Vincent Porphyre

Vincent Porphyre

orcid

Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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12 September 2013 in PLOS Neglected Tropical Diseases
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Journal Article
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GFGuillaume Le Flohic
Guillaume Le Flohic
VPVincent Porphyre
Vincent Porphyre
PBPhilippe Barbazan
Philippe Barbazan
JGJean-Paul Gonzalez
Jean-Paul Gonzalez
The Japanese encephalitis virus (JEV), an arthropod-born Flavivirus, is the major cause of viral encephalitis, responsible for 10,000–15,000 deaths each year, yet is a neglected tropical disease. Since the JEV distribution area has been large and continuously extending toward new Asian and Australasian regions, it is considered an emerging and reemerging pathogen. Despite large effective immunization campaigns, Japanese encephalitis remains a disease of global health concern. JEV zoonotic transmission cycles may be either wild or domestic: the first involves wading birds as wild amplifying hosts; the second involves pigs as the main domestic amplifying hosts. Culex mosquito species, especially Cx. tritaeniorhynchus, are the main competent vectors. Although five JEV genotypes circulate, neither clear-cut genotype-phenotype relationship nor clear variations in genotype fitness to hosts or vectors have been identified. Instead, the molecular epidemiology appears highly dependent on vectors, hosts' biology, and on a set of environmental factors. At global scale, climate, land cover, and land use, otherwise strongly dependent on human activities, affect the abundance of JEV vectors, and of wild and domestic hosts. Chiefly, the increase of rice-cultivated surface, intensively used by wading birds, and of pig production in Asia has provided a high availability of resources to mosquito vectors, enhancing the JEV maintenance, amplification, and transmission. At fine scale, the characteristics (density, size, spatial arrangement) of three landscape elements (paddy fields, pig farms, human habitations) facilitate or impede movement of vectors, then determine how the JEV interacts with hosts and vectors and ultimately the infection risk to humans. If the JEV is introduced in a favorable landscape, either by live infected animals or by vectors, then the virus can emerge and become a major threat for human health. Multidisciplinary research is essential to shed light on the biological mechanisms involved in the emergence, spread, reemergence, and genotypic changes of JEV.

1 November 2009 in Preventive Veterinary Medicine
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Journal Article
Open access
SCS. Costard
S. Costard
VPVincent Porphyre
Vincent Porphyre
SMS. Messad
S. Messad
SRS. Rakotondrahanta
S. Rakotondrahanta
HVH. Vidon
H. Vidon
DPDirk Udo Pfeiffer
Dirk Udo Pfeiffer
A cross-sectional study was carried out in 2005 and 2006 in three geographical areas of Madagascar to investigate and differentiate swine farm management and biosecurity practices in smallholder farming communities. Questionnaire data from a total of 709 pig farms were analysed using multiple factor analysis (MFA) and hierarchical cluster analysis (HCA). Variables describing management and biosecurity practices were organised into five groups: structure of the farm, animal-contacts, person- and vehicle-contacts, feeding, and sanitary aspects. In general, few biosecurity measures were implemented in the pig farms included in the study. Regional differences in management and biosecurity practices emerged from the MFA and were mainly due to, in order of decreasing importance: structure of the farm, sanitary aspects, feeding and animal-contacts and, to a lesser extent, person- and vehicle-contacts. HCA resulted in the differentiation of four distinct types of farms in each of two study areas, Arivonimamo and Marovoay, while no grouping could be identified amongst farms in Ambatondrazaka area. The characterisation of the different types of smallholder pig farms will allow adapting recommendations on husbandry practices and control measures in pig farms of these regions of Madagascar. The development of tailored recommendations is essential for Malagasy smallholders who have limited resources and need to make evidence-based management changes to reduce the risk of contagious diseases in their herds.

6 February 2013 in The American Journal of Tropical Medicine and Hygiene
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Journal Article
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STSarah Temmam
Sarah Temmam
LBLydia Besnard
Lydia Besnard
SASoa Fy Andriamandimby
Soa Fy Andriamandimby
CFCoralie Foray
Coralie Foray
HRHarentsoaniaina Rasamoelina-Andriamanivo
Harentsoaniaina Rasamoelina-Andriamanivo
VPVincent Porphyre
Vincent Porphyre
Hepatitis E virus (HEV) causes an orofecal disease transmitted through poor hygiene environments, contaminated food (mainly pork products), or by contacts with infected animals. Very little data are currently available regarding the disease in the Southwestern Indian Ocean Islands. We report the first sero- and viro-survey for HEV in human and swine in Madagascar. A seroprevalence rate of 14.1% (60 of 427) was measured in slaughterhouse workers. Seroprevalence to HEV in pigs was estimated to 71.2% (178 of 250), strongly suggesting the existence of a zoonotic cycle. Three out of 250 pig livers (1.2%) tested HEV RNA-positive by quantitative polymerase chain reaction. Phylogenetic analyses based on 1-kb sequences of the ORF 2-3 identified these viruses as HEV genotype 3. Sequences clustered in a distinct Malagasy sub-clade, possibly representative of a new sub-genotype, for which the date of emergence was estimated around 1989. Further studies are needed to confirm other transmission routes of HEV to humans, especially through non-zoonotic cycles.

30 April 2023 in Animals
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Journal Article
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Claude SaegermanClaude Saegerman
Claude Saegerman
GPGianni Parisi
Gianni Parisi
JNJarkko Niemi
Jarkko Niemi
MHMarie-France Humblet
Marie-France Humblet
JRJorge Washington Ron-Román
Jorge Washington Ron-Román
VRVéronique Renault
Véronique Renault
Disease prevention, including biosecurity, surveillance, and traceability are key aspects to minimize the risk of animal diseases causing harm to society. Diseases for which biosecurity are needed depend on species of interest, e.g., African swine fever, avian influenza, or foot-and-mouth disease. However, several definitions of biosecurity co-exist in the literature. Under the new COST Action “Biosecurity Enhanced Through Training Evaluation and Raising Awareness” (BETTER) CA20103, we launched an initial survey on the agreement with eight existing definitions of (livestock) biosecurity, to rank keywords to consider before attempting a more consolidated definition, and to select the desirable qualities of a definition of livestock biosecurity. Respondents (N = 316) had a male–female gender ratio close to one, were mostly between 25 and 54 years old, and had animal health as the main field of expertise (30% were government officials). The significant most popular biosecurity definition was the one that conceptualized the rules of 5B’s (bio-exclusion, bio-containment, bio-compartmentation, bio-prevention, and bio-preservation). The top two keywords to consider for the consolidation of the biosecurity definition were “prevention” and “measures”. The optimal biosecurity definition needs to be operational and related to animal health but also comprehensible, simple, and related to public health. The survey results highlight the need for the integration of more aspects in the existing definitions of livestock biosecurity (prevention of zoonoses and preservation of the environment and diversity).

1 November 2013 in Trends in Parasitology
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Journal Article
Closed access
HRHarentsoaniaina Rasamoelina-Andriamanivo
Harentsoaniaina Rasamoelina-Andriamanivo
VPVincent Porphyre
Vincent Porphyre
RJRonan Jambou
Ronan Jambou

1 March 2016 in Veterinary Parasitology
Verified
Journal Article
Open access
VPVincent Porphyre
Vincent Porphyre
MBM. Betson
M. Betson
HRH. Rabezanahary
H. Rabezanahary
YMY. Mboussou
Y. Mboussou
NZN.J. Zafindraibe
N.J. Zafindraibe
AMA. Michault
A. Michault
Taenia solium cysticercosis was reported in official veterinary and medical statistics to be highly prevalent in pigs and humans in Madagascar, but few estimates are available for pigs. This study aimed to estimate the seroprevalence of porcine cysticercosis among pigs slaughtered in Antananarivo abattoirs. Firstly, the diagnostic performance of two antigen-ELISA techniques (B158B60 Ag-ELISA and HP10 Ag-ELISA) and an immunoblotting method were compared with meat inspection procedures on a sample of pigs suspected to be infected with (group 1; n = 250) or free of (group 2; n = 250) T. solium based on direct veterinary inspection in Madagascar. Sensitivity and specificity of the antigen ELISA5 were then estimated using a Bayesian approach for detection of porcine cysticercosis in the absence of a gold standard. Then, a third set of pig sera (group 3, n = 250) was randomly collected in Antananarivo slaughterhouses and tested to estimate the overall prevalence of T. solium contamination in pork meat traded in Antananarivo. The antigen ELISAs showed a high sensitivity (>84%), but the B158B60 Ag-ELISA appeared to be more specific than the HP10 Ag-ELISA (model 1: 95% vs 74%; model 2: 87% vs 71%). The overall prevalence of porcine cysticercosis in Antananarivo slaughterhouses was estimated at 2.3% (95% credibility interval [95%CrI]: 0.09-9.1%) to 2.6% (95%CrI: 0.1-10.3%) depending on the model and priors used. Since the sample used in this study is not representative of the national pig population, village-based surveys and longitudinal monitoring at slaughter are needed to better estimate the overall prevalence, geographical patterns and main risk factors for T. solium contamination, in order to improve control policies. (C) 2015 Elsevier B.V. All rights reserved.