Development of multiplex gold nanoparticles biosensors for ultrasensitive detection and genotyping of equine herpes viruses

Abstract Gold nanoparticles (GNPs) biosensors can detect low viral loads and differentiate between viruses types, enabling early diagnosis and effective disease management. In the present study, we developed GNPs biosensors with two different capping agent, citrate-GNPs biosensors and polyvinylpyrrolidone (PVP)-GNPs biosensors for detection of EHV-1 and EHV-4 in multiplex real time PCR (rPCR). Citrate-GNPs and PVP-GNPs biosensors can detect dilution 1010 of EHV-1 with mean Cycle threshold (Ct) 11.7 and 9.6, respectively and one copy as limit of detection, while citrate-GNPs and PVP-GNPs biosensors can detect dilution 1010 of EHV-4 with mean Ct 10.5 and 9.2, respectively and one copy as limit of detection. These findings were confirmed by testing 87 different clinical samples, 4 more samples were positive with multiplex GNPs biosensors rPCR than multiplex rPCR. Multiplex citrate-GNPs and PVP-GNPs biosensors for EHV-1 and EHV-4 are a significant breakthrough in the diagnosis of these virus types. These biosensors offer high sensitivity and specificity, allowing for the accurate detection of the target viruses at very low concentrations and improve the early detection of EHV-1 and EHV-4, leading to faster control of infected animals to prevent the spread of these viruses

Overview of African horse sickness virus (AHSV) situation in Egypt from 2017 to 2022

African horse sickness (AHS) is a non-contagious arthropod-borne infectious disease of Equidae. Because of its severity and quick spread, It is cosidered as a notifiable disease. The current study intended to look into the current suitation of the vector-borne African horse sickness virus (AHSV) in Egypt, determine viral seroprevelance, and assess the associated risk factors. In this context, 2739 sera and 150 spleen samples were collected from different Egyptian governorates and tested for AHSV screening. The sera were investigated for presence of antibodies against AHSV whilst spleen samples were tested for AHSV Ag and RNA detection. The obtained results revealed that all 2739 sera samples tested negative for AHSV antibodies. Furthermore, using ELISA and conventional reverse-transcription polymerase chain reaction (RT-PCR), to identify AHSV Ag and nucleic acid, the 150 tested spleen samples gave negative results with both assays. In conclusion, the recorded results indicated the absence of antibodies, antigen, and viral nucleic acid of AHSV in all tested samples which proved that there is no circulating virus in the investigated Egyptian governorates in the period from 2017 to 2022. Evenually, the effective control programs are recommended by carrying out further epidemiological investigations to understand the current situation of arboviruses in the country

Overview of African horse sickness virus (AHSV) situation in Egypt from 2017 to 2022

African horse sickness (AHS) is a non-contagious arthropod-borne infectious disease of Equidae. Because of its severity and quick spread, It is cosidered as a notifiable disease. The current study intended to look into the current suitation of the vector-borne African horse sickness virus (AHSV) in Egypt, determine viral seroprevelance, and assess the associated risk factors. In this context, 2739 sera and 150 spleen samples were collected from different Egyptian governorates and tested for AHSV screening. The sera were investigated for presence of antibodies against AHSV whilst spleen samples were tested for AHSV Ag and RNA detection. The obtained results revealed that all 2739 sera samples tested negative for AHSV antibodies. Furthermore, using ELISA and conventional reverse-transcription polymerase chain reaction (RT-PCR), to identify AHSV Ag and nucleic acid, the 150 tested spleen samples gave negative results with both assays. In conclusion, the recorded results indicated the absence of antibodies, antigen, and viral nucleic acid of AHSV in all tested samples which proved that there is no circulating virus in the investigated Egyptian governorates in the period from 2017 to 2022. Evenually, the effective control programs are recommended by carrying out further epidemiological investigations to understand the current situation of arboviruses in the country