Following a distinct summer heat wave, nine autochthonous cases of West Nile fever and West Nile neuroinvasive disease, including one fatality, were observed in Leipzig, Germany, in August and September 2020. Phylogenetic analysis demonstrated close relationships in viruses from humans, animals and mosquitos in eastern Germany, obtained during the preceding 2 years. The described large cluster of autochthonous West Nile virus infections in Germany indicates endemic seasonal circulation of lineage 2 viruses in the area.

A rare G8P[4] rotavirus, designated GER1H-09, was detected in a stool sample from an infant suffering from repeated episodes of emesis for 2 days without diarrhea. Sequencing of all genomic RNA segments was performed, and complete coding sequences were determined. The VP7 amino acid sequence revealed a close phylogenetic relationship to human G8P[6] and G8P[8] isolates from Slovenia and Africa. GER1H-09 shared typical amino acid residues within variable regions VR3 to VR7 with those strains, and their subclassification as lineage G8-II rotaviruses is proposed. The variability in VR3 was identified as the likely reason for the failure in genotyping G8-II rotaviruses by commonly used multiplex PCR. Furthermore, the sequences of associated structural and nonstructural proteins showed high amino acid identities to DS-1-like rotaviruses. The genotype composition of GER1H-09 (G8-P[4]-I2-R2-C2-M2-A2-N2-T2-E2-H2) suggests the occurrence of reassortment events between G8 genotypes and human DS-1-like G2P[4] rotaviruses.

Background: The currently used SARS-CoV-2 mRNA vaccines have proven to induce a strong and protective immune response. However, functional relevance of vaccine-generated antibodies and their temporal progression are still poorly understood. Thus, the central aim of this study is to gain a better understanding of systemic and mucosal humoral immune response after mRNA vaccination with BNT162b2. Methods: We compared antibody production against the S1 subunit and the RBD of the SARS-CoV-2 spike protein in sera of BNT162b2 vaccinees, heterologous ChAdOx1-S/BNT162b2 vaccinees and COVID-19 patients. We monitored the neutralizing humoral response against SARS-CoV-2 wildtype strain and three VOCs over a period of up to eight months after second and after a subsequent third vaccination. Results: In comparison to COVID-19 patients, vaccinees showed higher or similar amounts of S1- and RBD-binding antibodies but similar or lower virus neutralizing titers. Antibodies peaked two weeks after the second dose, followed by a decrease three and eight months later. Neutralizing antibodies (nAbs) poorly correlated with S1-IgG levels but strongly with RBD-IgGAM titers. After second vaccination we observed a reduced vaccine-induced neutralizing capacity against VOCs, especially against the Omicron variant. Compared to the nAb levels after the second vaccination, the neutralizing capacity against wildtype strain and VOCs was significantly enhanced after third vaccination. In saliva samples, relevant levels of RBD antibodies were detected in convalescent samples but not in vaccinees. Conclusions: Our data demonstrate that BNT162b2 vaccinated individuals generate relevant nAbs titers, which begin to decrease within three months after immunization and show lower neutralizing potential against VOCs as compared to the wildtype strain. Large proportion of vaccine-induced S1-IgG might be non-neutralizing whereas RBD-IgGAM appears to be a good surrogate marker to estimate nAb levels. A third vaccination increases the nAb response. Furthermore, the systemic vaccine does not seem to elicit readily detectable mucosal immunity.

Following the extensive non-pharmaceutical interventions (NPIs) and behavioral changes in the wake of the SARS-CoV-2 pandemic, an interseasonal rise in respiratory syncytial virus (RSV) cases was observed in Germany in 2021. The aim of this study was to characterize the local molecular epidemiology of RSV infections in comparison to the three pre-pandemic seasons. Additionally, clinical data were retrieved from patient charts to determine the clinical significance of RSV infections. RSV detections peaked in calendar week 40 of 2021, 18 weeks earlier than the usual peak observed in the three pre-pandemic seasons. Sequence analysis revealed a close phylogenetic relatedness regardless of the season of origin. A significantly higher amount of pediatric cases (88.9% of all cases, p < 0.001) was observed for season 2021/2022. For the pediatric cases, significant differences were observed for an increased number of siblings in the household (p = 0.004), a lower rate of fever (p = 0.007), and a reduced amount of co-infections (p = 0.001). Although the mean age of the adult patients was significantly younger (47.1 vs. 64.7, p < 0.001), high rates of comorbidities, lower respiratory tract infections and intensive care unit admissions prevailed. The NPIs in the wake of the SARS-CoV-2 pandemic had a tremendous impact on the epidemiologic characteristics and seasonality of RSV and warrant further epidemiologic studies of this important pathogen.

Childhood morbidity and mortality of diarrhoeal diseases are high, particularly in low-income countries and noroviruses and sapoviruses are among the most frequent causes worldwide. Their epidemiology and diversity remain not well studied in many African countries. To assess the positivity rate and the diversity of sapoviruses and noroviruses in Northwest Ethiopia, during November 2015 and April 2016, a total of 450 faecal samples were collected from outpatient children aged <5 years who presented with diarrhoea. Samples were screened for noroviruses and sapoviruses by real-time RT-PCR. Partial VP1 genes were sequenced, genotyped and phylogenetically analysed. Norovirus and sapovirus stool positivity rate was 13.3% and 10.0%, respectively. Noroviruses included GII.4 (35%), GII.6 (20%), GII.17 (13.3%), GII.10 (10%), GII.2 (6.7%), GII.16 (5%), GII.7 (3.3%), GII.9, GII.13, GII.20 and GI.3 (1.7% each) strains. For sapoviruses, GI.1, GII.1 (20.0% each), GII.6 (13.3%), GI.2 (8.9%), GII.2 (11.1%), GV.1 (8.9%), GIV.1 (6.7%), GI.3 and GII.4 (2.2% each) genotypes were detected. This study demonstrates a high genetic diversity of noroviruses and sapoviruses in Northwest Ethiopia. The positivity rate in stool samples from young children with diarrhoea was high for both caliciviruses. Continued monitoring is recommended to identify trends in genetic diversity and seasonal variations.