The emergence, impact, and evolution of human metapneumovirus variants from 2014 to 2021 in Spain.

Background: Human metapneumovirus (HMPV) is an important aetiologic agent of respiratory tract infection (RTI). This study aimed to describe the prevalence, genetic diversity, and evolutionary dynamics of HMPV.

Methods: Laboratory-confirmed HMPV were characterised based on partial-coding G gene sequences with MEGA.

The frequency of defective genomes in Omicron differs from that of the Alpha, Beta and Delta variants.

The SARS-CoV-2 Omicron variant emerged showing higher transmissibility and possibly higher resistance to current COVID-19 vaccines than other variants dominating the global pandemic. In March 2020 we performed a study in clinical samples, where we found that a portion of genomes in the SARS-CoV-2 viral population accumulated deletions immediately before the S1/S2 cleavage site (furin-like cleavage site, PRRAR/S) of the spike gene, generating a frameshift and appearance of a premature stop codon. The main aim of this study was to determine the frequency of defective deletions in prevalent variants from the first to sixth pandemic waves in our setting and discuss whether the differences observed might support epidemiological proposals.

Emergence of Delta and Omicron variants carrying resistance-associated mutations in immunocompromised patients undergoing sotrovimab treatment with long-term viral excretion.

Objectives: To monitor the early emergence of genetic mutations related to reduced susceptibility to monoclonal anti-body (mAb)-based treatment in immunocompromised patients with long-term viral excretion using whole-genome sequencing at a tertiary university hospital in Barcelona, Spain.

Methods: Serial severe acute respiratory syndrome coronavirus 2-positive samples (mid-December 2021-mid-March 2022) from eight immunosuppressed, fully vaccinated patients (for solid-organ transplantation or haematologic malignancies) with long-term viral excretion despite undergoing mAb therapy (sotrovimab) for coronavirus disease 2019 were selected. Whole-genome sequencing was performed following the ARTIC, version 4.

Enterovirus D68 in Hospitalized Children, Barcelona, Spain, 2014-2021.

To determine molecular epidemiology and clinical features of enterovirus D68 (EV-D68) infections, we reviewed EV-D68-associated respiratory cases at a hospital in Barcelona, Spain, during 2014-2021. Respiratory samples were collected from hospitalized patients or outpatients with symptoms of acute respiratory tract infection or suggestive of enterovirus infection. Enterovirus detection was performed by real-time multiplex reverse transcription PCR and characterization by phylogenetic analysis of the partial viral protein 1 coding region sequences.

Characteristics of 24 SARS-CoV-2-Sequenced Reinfection Cases in a Tertiary Hospital in Spain.

Background: Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the main concern is whether reinfections are possible, and which are the associated risk factors. This study aims to describe the clinical and molecular characteristics of 24 sequence-confirmed reinfection SARS-CoV-2 cases over 1 year in Barcelona (Catalonia, Spain).

Methods: Patients with > 45 days between two positive PCR tests regardless of symptoms and negative tests between episodes were initially considered as suspected reinfection cases from November 2020 to May 2021.

A year living with SARS-CoV-2: an epidemiological overview of viral lineage circulation by whole-genome sequencing in Barcelona city (Catalonia, Spain).

Herein, we describe the genetic diversity of circulating SARS-CoV-2 viruses by whole-genome sequencing (WGS) in Barcelona city (Catalonia, Spain) throughout the first four pandemic waves. From weeks 11/2020-24/2021, SARS-CoV-2-positive respiratory samples were randomly selected per clinical setting (80% from primary care or 20% from the hospital), age group, and week. WGS was performed following the ARTICv3 protocol on MiSeq or NextSeq2000 Illumina platforms.

Host-dependent editing of SARS-CoV-2 in COVID-19 patients.

A common trait among RNA viruses is their high capability to acquire genetic variability due to viral and host mechanisms. Next-generation sequencing (NGS) analysis enables the deep study of the viral quasispecies in samples from infected individuals. In this study, the viral quasispecies complexity and single nucleotide polymorphisms of the SARS-CoV-2 gene of coronavirus disease 2019 (COVID-19) patients with mild or severe disease were investigated using next-generation sequencing (Illumina platform).

Coordinated Response to Imported Vaccine-Derived Poliovirus Infection, Barcelona, Spain, 2019-2020.

In 2019, the Public Health Agency of Barcelona, Spain, was notified of a vaccine-derived poliovirus infection. The patient had an underlying common variable immunodeficiency and no signs of acute flaccid paralysis. We describe the ongoing coordinated response to contain the infection, which included compassionate-use treatment with pocapavir.

Insights into immune evasion of human metapneumovirus: novel 180- and 111-nucleotide duplications within viral G gene throughout 2014-2017 seasons in Barcelona, Spain.

Background: Human metapneumovirus (HMPV) is an important aetiologic agent of respiratory tract infection (RTI). This study aimed to describe its genetic diversity and clinical impact in patients attended at a tertiary university hospital in Barcelona from the 2014-2015 to the 2016-2017 seasons, focusing on the emerging duplications in G gene and their structural properties.

Methods: Laboratory-confirmed HMPV were characterised based on partial-coding F and G gene sequences with MEGA.

Naturally occurring SARS-CoV-2 gene deletions close to the spike S1/S2 cleavage site in the viral quasispecies of COVID19 patients.

The SARS-CoV-2 spike (S) protein, the viral mediator for binding and entry into the host cell, has sparked great interest as a target for vaccine development and treatments with neutralizing antibodies. Initial data suggest that the virus has low mutation rates, but its large genome could facilitate recombination, insertions, and deletions, as has been described in other coronaviruses. Here, we deep-sequenced the complete SARS-CoV-2 gene from 18 patients (10 with mild and 8 with severe COVID-19), and found that the virus accumulates deletions upstream and very close to the S1/S2 cleavage site (PRRAR/S), generating a frameshift with appearance of a stop codon.

The high genetic similarity between rhinoviruses and enteroviruses remains as a pitfall for molecular diagnostic tools: A three-year overview.

Background: Enteroviruses (EVs) and rhinoviruses (RVs) belong to the Enterovirus genus within the Picornaviridae family, and show genetic similarities. These viruses are related to mild diseases, but EVs infections can sometimes lead to more severe complications. Current diagnostic molecular techniques should discriminate between the four EV and the three RV species that infect humans.

Recombinant CV-A6 strains related to hand-foot-mouth disease and herpangina at primary care centers (Barcelona, Spain).

To describe the genetic diversity of enteroviruses (EV) causing hand, foot and mouth disease (HFMD) and herpangina, especially of coxsackievirus (CV)-A6, from patients attended at pediatric primary care centers during the 2017-2018 season. Phylogenetic analysis of partial VP1 region was performed for genetic characterization. The complete VP1 and 3Dpol proteins were sequenced for lineage determination and detection of recombination events.

Molecular influenza surveillance at a tertiary university hospital during four consecutive seasons (2012-2016) in Catalonia, Spain.

Background: Influenza viruses (FLUV) are continuously evolving, which explain the occurrence of seasonal influenza epidemics and the need to review the vaccine strain composition annually. The aim is to describe the genetic diversity and clinical outcomes of FLUV detected at a tertiary university hospital in Barcelona (Spain) during the 2012-2016 seasons.

Methods: The detection of FLUV from patients attended at the Emergency Department or admitted to the hospital was performed by either immunofluorescence or PCR-based assays.

Surveillance of enteroviruses from paediatric patients attended at a tertiary hospital in Catalonia from 2014 to 2017.

Background: Enterovirus (EV) infections are usually asymptomatic or mild, but symptomatic infections can evolve to severe complications. Outbreaks of EV-A71 and EV-D68 have been recently reported worldwide, sometimes related to severe clinical outcomes.

Objective: To describe EV genetic diversity and the clinical outcomes from paediatric patients attended at a tertiary university hospital in Barcelona (Catalonia, Spain) from 2014 to 2017.

Genetic diversity of rhinoviruses detected at a tertiary hospital in Catalonia (Spain) during the 2014-2017 seasons.

Aim: To describe the genetic diversity of rhinovirus (RV) from patients attended at a tertiary hospital in Barcelona (Spain) from October 2014 to May 2017.

Methods: RV detection was performed by real-time multiplex RT-PCR. A specific real-time quantitive retrotranscription PCR (qRT-PCR) was carried out to select those samples (Ct < 35) for molecular characterization based on partial VP4/2 protein.

Evaluation of Seegene Allplex Respiratory Panel 1 kit for the detection of influenza virus and human respiratory syncytial virus.

Background: Influenza (FLUV) and human respiratory syncytial (HRSV) viruses are etiological agents of respiratory infections that cause a significant morbidity and mortality worldwide. A rapid and accurate diagnosis of these respiratory viruses is essential for an appropriate patient management. Molecular tests are the best detection option due to their high sensitivity and specificity.

Novel human metapneumovirus with a 180-nucleotide duplication in the G gene.

Aim: To describe the circulation, genetic diversity and clinical features of human metapneumovirus (HMPV) in pediatric patients that attended the Hospital Universitari Vall d'Hebron, Spain from 2014 to 2016.

Materials & Methods: Partial G gene was sequenced from laboratory-confirmed HMPV respiratory specimens for subsequent phylogenetic analysis.

Results: A total of 121 different samples were HMPV laboratory-confirmed out of 6658 specimens received.

A molecular epidemiological study of human parainfluenza virus type 3 at a tertiary university hospital during 2013-2015 in Catalonia, Spain.

Human parainfluenza virus type 3 (HPIV-3) is one of the most common respiratory viruses particularly among young children and immunocompromised patients. The seasonality, prevalence and genetic diversity of HPIV-3 at a Spanish tertiary-hospital from 2013 to 2015 are reported. HPIV-3 infection was laboratory-confirmed in 102 patients (76%, under 5 years of age).

Molecular epidemiology and molecular characterization of respiratory syncytial viruses at a tertiary care university hospital in Catalonia (Spain) during the 2013-2014 season.

Background: Human respiratory syncytial virus (HRSV) is the main cause of lower respiratory tract infections among infants and young children.

Objectives: The molecular epidemiology and characterization of HRSV strains detected at a Spanish tertiary hospital during the 2013-2014 season is reported.

Study Design: Phylogenetic analysis and molecular characterization of HRSV laboratory-confirmed respiratory samples were performed, based on coding sequences of G and F proteins.

First Enterovirus D68 (EV-D68) cases detected in hospitalised patients in a tertiary care university hospital in Spain, October 2014.

Several outbreaks of Enterovirus 68 (EV-D68) have recently been reported in the USA and Canada, causing substantial hospitalisation of children with severe respiratory disease. The acute flaccid paralysis detected in the USA and Canada among children with EV-D68 infection has raised concerns about the aetiological role of this EV serotype in severe neurological disease. The circulation of EV-D68 in the general European population seems to be low, but European Centre for Disease Prevention and Control (ECDC) recommends being vigilant to new cases, particularly in severely ill hospitalised patients.

[Microbiological diagnosis of central nervous system infections].

The infections of the central nervous system are associated with high morbidity and mortality. Several agents including bacteria, viruses, fungi and protozoa can invade the CNS. They are different clinical presentations of these infections: meningitis, encephalitis, brain and epidural abscesses and cerebrospinal fluid shunt infections.