During 2019, tomato fruits showing viral-like symptoms of marbled yellow spots were abundant in Israel. The new symptoms were distinctive from those typical of tomato brown rugose fruit virus (ToBRFV) infection but resembled symptoms of pepino mosaic virus (PepMV) infection. RT-PCR analysis and the serological tests (enzyme linked immunosorbent assay, western blot and in situ immunofluorescence) revealed and confirmed the presence of both the tobamovirus ToBRFV and the potexvirus PepMV in the symptomatic fruits. A mixture of rod-like and filamentous particles, characteristic of viruses belonging to tobamovirus and potexvirus genera, was visualized by transmission electron microscopy of the tomato fruit viral extract. Sanger sequencing of amplified PepMV-coat protein gene segments showed ~98% sequence identity to the Chilean (CH2)-strain. In a biological assay testing the contribution of traded infected tomatoes to the establishment of tomato plant disease, we applied direct and indirect inoculation modes using Tm-2²-resistant tomato plants. The results, assessed by disease symptom development along with serological and molecular analyses, showed that the ToBRFV and PepMV co-infected fruits were an effective inoculum source for disease spread only when fruits were damaged. Importantly, intact fruits did not spread the viral disease. These results added a new factor to disease epidemiology of these viruses.

Ricin, a protein derived from the seeds of the castor bean plant (Ricinus communis), is a highly lethal toxin that inhibits protein synthesis, resulting in cell death. The widespread availability of ricin, its ease of extraction and its extreme toxicity make it an ideal agent for bioterrorism and self-poisoning. Thus, a rapid, sensitive and reliable method for ricin identification in clinical samples is required for applying appropriate and timely medical intervention. However, this goal is challenging due to the low predicted toxin concentrations in bio-fluids, accompanied by significantly high matrix interferences. Here we report the applicability of a sensitive, selective, rapid, simple and antibody-independent assay for the identification of ricin in body fluids using mass spectrometry (MS). The assay involves lectin affinity capturing of ricin by easy-to-use commercial lactose–agarose (LA) beads, following by tryptic digestion and selected marker identification using targeted LC–MS/MS (Multiple Reaction Monitoring) analysis. This enables ricin identification down to 5 ng/mL in serum samples in 2.5 h. To validate the assay, twenty-four diverse naive- or ricin-spiked serum samples were evaluated, and both precision and accuracy were determined. A real-life test of the assay was successfully executed in a challenging clinical scenario, where the toxin was identified in an abdominal fluid sample taken 72 h post self-injection of castor beans extraction in an eventual suicide case. This demonstrates both the high sensitivity of this assay and the extended identification time window, compared to similar events that were previously documented. This method developed for ricin identification in clinical samples has the potential to be applied to the identification of other lectin toxins.

An outbreak of a disease in camels with skin lesions was reported in Israel during 2016. To identify the etiological agent of this illness, we employed a multidisciplinary diagnostic approach. Transmission electron microscopy (TEM) analysis of lesion material revealed the presence of an orthopox-like virus, based on its characteristic brick shape. The virus from the skin lesions successfully infected chorioallantoic membranes and induced cytopathic effect in Vero cells, which were subsequently positively stained by an orthopox-specific antibody. The definite identification of the virus was accomplished by two independent qPCR, one of which was developed in this study, followed by sequencing of several regions of the viral genome. The qPCR and sequencing results confirmed the presence of camelpox virus (CMLV), and indicated that it is different from the previously annotated CMLV sequence available from GenBank. This is the first reported case of CMLV in Israel, and the first description of the isolated CMLV subtype.

Ricin and abrin are ribosome-inactivating proteins leading to inhibition of protein synthesis and cell death. These toxins are considered some of the most potent and lethal toxins against which there is no available antidote. Digital holographic microscopy (DHM) is a time-lapse, label-free, and noninvasive imaging technique that can provide phase information on morphological features of cells. In this study, we employed DHM to evaluate the morphological changes of cell lines during ricin and abrin intoxication. We showed that the effect of these toxins is characterized by a decrease in cell confluence and changes in morphological parameters such as cell area, perimeter, irregularity, and roughness. In addition, changes in optical parameters such as phase-shift, optical thickness, and effective-calculated volume were observed. These effects were completely inhibited by specific neutralizing antibodies. An enhanced intoxication effect was observed for preadherent compared to adherent cells, as was detected in early morphology changes and confirmed by annexin V/propidium iodide (PI) apoptosis assay. Detection of the dynamic changes in cell morphology at initial stages of cell intoxication by DHM emphasizes the highly sensitive and rapid nature of this method, allowing the early detection of active toxins.

Coronavirus disease (COVID-19) is a contagious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This case report presents a patient who had difficulty eradicating the corona virus due to being treated with Rituximab, which depletes B lymphocyte cells and therefore disables the production of neutralizing antibodies. The combined use of external anti-viral agents like convalescent plasma, IVIG and Remdesivir successfully helped the patient’s immune system to eradicate the virus without B-cell population recovery. In vitro studies showed that convalescent plasma is the main agent that helped in eradicating the virus.

According to the WHO, 75% of the world’s plague cases are found in Madagascar, with an average of 200–700 suspected cases annually (mainly bubonic plague). In 2017, a pneumonic plague epidemic of unusual proportions occurred, which raised several challenges for laboratory confirmation of cases, pointing to the need for the development of Yersinia pestis isolation procedures, especially those that can be performed in remote areas. As the WHO gold standard for plague diagnosis is bacterial culture, we sought to develop a simple method to prepare a highly selective medium, fit for use in remote endemic areas. The performance of the new medium, named improved-BIN, was examined in terms of growth support and selectivity with spiked samples as well in isolating Y. pestis from clinical specimens, and was compared to the results obtained with commercially available selective media. The preparation of the new medium is less complex and its performance was found to be superior to that of first-generation BIN medium. The growth support of the medium is higher, there is no batch diversity, and it maintains high selectivity properties. In 55 clinical specimens obtained from patients suspected to be infected with Y. pestis, approximately 20% more Y. pestis-positive isolates were identified by the improved-BIN than were identified by commercially available selective media. The improved-BIN medium is notably advantageous for the isolation of Y. pestis from clinical specimens obtained from plague patients, thus offering better surveillance tools and proper promotion of medical treatment to more patients suspected of being infected with Y. pestis.