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Rotavirus group A (RVA) is characterized by molecular and epidemiological diversity. To date, 42 G and 58 P RVA genotypes have been identified, some of which, like P[14], have a zoonotic origin. In this study, we describe the epidemiology of unusual RVA genotypes and the molecular characteristics of P[14] strains. Fecal samples from children ≤ 16 years of age with acute gastroenteritis (AGE) who were hospitalized during 2007–2021 in Greece were tested for RVA by immunochromatography. Positive RVA samples were G and P genotyped, and part of the VP7 and VP4 genes were sequenced by the Sanger method. Epidemiological data were also recorded. Phylogenetic analysis of P[14] was performed using MEGA 11 software. Sixty-two (1.4%) out of 4427 children with RVA AGE were infected with an unusual G (G6/G8/G10) or P (P[6]/P[9]/P[10]/P[11]/P[14]) genotype. Their median (IQR) age was 18.7 (37.3) months, and 67.7% (42/62) were males. None of the children were vaccinated against RVA. P[9] (28/62; 45.2%) was the most common unusual genotype, followed by P[14] (12/62; 19.4%). In the last two years, during the period of the COVID-19 pandemic, an emergence of P[14] was observed (5/12, 41.6%) after an 8-year absence. The highest prevalence of P[14] infection was seen in the spring (91.7%). The combinations G8P[14] (41.7%), G6P[14] (41.7%), and G4P[14] (16.6%) were also detected. Phylogenetic analysis showed a potential evolutionary relationship of three human RVA P[14] strains to a fox strain from Croatia. These findings suggest a possible zoonotic origin of P[14] and interspecies transmission between nondomestic animals and humans, which may lead to new RVA genotypes with unknown severity.

Cellular immunity after SARS-CoV-2 infection or immunization may be important for long-lasting protection against severe COVID-19 disease. We investigated cellular immune responses after SARS-CoV-2 infection and/or vaccination with an interferon (IFN)-γ release assay (QuantiFERON, QFN). In parallel, we measured SARS-CoV-2 anti-Nucleocapsid (Abs-N), anti-Spike (Abs-S) and Neutralizing (NAbs) antibodies against SARS-CoV-2 wild type and Omicron variant. We recruited 41 participants: unvaccinated children and adults and vaccinated uninfected or vaccinated convalescent adults. All vaccinated adults had received three doses of the BNT162b2 COVID-19 vaccine at 6.2–10.9 months prior to their inclusion to the study. All the unvaccinated participants were tested negative with QFN. Regarding the vaccinated population, 50% (8/16) of the vaccinated uninfected adults and 57.1% (8/14) of the vaccinated convalescent adults were tested positive. Among the QFN positive individuals, a reactive response to antigen (Ag) 1 (CD4+ epitopes) and to Ag2 (CD4+ and CD8+ epitopes), was detected in 68.8% (11/16) and 87.5% (14/16) respectively, while 56.3% (9/16) had a reactive response to both antigens. Additionally, Ag1 IFN-γ values correlated with Abs-S (P P = 0.039) levels, but not with NAbs against Omicron variant (P = 0.09) and Ag2 IFN-γ values correlated only with Abs-S levels (P = 0.009). The SARS-CoV-2 QFN assay did not detect T cellular responses in unvaccinated individuals and in a significant number of vaccinated individuals. Further comparative studies with different immunology assays are required to elucidate whether this is the result of waning immunity or low sensitivity of the assay.

Rotavirus A (RVA) is characterized by molecular and epidemiological diversity. To date, 42G and 58P RVA genotypes have been identified, some of which have zoonotic origin, like P[14]. This study aims at the epidemiological and molecular characterization of human P[14] RVA. Fecal samples from children ≤ 16 years with acute gastroenteritis (AGE), hospitalized during 01/2007-12/2021, were tested for RVA by chromatographic immunoassay. Demographic, clinical and laboratory data were recorded. Positive RVA samples were G and P typed performing Sanger sequencing. Phylogenetic analysis of P[14] was performed using the Mega X software. Sixty (1.36%) out of 4427 children with RVA AGE, were infected with an unusual G (G6/G8/G10) or P (P[6]/P[9]/P[10]/P[11]/P[14]) genotype. P[9] (27/60; 45%) was the most common unusual genotype followed by P[14] (11/60; 18.3%). Median age of children with P[14] was 37.8 months (IQR:17.6–77.1), 6/11 were males and 4/11 resided to rural areas. Their symptoms were diarrhea (9/11; 81.8%), vomiting (7/11; 63.6%), fever (7/11; 63.6%) and moderate dehydration (6/11; 54.5%). All children were unvaccinated for RVA. Seasonal peak of P[14] was during spring (91%). The combinations G8P[14] (45.5%), G6P[14] (36.4%) and G4P[14] (18.1%) were detected. Phylogenetic analysis showed potential evolutionary relationship of three human RVA P[14] with a fox strain from Croatia. These findings enhance the potential zoonotic origin of P[14] and the interspecies transmission between nondomestic animals and humans, which may lead to new RVA genotypes with unknown severity.