S. De Grazia

Viral gastroenteritis in children hospitalised in Sicily, Italy.

The aim of the present study was to describe the epidemiologic and clinical characteristics of acute viral gastroenteritis in hospitalised Italian children. A total of 215 stool specimens were collected from January to December 2003 from patients hospitalised in Palermo for acute diarrhoea. Samples were tested for group A rotavirus, astrovirus, adenovirus, norovirus, enteropathogenic bacteria, and parasites. Rotaviruses, mostly belonging to types G1–G4, were detected in 25.1% of samples, astrovirus in 7%, adenovirus in 6%, norovirus in 18.6%, and bacterial agents in 17.2%. No parasitic infections were diagnosed. Mixed infections represented 9.8% of all cases. The mean and median ages of children with rotavirus gastroenteritis were lower than those of children with other viruses (p=0.029), with the highest median ages being found in astrovirus-infected patients. Vomiting and dehydration were more frequent among patients with viral infection (p<0.01), and the severity score was significantly higher for children infected with astrovirus or group A rotavirus (p=0.008). Rotavirus was the leading cause of prolonged hospitalisation (p=0.005). In conclusion, viruses were confirmed in Italy as the most common cause of severe enteric illness in childhood, with rotavirus types G1–G4, which correspond to those included in the rotavirus vaccines being developed, playing the main role. Routine testing should be introduced for noroviruses, since they seem to represent an important cause of sporadic paediatric gastroenteritis.

Genetic Variability among Serotype G4 Italian Human Rotaviruses

ABSTRACT A total of 254 serotype GH rotavirus strains were detected in Palermo, Italy, from 1985 to 2003. Out of 38 serotype G4 strains selected for genetic analysis, 14 were recognized by genotyping as type G9. Strains confirmed to belong to the G4 type showed temporal patterns of genetic evolution in their VP7 and VP4 gene sequences, and the latest Italian G4 strains were distantly related to the reference vaccinal ST3 strain.

Genetic heterogeneity of porcine enteric caliciviruses identified from diarrhoeic piglets

Enteric caliciviruses (noroviruses and sapoviruses) are responsible for the majority of non-bacterial gastroenteritis in humans of all age groups. Analysis of the polymerase and capsid genes has provided evidence for a huge genetic diversity, but the understanding of their ecology is limited. In this study, we investigated the presence of porcine enteric caliciviruses in the faeces of piglets with diarrhoea. A total of 209 samples from 118 herds were analyszd and calicivirus RNA was detected by RT-PCR in 68 sample (32.5%) and in 46 herds (38.9%), alone or in mixed infection with group A and C rotaviruses. Sequence and phylogenetic analysis of the calicivirus-positive samples characterized the majority as genogroup III (GGIII) sapoviruses. Unclassified caliciviruses, distantly related to the representatives of the other sapovirus genogroups, were identified in five herds, while one outbreak was associated with a porcine sapovirus related genetically to human GGII and GGIV sapovirus strains. By converse, norovirus strains were not detected. Altogether, these data suggest the epidemiological relevance of porcine enteric caliciviruses and suggest a role in the etiology of piglets diarrhoea.

Evidence for Recombination between Pandemic GII.4 Norovirus Strains New Orleans 2009 and Sydney 2012

ABSTRACT During 2012, a novel pandemic GII.4 norovirus variant, Sydney 2012, emerged worldwide. A signature of the variant was a GII.Pe ORF1, in association with GII.4 Apeldoorn 2008-like ORF2-ORF3 genes. We report the detection of recombinant GII.4 Sydney 2012 strains, possessing the ORF1 gene of the former pandemic variant New Orleans 2009.

A feline rotavirus G3P[9] carries traces of multiple reassortment events and resembles rare human G3P[9] rotaviruses

The full-length genome sequence of a feline G3P[9] rotavirus (RV) strain, BA222, identified from the intestinal content of an adult cat, was determined. Strain BA222 possessed a G3-P[9]-I2-R2-C2-M2-A3-N1-T3-E2-H3 genomic constellation, differing substantially from other feline RVs. Phylogenetic analyses of each genome segment revealed common origins with selected animal and zoonotic human RVs, notably with rare multi-reassortant human G3P[9] RVs (Ita/PAI58/96 and Ita/PAH136/96). Altogether, the findings suggest that feline RVs are genetically diverse and that human RVs may occasionally originate either directly or indirectly (via reassortment) from feline RVs.

Molecular characterization of the genotype G9 human rotavirus strains recovered in Palermo, Italy, during the winter of 1999-2000

Among the known human rotavirus serotypes, types G1-G4 are ubiquitous and account for >80% of global human rotavirus strains. Since 1994 an increase in reports of G9 serotype isolates has been observed in both developed and developing countries. In the winter season of 1999-2000 we detected the appearance of G9 rotavirus in Palermo, Italy, accounting for 19% of all rotaviruses circulating in our geographical area. Some of these Italian G9 isolates have been submitted to partial sequencing of their VP7 gene. All of them showed complete nucleotide identity suggesting a clonal origin. The Italian VP7 sequences were found to be very closely related to that of other G9 strains recently isolated in Europe, America, Africa and Asia. Our results confirm that G9 strains circulating worldwide since 1994 are closely related genetically in their VP7 genes.

Surveillance of human astrovirus circulation in Italy 2002-2005: emergence of lineage 2c strains

By screening faecal samples collected over four consecutive years (2002-2005) from hospitalized children with diarrhoea in Palermo, Italy, astroviruses (HAstVs) were detected in 3.95% of the patients. The predominant type circulating was HAstV-1 but, in 2002, only HAstV-2 and -4 were identified. Interestingly, the HAstVs-2 detected appeared to be consistently different in 5′ end of their open reading frame 2 from the previously described subtypes. These novel type 2 strains were included in a new 2c lineage based on the phylogenetic analysis and the presence of nine peculiar substitutions.

Diversity of human rotaviruses detected in Sicily, Italy, over a 5-year period (2001-2005)

SummaryRotavirus infection was detected in 39.9% of 1030 children hospitalized with gastroenteritis in Palermo, Italy, in the period 2001–2005. Rotavirus strains belonging to G1, G4 and G9 types were continually detected, with G1 being the most common type in 2001, 2002 and 2004. A G4 epidemic occurred in 2003, while G9 was predominant in 2005. G2 strains displayed a low prevalence, except in 2003. G3 rotaviruses accounted for 2.7–17% of the gastroenteritis episodes in 2002–2005. The P-type of a subset of 166 strains confirmed the circulation of the usual G/P combinations, but single G1P[6], G9P[9] and G6P[9] strains were also found.

Genetic Heterogeneity and Recombination in Human Type 2 Astroviruses

ABSTRACT Novel lineages of human astrovirus (HAstV) types 2, 2c, and 2d have been identified. Upon sequencing of the 3′ end of the genome, the type 2c and 2d HAstVs were found to be open reading frame 1b (ORF1b)-ORF2 recombinant, with ORF1b being derived from type 3 and type 1 HAstVs, respectively. An ORF2 interlineage recombinant strain, 2c/2b, was also identified.

Human cytomegalovirus glycoprotein B genotypes in immunocompetent, immunocompromised, and congenitally infected Italian populations

Summary. Human cytomegalovirus (HCMV) strains, obtained from immunocompetent and immunocompromised Italian hosts, were typed with glycoprotein B (gB) gene restriction analysis. A predominant circulation of HCMV strains with gB type 2 and 3 was detected in both the immunocompetent host with a primary HCMV infection and the immunocompromised host with or without HCMV disease. No association between gB types and subjects with different risks of developing HCMV disease was found. All four gB genotypes were capable of causing congenital infection in Italian babies, with gB type 1 accounting for 50% of the strains examined in symptomatic infants and a remarkable incidence of gB type 4 viruses.