ABSTRACT
AIMS: To provide a rapid and sensitive method for detecting NoV GI and NoV GII in water and to evaluate the use of the murine norovirus (MNV-1) as a process control. METHODS AND RESULTS: The method is based on viral concentration by filtration on electropositive filters and direct lysis of adsorbed viruses from filters before RNA extraction and RT-qPCR amplification. An one-step multiplex RT-qPCR assay was developed for the simultaneous detection of NoV GI, NoV GII and MNV-1. Then, water samples were artificially contaminated to determine mean virus recoveries and method sensitivity. The method showed a higher sensitivity for detecting NoV GII (10(3) genome copies per 0·5 l) than for NoV GI (10(4) genome copies per 0·5 l) in the presence of MNV-1 regardless of the type of water. The data also showed that MNV-1 is a robust option as process control. CONCLUSIONS: The method described provides a valuable tool for the monitoring of potential public health risks associated with NoV contamination in drinkable water. SIGNIFICANCE AND IMPACT OF STUDY: Given the increasing evidence for NoV involvement in food outbreaks, the one-step multiplex RT-qPCR assay we used in this study would be a very useful tool to investigate NoV contamination in other food products.
ABSTRACT
Poliovirus, the aetiological agent of poliomyelitis, is an enterovirus of the Picronaviridae family. Despite the success of the World Health Organisation (WHO) worldwide vaccination campaign against poliomyelitis, poliovirus remains a public health problem in several developing countries, in Africa and Asia in particular. This is partly due to the considerable capacity of poliovirus strains to circulate and spread in populations with insufficient vaccine coverage. In addition, the attenuated strains of the oral polio vaccine (OPV) may rapidly evolve a neurovirulent phenotype, causing rare cases of paralytic poliomyelitis. The recent occurrence of epidemics associated with vaccine-derived poliovirus (VDPV) has highlighted the emergence of recombinant strains with genomes constituted of sequences from OPV strains together with sequences from non-polio enteroviruses. In this review, after briefly describing the molecular biology of poliovirus and the pathogenesis of poliomyelitis, we will provide an overview of the current situation concerning poliomyelitis prophylaxis and the strategies developed to fight this disease. We will also deal with the issue of the possible re-emergence of poliovirus after declaration of the eradication of wildtype poliovirus.
Subject(s)
Poliomyelitis/genetics , Poliomyelitis/prevention & control , Poliovirus Vaccines/adverse effects , Poliovirus/genetics , Humans , Poliovirus/immunology , Recombination, GeneticABSTRACT
Poliovirus is the causal agent of paralytic poliomyelitis. Flaccid paralysis characteritic of poliomyelitis result from the destruction of motor neurons, the specific target cells of poliovirus in the central nervous system (CNS). The development of new animal and cell models has allowed the key steps of the pathogenesis of poliomyelitis to be investigated at the molecular level. In particular, it has been shown that poliovirus-induced apoptosis is an important component of the tissue injury in the CNS of infected mice that leads to paralysis. In this review, the molecular biology of poliovirus and the pathogenesis of poliomyelitis will be briefly described, and then several models of poliovirus-induced apoptosis will be considered ; the role of the cellular receptor of poliovirus, CD155, in the modulation of apoptosis will also be addressed.
