Search

Rhinovirus is one of the most common respiratory viruses, causing both upper and lower respiratory tract infections. It affects mainly children and could cause prolonged infections, especially in immunocompromised patients. Here we report our data on a 15-month surveillance of Rhinovirus seasonality and circulation in Lombardy Region, Italy. All rhinovirus/enterovirus-positive samples were amplified with RT-PCR for the VP4-VP2 region to assign the correct genotype. The median age of RV/EV-positive patients is 9 years, with a range of 0–96. RV-A and RV-C were detected in the majority of cases, while RV-B accounted for less than 10% of cases. An enterovirus species was detected in 6.45% of the cases. A total of 7% of the patients included in this study had a prolonged infection with a median duration of 62 days. All these patients were immunocompromised and most of them were pediatric with an RV-A infection. Two outbreaks were identified, mainly in the neonatal intensive care unit (NICU) and Oncohematology Department, caused by RV A89 and C43, respectively. Nearly 4.5% of the patients were admitted to the ICU requiring mechanical ventilation; all of which had preexisting comorbidities. [ABSTRACT FROM AUTHOR]

During the early phase of the pandemic (20 February–4 April 2020), we have investigated the temporal and geographical evolution of the virus in Lombardy showing the circulation of at least seven lineages distributed differently in the Region. In the present study, the molecular epidemiology of SARS‐CoV‐2 was monitored in a period between two pandemic waves in order to track the circulation of new variants (April‐August 2020). A great majority of SARS‐CoV‐2 strains (70.8%) belonged to lineages B, B.1, B.1.1 and B.1.1.1, and five strains belonging to four lineages were already reported in Italy (B.1.1.148, B.1.1.162, B.1.1.71, and B.1.425). In addition, 21 SARS‐CoV‐2 strains belonged to six lineages not previously observed in Italy were detected. No variants of concern were observed. A total of 152/1274 (11.3%) amino acid changes were observed among spike gene sequences and only 26/152 (17.1%) occurred in the receptor‐binding domain region of the spike protein. Results of this study are indicative of ongoing transmission throughout the lockdown period, rather than re‐introduction of novel lineages past lockdown. The use of molecular epidemiology in Italy should be promoted in order to provide additional understanding of the transmission of the disease and to have major effect on controlling the spread of disease. [ABSTRACT FROM AUTHOR]

• Circulation of heterogeneous variants during the pandemic waves. • One hundred and forty-seven mutations emerged in 2 years. • Vaccination and competition among variants caused the rise and fall of the circulating variants. Since the beginning of the pandemic, SARS-CoV-2 has shown genetic variability. All the variants that have sustained pandemic waves have shown several mutations, especially in the Spike protein that could affect viral pathogenesis. A total of 15,729 respiratory samples, collected between December 2020 and August 2022, have been included in this study. We report the circulation of SARS-CoV-2 variants in the Lombardy region, Italy, in a 2-year study period. Alpha, Delta, and Omicron variants became predominant causing the majority of cases whereas Beta or Gamma variants mostly caused local outbreaks. Next-generation sequencing revealed several mutations and few deletions in all of the main variants. For example, 147 mutations were observed in the Spike protein of Omicron sublineages; 20% of these mutations occurred in the receptor-binding domain region. [ABSTRACT FROM AUTHOR]