oldest strains, had become extinct in the beginning of the millennium and D5 strains had taken over. Similarly, a new subgroup of D5 had started to diverge from the main D5 in 2006. However, in addition to endemic D strains, few single strains clustered also to genogroups A and C suggesting importation from more distant locations. The relatively large amino acid sequence variability between and within the genogroups favored the idea of antigenic differences. Neutralization assays confirmed that antigenic differences existed, although all studied E-11 strains were neutralized with antisera against the prototype strain Gregory. Five of the six studied strains belonging to genogroup D were, unexpectedly, also neutralized with antisera against coxsackievirus A9 Griggs.