The final stages of polio eradication are proving more difficult than the early phases, and the development of effective drugs and treatments is considered a priority; thus, the research is ongoing. A screening of our in-house chemical library against poliovirus Sabin strains led to the identification of compounds 5 and 6 as hits active at submicromolar concentrations. Derivatives of these compounds were synthesized as a preliminary structure-activity-relationship study. Among them, 7 and 11 were highly active against poliovirus Sabin 1-3. Compound 11 was also very potent against a large panel of wild and vaccine-derived polioviruses. Time-of-addition experiments suggest that 5 and 7 could be active at an early stage of viral replication, whereas 11 was active at same concentration at all stages of viral replication. A ligand-based approach was applied to find the common structural features shared by the new compounds and already-known poliovirus inhibitors.
Within the initiatives for poliomyelitis eradication by WHO, Italy activated an environmental surveillance (ES) in 2005. ES complements clinical Acute Flaccid Paralysis (AFP) surveillance for possible polio cases, detects poliovirus circulation in environmental sewage, and is used to monitor transmission in communities. In addition to polioviruses, the analyses comprised: (i) the monitoring of the presence of non-polio enteroviruses in sewage samples and (ii) the temporal and geographical distribution of the detected viruses. From 2009 to 2015, 2880 sewage samples were collected from eight cities participating in the surveillance. Overall, 1479 samples resulted positive for enteroviruses. No wild-type polioviruses were found, although four Sabin-like polioviruses were detected. The low degree of mutation found in the genomes of these four isolates suggests that these viruses have had a limited circulation in the population. All non-polio enteroviruses belonged to species B and the most frequent serotype was CV-B5, followed by CV-B4, E-11, E-6, E-7, CV-B3, and CV-B2. Variations in the frequency of different serotypes were also observed in different seasons and/or Italian areas. Environmental surveillance in Italy, as part of the 'WHO global polio eradication program', is a powerful tool to augment the polio surveillance and to investigate the silent circulation or the re-emergence of enteroviruses in the population.
Background: Group A rotaviruses (RVA) are the leading cause of acute gastroenteritis (AGE) in young (aged <5 years) children, causing similar to 250,000 deaths worldwide, mostly in developing countries. Differences on nucleotide sequences of VP7 (G-type) and VP4 (P-type) genes are the basis for the binary RVA nomenclature. Although at least 32 G-types and 47 P-types of rotavirus are presently known, most RVA infections in humans worldwide are related to five major G/P combinations: G1P[8], G2P[4], G3P[8], G4P[8], and G9P[8].Aim: To provide the hospitals of the Italian surveillance network with update information on RVA AGE.Methods: During RVA gastroenteritis surveillance in Italy in 2012-14, a total of 2341 RVA-positive faecal samples were collected from children hospitalized with AGE, and RVA strains were genotyped following standard EuroRotaNet protocols.Findings: Most strains analysed belonged to the five major human genotypes and 118 out of 2341 (5.0%) were reported to be hospital-acquired. Comparison of the distributions of the RVA genotypes circulating in the community or associated with nosocomial infections showed a different distribution of genotypes circulating inside the hospital wards, with respect to those observed in the community. G1P[8] and G9P[8] RVA strains were detected frequently, whereas G12P[8] caused a single large nosocomial outbreak.Conclusion: The information from this study will be useful to implement guidelines for preventing RVA AGE and optimizing the management of patients in hospital wards. (C) 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
Group A rotaviruses (RVA) are the leading cause of acute gastroenteritis (AGE) in young children worldwide. The RVA outer capsid layer is composed of the VP7 and VP4 proteins. The VP7 (G-type) and VP4 (P-type) genotypes are the basis for the binary RVA nomenclature. At least 27 G-types and 37 P-types of RVA are currently known, but most of human infections are related to the five major genotypes G1P[8], G2P[4], G3P[8], G4P[8], and G9P[8]. Every year G1P[8] strains cause approximately 50% of all symptomatic RVA infections reported in children in Italy. Fifteen G1P[8] RVA strains identified in different areas of Italy between 2010 and 2014 were selected. Strains were subjected to nucleotide sequencing of the VP7, VP4, VP6 and NSP4 genes to investigate their genetic variability with respect to geographic area and date of detection. Phylogenetic analyses showed that the 15 G1P[8] RVA strains belonged to two different lineages for both the VP7 and NSP4 genes, and showed some intra-lineage diversity in VP4 and VP6 genes. Similarities between strains correlated by either area or date of detection were also evaluated. The results obtained by phylogenetic analyses were confirmed analyzing the deduced amino acid sequences of the VP7, VP4, VP6 and NSP4 proteins of the G1P[8] RVA strains, detecting several substitutions in all proteins. The genetic variability observed between common G1P[8] RVAs highlights the constant evolution of the RVA genome through random point mutations (genetic drift) and intra-genotype reassortment (genetic shift). The evolution and diversity of the G1 RVA strains observed in this study can be related to the naturally acquired herd immunity, which represents the main mechanism of selective pressure in Italy, where mass anti-rotavirus vaccination was missing during the years of the study.
Since 2007, the Italian Rotavirus Surveillance Program (RotaNet-Italy) has monitored the diversity and distribution of genotypes identified in children hospitalized with rotavirus acute gastroenteritis.We report the genomic characterization of two rare human G8P[14] rotavirus strains, identified in two children hospitalized with acute gastroenteritis in the southern Italian region of Apulia during rotavirus strain surveillance in 2012.Both strains showed a G8-P[14]-I2-R2-C2-M2-A11-N2-T6-E2-H3 genomic constellation (DS-1-like genomic background). Phylogenetic analysis of each genome segment revealed a mixed configuration of genes of animal and zoonotic human origin, indicating that genetic reassortment events generated these unusual human strains. Eight out of 11 genes (VP1, VP2, VP3, VP6, VP7, NSP3, NSP4 and NSP5) of the Italian G8P[14] strains exhibited close identity with a Spanish sheep strain, whereas the remaining genes (VP4, NSP1 and NSP2) were more closely related to human strains. The amino acid sequences of the antigenic regions of outer capsid proteins VP4 and VP7 were compared with vaccine and field strains, showing high conservation between the amino acid sequences of Apulia G8P[14] strains and human and animal strains bearing G8 and/or P[14] proteins, and revealing many substitutions with respect to the RotaTeq™ and Rotarix™ vaccine strains. Conversely, the amino acid analysis of the four antigenic sites of VP6 revealed a high degree of conservation between the two Apulia strains and the human and animal strains analyzed.These results reinforce the potential role of interspecies transmission and reassortment in generating novel rotavirus strains that might not be fully contrasted by current vaccines.
Background: Vaccine-associated paralytic poliomyelitis (VAPP) and immunodeficient long-term polio excretors constitute a significant public health burden and are a major concern for the WHO global polio eradication endgame.Case presentation: Poliovirus type 3 characterized as Sabin-like was isolated from a 5-month-old Albanian child with X-linked agammaglobulinemia and VAPP after oral polio vaccine administration. Diagnostic workup and treatment were performed in Italy. Poliovirus replicated in the gut for 7 months. The 5' non coding region (NCR), VP1, VP3 capsid proteins and the 3D polymerase genomic regions of sequential isolates were sequenced. Increasing accumulation of nucleotide mutations in the VP1 region was detected over time, reaching 1.0 % of genome variation with respect to the Sabin reference strain, which is the threshold that defines a vaccine-derived poliovirus (VDPV). We identified mutations in the 5' NCR and VP3 regions that are associated with reversion to neurovirulence. Despite this, all isolates were characterized as Sabin-like. Several amino acid mutations were identified in the VP1 region, probably involved in growth adaptation and viral persistence in the human gut. Intertypic recombination with Sabin type 2 polio in the 3D polymerase region, possibly associated with increased virus transmissibility, was found in all isolates. Gamma-globulin replacement therapy led to viral clearance and neurological improvement, preventing the occurrence of persistent immunodeficiency-related VDPV.Conclusions: This is the first case of VAPP in an immunodeficient child detected in Albania through the Acute Flaccid Paralysis surveillance system and the first investigated case of vaccine associated poliomyelitis in Italy since the introduction of an all-Salk schedule in 2002. We discuss over the biological and clinical implications in the context of the Global Polio Eradication Program and emphasize on the importance of the Acute Flaccid Paralysis surveillance.
AIM Rotavirus is recognized as the main cause of acute gastroenteritis in children under 5 years old, representing a considerable public health problem with a great impact on social and public health costs in developed countries. This study aims to assess the frequency and the epidemiological aspect of the hospitalization associated with Rotavirus-gastroenteritis in Lombardy, Northern Italy, from 2005 to 2011. METHODS The Lombardy Hospital Discharge Database was inquired from the official data of the Italian Ministry of Health and investigated for acute gastroenteritis (ICD9-CM code for bacteria, parasitic, viral and undetermined etiologic diarrhea) in primary and secondary diagnosis in children ≤ 5 years, between 2005 and 2011. RESULTS Out of the 32 944 acute-gastroenteritis hospitalizations reported in Lombardy, the 50.8% was caused by Rotavirus infection; of these, the 65.5% were reported in primary diagnosis. The peak of Rotavirus-gastroenteritis hospitalization was observed in February-March in children < 2 years old, with a cumulative prevalence of 64.5%. Patients admitted to hospital with diarrhea of undetermined etiology (about 14% of overall acute-gastroenteritis) showed epidemiological characteristics similar to the Rotavirus-gastroenteritis, suggesting that the virus infection could also be involved in at least some of these. CONCLUSION Our data confirm that Rotavirus are the most important agents involving in acute gastroenteritis hospitalizations. The use of Hospital Discharge Database had proved to be a simple tool to estimate the burden and to describe the epidemiological characteristics of Rotavirus gastroenteritis and could be used as a surveillance activity before and after the introduction of mass vaccination at national and regional level in Italy.
ABSTRACT Although the molecular surveillance network RotaNet-Italy provides useful nationwide data on rotaviruses causing severe acute gastroenteritis in children in Italy, scarce information is available on rotavirus circulation in the general Italian population, including adults with mild or asymptomatic infection. We investigated the genotypes of rotaviruses present in urban wastewaters and compared them with those of viral strains from clinical pediatric cases. During 2010 and 2011, 285 sewage samples from 4 Italian cities were tested by reverse transcription-PCRs (RT-PCRs) specific for rotavirus VP7 and VP4 genes. Rotavirus was detected in 172 (60.4%) samples, 26 of which contained multiple rotavirus G (VP7 gene) genotypes, for a total of 198 G types. Thirty-two samples also contained multiple P (VP4 gene) genotypes, yielding 204 P types in 172 samples. Genotype G1 accounted for 65.6% of rotaviruses typed, followed by genotypes G2 (20.2%), G9 (7.6%), G4 (4.6%), G6 (1.0%), G3 (0.5%), and G26 (0.5%). VP4 genotype P[8] accounted for 75.0% of strains, genotype P[4] accounted for 23.0% of strains, and the uncommon genotypes P[6], P[9], P[14], and P[19] accounted for 2.0% of strains altogether. These rotavirus genotypes were also found in pediatric patients hospitalized in the same areas and years but in different proportions. Specifically, genotypes G2, G9, and P[4] were more prevalent in sewage samples than among samples from patients, which suggests either a larger circulation of the latter strains through the general population not requiring medical care or their greater survival in wastewaters. A high level of nucleotide identity in the G1, G2, and G6 VP7 sequences was observed between strains from the environment and those from patients.
Rotavirus gastroenteritis is associated mainly with the five genotypes G1,3,4,9P[8] and G2P[4] that are common worldwide, but emerging strains including G6, G8, and G12 are also reported sporadically. G12P[8] rotavirus was observed unexpectedly to spread in a limited area of Italy during the rotavirus surveillance season 2012–2013. All strains were genotyped for VP7 and VP4 and subjected to phylogenetic analysis. Amino acid sequences of antigenic regions were compared with vaccine and field strains. G12P[8] strains were detected in the stools of 52 of 69 (75%) children infected with rotavirus in the central Italian region of Umbria. All G12 strains belonged to lineage III, and presented the P[8] genotype. Sequence analysis showed close nucleotide identity of both VP4 and VP7 genes among Umbria G12P[8] strains. The VP7 gene was also similar to other G12 strains circulating in different years and countries, and the VP4 gene was closely related to other local and global P[8] strains possessing different G‐types. Overall findings suggest either the introduction and evolution of a G12 VP7 gene into the local Wa‐like rotavirus population or the spreading of a strain novel for the area. Comparison of the VP8* and VP7 antigenic regions showed high conservation between the amino acid sequences of Umbria G12P[8] strains, and revealed various substitutions in the VP8* antigenic regions between the Italian G12P[8] strains and RotaTeq™ and Rotarix™ vaccine strains. The sudden and unexpected emergence of G12P[8] rotavirus confirms that these strains have the potential to become a sixth common genotype across the world. J. Med. Virol. 87:1292–1302, 2015 . © 2015 Wiley Periodicals, Inc.
Group A rotaviruses (RVA) are the leading cause of acute gastroenteritis (AGE) in children worldwide and cause up to 455,000 deaths annually, mostly in developing countries. During 2013, 66 RVAs from children with AGE admitted to four Nigerian hospitals were investigated. The G3P[6], G1P[8] and G2P[4] genotypes predominated. The VP7 and/or VP4 genes of 18 G3P[6]/[8]/[4], six G2P[4], three G12P[8]/[4], and two G1P[8] RVA strains were sequenced. The G3P[6] strains belonged to lineage G3-III and were different from G3 strains widespread in Asia. Phylogenetic analysis revealed substantial sequence conservation, suggesting continuing evolution and genomic reassortment but no zoonotic RVA transmission from animals.
Abstract: Rotavirus strains with the uncommon genotype G10 have been detected sporadically in cases of acute gastroenteritis in humans and are thought to be transmitted zoonotically. During 2009, ten G10P[8] rotavirus strains were detected in the stools of children hospitalized with acute diarrhea in several pediatric hospitals in Italy. The phylogenetic analysis of the VP7 gene of the Italian G10P[8] strains analyzed revealed nucleotide identities ranging from 94% to 99%. Molecular characterization of the 11 genomic segments was performed for one of the G10 strains, which displayed a complete genomic constellation 1 for the non-G genes. The analysis of the deduced amino acid sequences of the G10 VP7 epitopes revealed low amino acid identity with common human strains of different G genotype and with the VP7 proteins included in both antirotavirus commercial vaccines (Rotarix and RotaTeq). Among the common G genotypes, the VP7 amino acid sequence of the G10 strains showed a high similarity with sequences from G9 strains. A hydrophobic cluster analysis (HCA) of the VP7 protein including amino acids from 20 to 298 was performed for the G10 Italian sequences in comparison with the major human RVA G genotypes. The HCA analysis confirmed the findings obtained previously by amino acid analysis of the VP7 epitopes, detecting a genotype-specific pattern of hydrophobicity in the hypervariable regions of the major outer capsid protein.
Rotavirus strains with the uncommon genotype G10 have been detected sporadically in cases of acute gastroenteritis in humans and are thought to be transmitted zoonotically. During 2009, 10 G10P[8] rotavirus strains were detected in the stools of children hospitalized with acute diarrhoea in several paediatric hospitals in Italy. The phylogenetic analysis of the VP7 gene of the Italian G10P[8] strains analysed revealed nucleotide identities ranging from 94 to 99 %. Molecular characterization of the 11 genomic segments was performed for one of the G10 strains, which displayed a complete genomic constellation 1 for the non-G genes. The analysis of the deduced amino acid sequences of the G10 VP7 epitopes revealed low amino acid identity with common human strains of different G genotype and with the VP7 proteins included in both anti-rotavirus commercial vaccines (Rotarix and RotaTeq). Amongst the common G genotypes, the VP7 amino acid sequence of the G10 strains showed a high similarity with sequences from G9 strains. A hydrophobic cluster analysis (HCA) of the VP7 protein including aa 20-298 was performed for the G10 Italian sequences in comparison with the major human group A rotavirus G genotypes. The HCA analysis confirmed the findings obtained previously by amino acid analysis of the VP7 epitopes, detecting a genotype-specific pattern of hydrophobicity in the hypervariable regions of the major outer capsid protein.
Group A rotaviruses (RVA) are the leading cause of acute gastroenteritis in young (<5 years of age) children, causing up to 450.000 deaths worldwide, mostly in developing countries. VP7 (G-type) and VP4 (P-type) genotypes are the basis for the binary RVA classification. Although at least 27 G-types and 37 P-types of rotavirus are presently known, most RVA infections in humans worldwide are associated with the five major G/P combinations G1P[8], G2P[4], G3P[8], G4P[8] and G9P[8]. During RVA gastroenteritis surveillance in Italy, a total of 1112 samples collected from children hospitalized with acute gastroenteritis in 2013 were RVA positive and were genotyped following standardized protocols from the EuroRotaNet. Most strains analyzed belonged to the five major human genotypes. Among these common strains, 22 G4P[8] RVA strains from different Italian regions were subjected to nucleotide sequencing of their VP4, VP6, VP7 and NSP4 genes to investigate their evolution. The phylogenetic analysis showed that the Italian strains belonged to lineage G4-I for VP7 and to lineage P[8]-III for VP4, in line with the modern G4P[8] RVA strains detected in children worldwide. The phylogenetic trees revealed high degrees of nucleotide identity between the RVA strains involved in this study and G4P[8] strains detected previously in Europe, Asia and Africa, but also demonstrated at least three separate evolution clusters within the same lineage. Based on the amino acid sequences deduced for their hypervariable regions, both the VP7 and VP8* proteins of the Italian G4P[8] RVA strains presented amino acid substitutions near known neutralizing epitopes.
Group A rotaviruses (RVA) are the leading cause of acute gastroenteritis in young children, causing up to 450,000 deaths worldwide, mostly in developing countries. Most of RVA human infections in developed countries are related to five major G/P combinations: G1P[8], G2P[4], G3P[8], G4P[8] and G9P[8]. During the surveillance activity of RotaNet-Italy, three uncommon G3P[6] RVA strains, designated as RVA/Human-wt/ITA/NA01/2009/G3P[6], RVA/Human-wt/ITA/NA06/2009/G3P[6], and RVA/Human-wt/ITA/NA19/2009/G3P[6], were identified in the stools of children with diarrhea hospitalized in Southern Italy in 2009. Samples NA01, NA06 and NA19 were characterized as genotype G3P[6]. To investigate the three strains further, partial sequencing of the eleven genomic segments was performed. RVA strains NA01, NA06 and NA19 were found to share the rare genotype constellation: G3-P[6]-I2-R2-C2-M2-A2-N2-T2-E2-H2, which had not been reported previously in continental Italy. The phylogenetic analysis of the eleven genomic segments showed no evidence of zoonosis or inter-species reassortment at the origin of the Italian G3P[6] strains, indicating that they possessed DS-1-like genomic constellations similar to those detected previously in human cases in Africa and Europe. The analysis of the hypervariable regions of VP7 and VP4 (VP8*) revealed high amino acid identity between the Italian G3P[6] RVA strains involved in this study.
This study evaluated the presence and seasonal distribution of polio and other enteroviruses in four wastewater treatment plants in three cities in Italy, using different treatment systems. Detection of enteroviruses was carried out by virus isolation in cell cultures after concentration of water samples collected at both inlet and outlet of the treatment plants, following the methods described in the WHO guidelines. Viral serotypes isolated before and after water treatment were compared. Forty-eight non-polio enteroviruses were isolated from 312 samples collected at the inlet of the four wastewater treatment plants, 35 of which were Coxsackievirus type B (72.9 %) and 13 Echovirus (27.1 %). After treatment, 2 CVB3, 1 CVB5, and 1 Echo 6 were isolated. CVB3 and Echo 6 serotypes were also detected in samples collected at the inlet of the TP, in the same month and year. The high rate of detection of infectious enteroviruses in inlet sewage samples (30.1 %) indicates wide diffusion of these viruses in the populations linked to the collectors. The incomplete removal of infectious viruses following sewage treatment highlights possible risks for public health relate to treated waters discharge into the environment.