From Alpha to Delta-Genetic Epidemiology of SARS-CoV-2 (hCoV-19) in Southern Poland

Neighbourhood watch: genomic epidemiology of SARS-CoV-2 variants circulating in a German federal state, Mecklenburg-Western Pomerania, in 2020-2022

ABSTRACTGlobal and even national genome surveillance approaches do not provide the resolution necessary for rapid and accurate direct response by local public health authorities. Hence, a regional network of microbiological laboratories in collaboration with the health departments of all districts of the German federal state of Mecklenburg-Western Pomerania (M-V) was formed to investigate the regional molecular epidemiology of circulating SARS-CoV-2 lineages between 11/2020 and 03/2022. More than 4750 samples from all M-V counties were sequenced using Illumina and Nanopore technologies. Overall, 3493 (73.5%) sequences fulfilled quality criteria for time-resolved and/or spatially-resolved maximum likelihood phylogenic analyses and k-mean/ median clustering (KMC). We identified 116 different Pangolin virus lineages that can be assigned to 16 Nextstrain clades. The ten most frequently detected virus lineages belonged to B.1.1.7, AY.122, AY.43, BA.1, B.1.617.2, BA.1.1, AY.9.2, AY.4, P.1 and AY.126. Time-resolved phylogenetic analyses showed the occurrence of virus clades as determined worldwide, but with a substantial delay of one to two months. Further spatio-temporal phylogenetic analyses revealed a regional outbreak of a Gamma variant limited to western M-V counties. Finally, KMC elucidated a successive introduction of the various virus lineages into M-V, possibly triggered by vacation periods with increased (inter-) national travel activities. The COVID-19 pandemic in M-V was shaped by a combination of several SARS-CoV-2 introductions, lockdown measures, restrictive quarantine of patients and the lineage specific replication rate. Complementing global and national surveillance, regional surveillance adds value by providing a higher level of surveillance resolution tailored to local health authorities.

Ensitrelvir is effective against SARS-CoV-2 3CL protease mutants circulating globally

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a public health concern worldwide. Ensitrelvir (S-217622) has been evaluated as an antiviral treatment for COVID-19, targeting SARS-CoV-2 3C-like protease (3CL^pro). Ensitrelvir has been reported to have comparable antiviral activity against some of the SARS-CoV-2 variants: alpha, beta, gamma, delta, and omicron (BA.1.18). In this paper, we describe that ensitrelvir is effective against newly emerging SARS-CoV-2 variants and globally prevalent 3CL^pro mutations. Ensitrelvir exhibited comparable antiviral activity against SARS-CoV-2 variants, including recently emerging ones: omicron (BA1.1, BA.2, BA.2.75, BA.4, BA.5, BQ.1.1, XBB.1, and XE), mu, lambda, and theta. Genetic surveillance of SARS-CoV-2 3CL^pro, the target of ensitrelvir, was conducted using a public database and identified 11 major 3CL^pro mutations circulating globally (G15S, T21I, T24I, K88R, L89F, K90R, P108S, P132H, A193V, H246Y, and A255V). The 3CL^pro mutation from proline to histidine at amino acid position 132 was especially identified in the omicron variant, with prevalence of 99.69%. Enzyme kinetic assay revealed that these 3CL^pro mutants have enzymatic activity comparable to that of the wild type (WT). Next, we assessed the inhibitory effect of ensitrelvir against mutated 3CL^pro, with it showing inhibitory effects similar to that against the WT. These in vitro data suggest that ensitrelvir will be effective against currently circulating SARS-CoV-2 variants, including omicron variants and those carrying 3CL^pro mutations, which emerging novel SARS-CoV-2 variants could carry.

In-depth genetic characterization of the SARS-CoV-2 pandemic in a two-year frame in North Macedonia using second and third generation sequencing technologies

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a persistent negative impact on both the public health and the global economy. To comprehend the origin, transmission routes and discover the mutations that alter the virus’s transmissibility and pathogenicity, full-length SARS-CoV-2 genomes have to be molecularly characterized. Focusing on a two-year time frame (2020-2021), we provide an in-depth virologic and epidemiological overview of the SARS-CoV-2 pandemic in the Republic of North Macedonia by assessing the frequency and distribution of the circulating SARS-CoV-2 variants. Using genetic characterization and phylogenetic analysis we shed light on the molecular evolution of the virus as well as test for a possible connection between specific SARS-CoV-2 haplotypes and the severity of the clinical symptoms. Our results show that one fifth (21.51%) of the tested respiratory samples for SARS-CoV-2 were positive. A noticeable trend in the incidence and severity of the COVID-19 infections was observed in the 60+ age group between males and females. Of the total number of positive cases, the highest incidence of SARS-CoV-2 was noticed in 60+ males (4,170.4/100,000), with a statistically significant (0,0001) difference between the two sexes. Additionally, a 1.8x increase in male mortality and consequentially significantly higher number of death cases was observed compared to females of the same age group (0.001). A total of 327 samples were sequenced in the period March 2020 - August 2021, showing the temporal distribution of SARS-CoV-2 variants circulating in North Macedonia. The phylogenetic analysis showed that most of the viral genomes were closely related and clustered in four distinctive lineages, B.1, B.1.1.7, B.1.351 and B.1.617.2. A statistically significant difference was observed in the 2C_1 haplotype (p=0.0013), where 10.5% of the patients were hospitalized due to severe clinical condition. By employing genetic sequencing, coupled with epidemiological investigations, we investigated viral distribution patterns, identified emerging variants and detected vaccine breakthrough infections. The present work is the first molecular study giving a comprehensive overview of the genetic landscape of circulating SARS-CoV-2 viruses in North Macedonia in a period of two years.

A Retrospective Population Study of 385 191 Positive Real-Time Reverse Transcription-Polymerase Chain Reaction Tests For SARS-CoV-2 from a Single Laboratory in Katowice, Poland from April 2020 to July 2022

BACKGROUND This retrospective population study identified 385 191 positive real-time reverse transcription-polymerase chain reaction (RT-PCR) tests for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from a single laboratory in Katowice, Poland, from April 2020 to July 2022. MATERIAL AND METHODS The material was nasopharyngeal, nasopharyngeal swab or bronchial lavage, and bronchoalveolar lavage (BAL) to confirm or exclude SARS-CoV-2 infection with the RT-PCR technique. Personal data are use according to the Provisions on the Protection of Personal Data by the Gyn-Centrum laboratory. RESULTS In 9 months of 2020, the number of SARS-CoV-2 results was 88 986; in 2021, it was 168 439, and in the first 7 months of 2022, it was 12 786. In 2020, the highest number of positive results was recorded in the third quarter (83 094 cases); 2021, in the 1st, 2nd, and 4th quarters (58 712; 37 720; and 71 753 cases, respectively), and in 2022, in the 1st quarter (127 613 cases) of the year. A positive result was observed more often in women and people aged 30-39, followed by those 40-49 years. Patients aged 10-19 years comprised the smallest population of SARS-CoV-2-positive cases. CONCLUSIONS In the Polish population studied, from April 2020 to July 2022, the detection rates of SARS-CoV-2 positivity were significantly higher for women than for men and in the 30-49 age group for both sexes. Also, the infection detection rate of 385 191 out of 1 332 659 patient samples, or 28.9%, supports that the Polish society adhered to public health recommendations for infection control during the COVID-19 pandemic.