clove and Enterovirus-Infections

Poliomyelitis outbreaks due to pathogenic vaccine-derived polioviruses (VDPVs) are threatening and complicating the global polio eradication initiative. Most of these VDPVs are genetic recombinants with non-polio enteroviruses (NPEVs) of species C. Little is known about factors favoring this genetic macroevolution process. Since 2001, Madagascar has experienced several outbreaks of poliomyelitis due to VDPVs, and most of VDPVs were isolated in the south of the island. The current study explored some of the viral factors that can promote and explain the emergence of recombinant VDPVs in Madagascar.. Between May to August 2011, we collected stools from healthy children living in two southern and two northern regions of Madagascar. Virus isolation was done in RD, HEp-2c, and L20B cell lines, and enteroviruses were detected using a wide-spectrum 5'-untranslated region RT-PCR assay. NPEVs were then sequenced for the VP1 gene used for viral genotyping.. Overall, we collected 1309 stools, of which 351 NPEVs (26.8%) were identified. Sequencing revealed 33 types of viruses belonging to three different species: Enterovirus A (8.5%), Enterovirus B (EV-B, 40.2%), and Enterovirus C (EV-C, 51.3%). EV-C species included coxsackievirus A13, A17, and A20 previously described as putative recombination partners for poliovirus vaccine strains. Interestingly, the isolation rate was higher among stools originating from the South (30.3% vs. 23.6%, p-value = 0.009). EV-C were predominant in southern sites (65.7%) while EV-B predominated in northern sites (54.9%). The factors that explain the relative abundance of EV-C in the South are still unknown.. Whatever its causes, the relative abundance of EV-C in the South of Madagascar may have promoted the infections of children by EV-C, including the PV vaccine strains, and have favored the recombination events between PVs and NPEVs in co-infected children, thus leading to the recurrent emergence of recombinant VDPVs in this region of Madagascar.

Topics: Child; Disease Outbreaks; Enterovirus; Enterovirus C, Human; Enterovirus Infections; Humans; Madagascar; Phylogeny; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Oral; Poliovirus Vaccines

Human enteroviruses of species A (EV-A) are the leading cause of hand-foot-and-mouth disease (HFMD). EV-A71 is frequently implicated in HFMD outbreaks and can also cause severe neurological manifestations. We investigated the molecular epidemiological processes at work and the contribution of genetic recombination to the evolutionary history of EV-A in Madagascar, focusing on the recently described EV-A71 genogroup F in particular. Twenty-three EV-A isolates, collected mostly in 2011 from healthy children living in various districts of Madagascar, were characterized by whole-genome sequencing. Eight different types were identified, highlighting the local circulation and diversity of EV-A. Comparative genome analysis revealed evidence of frequent recent intra- and intertypic genetic exchanges between the noncapsid sequences of Madagascan EV-A isolates. The three EV-A71 isolates had different evolutionary histories in terms of recombination, with one isolate displaying a mosaic genome resulting from recent genetic exchanges with Madagascan coxsackieviruses A7 and possibly A5 and A10 or common ancestors. The engineering and characterization of recombinants generated from progenitors belonging to different EV-A types or EV-A71 genogroups with distantly related nonstructural sequences indicated a high level of permissiveness for intertypic genetic exchange in EV-A. This permissiveness suggests that the primary viral functions associated with the nonstructural sequences have been highly conserved through the diversification and evolution of the EV-A species. No outbreak of disease due to EV-A has yet been reported in Madagascar, but the diversity, circulation, and evolution of these viruses justify surveillance of EV-A circulation and HFMD cases to prevent possible outbreaks due to emerging strains.

Topics: Animals; Cell Line; Cell Line, Tumor; Child, Preschool; Chlorocebus aethiops; Disease Outbreaks; Enterovirus A, Human; Enterovirus Infections; Evolution, Molecular; Genome, Viral; Genotype; Hand, Foot and Mouth Disease; HEK293 Cells; Humans; Madagascar; Molecular Epidemiology; Permissiveness; Phylogeny; Recombination, Genetic; Vero Cells; Whole Genome Sequencing

Four poliomyelitis outbreaks caused by vaccine-derived polioviruses have been reported recently, including one in Madagascar in 2002. In all cases, the viral strains involved were recombinant between poliovirus vaccine strains and nonpoliovirus strains, probably enterovirus species C. Nevertheless, little is known about the circulation and epidemiology of enteroviruses in the regions where these outbreaks occurred. To assess the circulation of enteroviruses (particularly enterovirus species C) in Madagascar, we genetically characterized 55 enterovirus strains isolated between 1994 and 2002. The strains were identified and compared by partially sequencing the region encoding the VP1 capsid protein. Phylogenetic analysis and pairwise comparison with prototype enterovirus strains distinguished two different species: 25 isolates belonged to human enterovirus B species, and 30 isolates were identified as coxsackievirus A13, A15, A17, A18, A20, A21, and A24, belonging to the human enterovirus species C. The relatively high frequency and the wide distribution of species C coxsackie A viruses in different regions of Madagascar suggest that they had been silently and widely circulating in the country during the whole study period. The circulation of coxsackie A viruses, combined with the low routine oral polio vaccine coverage, may have played a role in the emergence of the recent outbreak in Madagascar.

Topics: Amino Acid Sequence; Cell Line, Tumor; DNA-Binding Proteins; Enterovirus C, Human; Enterovirus Infections; Humans; Madagascar; Molecular Sequence Data; Phylogeny; Plant Proteins; Sequence Analysis, DNA; Trans-Activators; Transcription Factors

Enteroviruses, members of the family Picornaviridae, are responsible for a wide variety of diseases and represent a major public health hazard. Typing of non polio enterovirus (NPEV) infection is traditionally based on a serum neutralization assay. However, this method is time-consuming, labor-intensive, expensive, and may fail to identify antigenic variation. A new molecular typing involving partial sequencing of the genome has been recently developed. In this study, 46 NPEV strains were analyzed, including 37 antigenicaly "untypeable" viruses. Partial sequencing of the C-end of the viral capsid protein VP1 and pairwise identity with the prototype strains allow us to assign a serotype for all "untypeable" viruses. The results show a large number and wide variety of Coxsackieviruses A which belong to the HEV-C species and also Echoviruses and Coxsackieviruses B of the HEV-B species. This method may be useful to identify all NPEV serotypes in Madagascar and to assess the possible impact of circulating NPEV populations, as we enter the final stage of poliomyelitis eradication.

Topics: DNA, Viral; Enterovirus; Enterovirus Infections; Humans; Madagascar; Molecular Epidemiology; Sensitivity and Specificity; Sequence Analysis, Protein; Serotyping; Viral Fusion Proteins

An epidemic of A.E.H.C. was broken out everywhere in Madagascar during hot season from September 1990 to May 1991 with an important acuteness in February and March. Clinical symptoms are those of A.E.H.C. to enterovirus with some particularities. Virological study shows cytopathogenic effect of enterovirus and microbiology shows the existence of several bacterial germs particularly staphylococcus epidermidis. The discovery of two cases of streptococcus pneumonia and the absence of chlamydia trachomatis make the originality of our cases. The efficacy of the association antibiotic and steroids is spectacular.

Topics: Conjunctivitis, Acute Hemorrhagic; Enterovirus Infections; Humans; Madagascar; Staphylococcal Infections; Streptococcal Infections

Our study included a total of 318 diarrheic stools and 52 normal stools collected from out-patients with acute diarrhea at welfare Center and children admitted at Antananarivo City children's Hospital, or control free of infectious disease during 8 months period. Enzyme linked immunosorbant assay and tissue cultures revealed the presence of 152 viral particles (47%) from children with diarrhea and 29 viral particles (55%) from control children. Positive cases were distributed according age, sex, and season factors. The highest infection rate was found in 25-36 months old of the children with diarrhea (72%). The two sexes were equally infected. Enteroviruses were isolated from diarrheic stools with a high frequency (43%) during the rainy and warm season while Rotaviruses were the prevailing agent during the dry and cool season, and Adenoviruses came in second place (19%). In view of our results, the etiological role of these viruses in diarrhea is discussed.

Topics: Adenoviridae; Adenoviridae Infections; Child, Preschool; Diarrhea, Infantile; Enterovirus; Enterovirus Infections; Feces; Female; Humans; Infant; Infant, Newborn; Madagascar; Male; Rotavirus; Rotavirus Infections; Seasons; Virus Diseases

Topics: Age Factors; Carrier State; Child, Preschool; Enterovirus; Enterovirus Infections; Feces; Female; Humans; Infant; Madagascar; Male; Sex Factors

Topics: Adolescent; Adult; Child; Child, Preschool; Enterovirus; Enterovirus B, Human; Enterovirus Infections; Female; History, 20th Century; Humans; Infant; Madagascar; Male; Poliovirus; Virology