Development of Rapid and Specific Detection for the Human Aichivirus A Using the Loop-Mediated Isothermal Amplification from Water Samples

A review of nucleic acid-based detection methods for foodborne viruses: Sample pretreatment and detection techniques

Viruses are major pathogens that cause food poisoning when ingested via contaminated food and water. Therefore, the development of foodborne virus detection technologies that can be applied throughout the food distribution chain is essential for food safety. A common nucleic acid-based detection method is polymerase chain reaction (PCR), which has become the gold standard for monitoring food contamination by viruses due to its high sensitivity, and availability of commercial kits. However, PCR-based methods are labor intensive and time consuming, and are vulnerable to inhibitors that may be present in food samples. In addition, the methods are restricted with regard to site of analysis due to the requirement of expensive and large equipment for sophisticated temperature regulation and signal analysis procedures. To overcome these limitations, optical and electrical readout biosensors based on nucleic acid isothermal amplification technology and nanomaterials have emerged as alternatives for nucleic acid-based detection of foodborne viruses. Biosensors are promising portable detection tools owing to their easy integration into compact platforms and ability to be operated on-site. However, the complexity of food components necessitates the inclusion of tedious preprocessing steps, and the lack of stability studies on residual food components further restricts the practical application of biosensors as a universal detection method. Here, we summarize the latest advances in nucleic acid-based strategies for the detection of foodborne viruses, including PCR-based and isothermal amplification-based methods, gene amplification-free methods, as well as food pretreatment methods. The principles, strengths/disadvantages, and performance of each method, problems to be solved, and future prospects for the development of a universal detection method are discussed.

Development of a highly sensitive and rapid detection method for Pea enation mosaic virus using loop-mediated isothermal amplification assay

The Pea enation mosaic virus (PEMV) has infected plants in the family Leguminosae such as pea, chickpea, faba bean, and lentil plants worldwide that the virus can be transmitted by sap, aphids, and seeds. Among the damages that PEMV disease cause in plants are reduced crop productivity, severely misshapen pods, wart-like outgrowths or proliferation on the surface. Previously, enzyme-linked immunosorbent assay (ELISA), reverse transcription (RT)-nested polymerase chain reaction (PCR), and real-time PCR had been used to detect PEMV. However, these methods are time-consuming and require specific equipments. For this reason, the development of a highly specific and sensitive detection method has become necessary. In this study, a new method for PEMV-1 using the loop-mediated isothermal amplification (LAMP) assay has been developed with specific primer sets as inner- and outer primers. Results showed PEMV-1 has been successfully detected that LAMP could confirm a diluted PEMV-1 up to 10-6 cDNA. LAMP is about 10,000 times more sensitive than the RT-nested PCR and/or real-time PCR. Moreover, the processing time of the LAMP was decreased 3 h than RT-nested PCR. Although future validation will be required to confirm enablement in the field area, this study provides a valuable method to identify PEMV-1 that could offer some advantages including rapid detection, high specificity and high sensitivity than others.

A Comprehensive Review on Human Aichi Virus

Although norovirus, rotavirus, adenovirus and Astrovirus are considered the most important viral agents transmitted by food and water, in recent years other viruses, such as Aichi virus (AiV), have emerged as responsible for gastroenteritis outbreaks associated with different foods. AiV belongs to the genus Kobuvirus of the family Picornaviridae. It is a virus with icosahedral morphology that presents a single stranded RNA genome with positive sense (8280 nucleotides) and a poly (A) chain. AiV was first detected from clinical samples and in recent years has been involved in acute gastroenteritis outbreaks from different world regions. Furthermore, several studies conducted in Japan, Germany, France, Tunisia and Spain showed a high prevalence of AiV antibodies in adults (between 80% and 99%), which is indicative of a large exposure to this virus. The aim of this review is to bring together all the discovered information about the emerging pathogen human Aichi virus (AiV), discussing the possibles routes of transmission, new detection techniques and future research. Although AiV is responsible for a low percentage of gastroenteritis outbreaks, the high seroprevalence shown by human populations indicates an evident role as an enteric agent. The low percentage of AiV detection could be explained by the fact that the pathogen is more associated to subclinical infections. Further studies will be needed to clarify the real impact of AiV in human health and its importance as a causative gastroenteritis agent worldwide.