Rotavirus Strain Diversity in the Centre Coast of Tunisia from 2000 through 2003

An epidemiological survey investigating rotavirus infection in children was undertaken in the coastal region of Tunisia from January 2000 through September 2003. A total of 309 fecal specimens were screened by enzyme-linked immunosorbent assay and latex agglutination assay for the presence of group A rotavirus antigen. The detection rate was 26.2%. Rotavirus outbreaks showed a temperature-dependant pattern (P= .026) but no significant association with rainfall. Rotavirus strains isolated were analyzed by RNA polyacrylamide gel electrophoresis and were characterized antigenically by monoclonal antibodies to the VP6 subgroup. Eight RNA electropherotypes were identified, with 3 long and 5 short different RNA profiles. Among VP6 typeable strains, all isolates with a long electrophoretic pattern carried the subgroup II specificity, whereas those with a short profile belonged to subgroup I. In total, 48 rotavirus-positive samples were analyzed for G and P typing by reverse-transcription polymerase chain reaction. A total of 8 different G and P combinations were found: G1P[8] (35.7%), G1P[6] (21.4%), G2P[4] (4.8%), G3P[4] (4.8%), G4P[6] (4.8%), G8P[8] (4.8%), G3P[8] (2.3%), and G4P[8] (2.3%). Mixed infections were detected in 19.1% of stool samples. The emergence in Tunisia of unconventional types, such as G8VP7 specificity, highlights the need for a continual survey of the uncommon strains in North Afric

Molecular analysis of adenovirus strains responsible for gastroenteritis in children, under five, in Tunisia

Purpose of work: Enteric Adenovirus (EAdV) is recognized as one of the most commonly identified agents responsible for severe acute gastroenteritis (AGEs) in the stools of infants.We sought to determine the rate of human adenovirus (HAdV) infections, and the genotypic characterization of circulating strains of HAdV in children under 5 years of age with AGEs in university and regional hospitals, located in the Center-East of Tunisia, from January 2014 to December 2016. Methods: A classic PCR was performed on 582 stool samples taken within 5 days of the onset of symptoms. Chosen positive samples were sequenced, and some of the results were confirmed by the Next Generation Sequencing technique (NGS). Partial nucleotide sequences of the Hexon gene obtained in this study were compared with the NCBI GenBank database using BLAST. Multiple sequence alignment and phylogenetic analysis were conducted using MEGA6 software. The phylogenetic tree was generated using the maximum-likelihood method and bootstrap analysis was performed with 1000 replications. Results: Out of 582 samples, 52 (8.93 %) cases were positive for HAdV, with a male predominance (57.4 %). Phylogenetic analyses showed that Tunisian HAdV strains clustered into five HAdV lineages corresponding to serotypes F41 (14/28), C2 (9/28), C5 (3/28), E4 (1/28), and A18 (1/28). HAdV was more frequent in children aged up to 12 months, as compared to the other age groups. The HAdV activity was noted in almost all the months of the year with a peak in autumn, in 2014 and 2015, and in winter in 2016. Conclusion: This study showed that infections with HAdV species were frequent in children suffering from AGE with the predominance of HAdV F41 and C2. This result underlines the importance of regular monitoring of circulating genotypes, and it could be useful for future epidemiological research

Feline Origin of Rotavirus Strain, Tunisia, 2008

In Tunisia in 2008, an unusual G6P[9] rotavirus, RVA/human-wt/TUN/17237/2008/G6P[9], rarely found in humans, was detected in a child. To determine the origin of this strain, we conducted phylogenetic analyses and found a unique genotype constellation resembling rotaviruses belonging to the feline BA222-like genotype constellation. The strain probably resulted from direct cat-to-human transmission

Rotavirus strain diversity in the Centre Coast of Tunisia from 2000 through 2003

An epidemiological survey investigating rotavirus infection in children was undertaken in the coastal region of Tunisia from January 2000 through September 2003. A total of 309 fecal specimens were screened by enzyme-linked immunosorbent assay and latex agglutination assay for the presence of group A rotavirus antigen. The detection rate was 26.2%. Rotavirus outbreaks showed a temperature-dependant pattern (P = .026) but no significant association with rainfall. Rotavirus strains isolated were analyzed by RNA polyacrylamide gel electrophoresis and were characterized antigenically by monoclonal antibodies to the VP6 subgroup. Eight RNA electropherotypes were identified, with 3 long and 5 short different RNA profiles. Among VP6 typeable strains, all isolates with a long electrophoretic pattern carried the subgroup II specificity, whereas those with a short profile belonged to subgroup I. In total, 48 rotavirus-positive samples were analyzed for G and P typing by reverse-transcription polymerase chain reaction. A total of 8 different G and P combinations were found: G1P[8] (35.7%), G1P[6] (21.4%), G2P[4] (4.8%), G3P[4] (4.8%), G4P[6] (4.8%), G8P[8] (4.8%), G3P[8] (2.3%), and G4P[8] (2.3%). Mixed infections were detected in 19.1% of stool samples. The emergence in Tunisia of unconventional types, such as G8VP7 specificity, highlights the need for a continual survey of the uncommon strains in North Africa.World Health Organization (V27/181/113 and V27/181/136) and the South African Medical Research Council

Sequence and phylogenetic analyses of human rotavirus strains: Comparison of VP7 and VP8(∗) antigenic epitopes between Tunisian and vaccine strains before national rotavirus vaccine introduction

Group A rotaviruses (RVA) are the leading cause of severe gastroenteritis in infants and young children worldwide. Due to their epidemiological complexity, it is important to compare the genetic characteristics of vaccine strains with the RVA strains circulating before the introduction of the vaccine in the Tunisian immunization program. In the present study, the nucleotide sequences of VP7 and VP8(∗) (n=31), the main targets for neutralizing antibodies, were determined. Comparison of antigenic epitopes of 11 G1P[8], 12 G2P[4], 4 G3P[8], 2 G4P[8], 1 G6P[9] and 1 G12P[8] RVA strains circulating in Tunisia from 2006 to 2011 with the RVA strains present in licensed vaccines showed that multiple amino acid differences existed in or near putative neutralizing domains of VP7 and VP8(∗). The Tunisian G3 RVA strains were found to possess a potential extra N-linked glycosylation site. The Tunisian G4 RVA were closely related to the G4 vaccine strain in RotaTeq, belonging to the same lineage, but the alignment of their VP7 amino acids revealed an insertion of an asparagine residue at position 76 which is close to a glycosylation site (aa 69-71). Despite several differences detected between Tunisian and vaccine strains, which may affect binding of neutralizing antibodies, both vaccines are known to protect against the vast majority of the circulating genotypes, providing an indication of the high vaccine efficiency that can be expected in a future rotavirus immunization program.publisher: Elsevier articletitle: Sequence and phylogenetic analyses of human rotavirus strains: Comparison of VP7 and VP8∗ antigenic epitopes between Tunisian and vaccine strains before national rotavirus vaccine introduction journaltitle: Infection, Genetics and Evolution articlelink: http://dx.doi.org/10.1016/j.meegid.2013.05.008 content_type: article copyright: Copyright © 2013 Elsevier B.V. All rights reserved.status: publishe