Virus Concentration Research Articles

Detection of Human Adenovirus and Rotavirus in Wastewater in Lusaka, Zambia: Demonstrating the Utility of Environmental Surveillance for the Community.

Enteric infections due to viral pathogens are a major public health concern. Detecting the risk areas requires a strong surveillance system for pathogenic viruses in sources such as wastewater. Towards building an environmental surveillance system in Zambia, we aimed to identify group A rotavirus (RVA) and human adenovirus (HAdV) in wastewater. Convenient sampling was conducted at four study sites every Tuesday for five consecutive weeks. The research team focused on three different methods of viral concentration to determine the suitability in terms of cost and applicability for a regular surveillance system: the bag-mediated filtration system (BMFS), polyethylene glycol-based (PEG) precipitation, and skimmed milk (SM) flocculation. We screened 20 wastewater samples for HAdV and RVA using quantitative polymerase chain reaction (qPCR) and conventional polymerase chain reaction (cPCR). Of the 20 samples tested using qPCR, 18/20 (90%) tested positive for HAdV and 14/20 (70%) tested positive for RVA. For the genetic sequencing, qPCR positives were subjected to cPCR, of which 12 positives were successfully amplified. The human adenovirus was identified with a nucleotide identity range of 98.48% to 99.53% compared with the reference genome from GenBank. The BMFS and SM flocculation were the most consistent viral concentration methods for HAdV and RVA, respectively. A statistical analysis of the positives showed that viral positivity differed by site (p < 0.001). SM and PEG may be the most appropriate options in resource-limited settings such as Zambia due to the lower costs associated with these concentration methods. The demonstration of HAdV and RVA detection in wastewater suggests the presence of the pathogens in the communities under study and the need to establish a routine wastewater surveillance system for the identification of pathogens.

Statistical analysis of infectious disease transmission risk based on exhaled respiratory droplet trajectory distribution

In the present work, the risk of infectious disease transmission is evaluated based on a statistical analysis of respiratory droplet trajectory distribution. An analytical model recently developed by the authors allows the prediction of the trajectory and evaporation rate of exhaled droplets. The model is used to collect data from a sampling set of more than twenty thousand droplets distributed over a range of diameters from 0.1 μm to 1 mm for different respiratory scenarios. The analytical tool implements the governing equations of droplet transport, evaporation, energy balance, and chemical composition. It also features a two-dimensional unsteady empirical model of respiratory cloud including momentum dissipation and buoyancy. A discrete random walk approach to simulate the droplet turbulent dispersion, and the randomization of the droplet release within the exhalation period and the mouth cross section area complete the model enabling statistical analyses to be rightly performed. With the due boundary conditions, different types of respiratory events can be modeled easily. With additional information on the exhaled droplet size distribution and viral content, spatial maps of virus concentration are derived and associated with the risk of infectious disease transmission being able to discriminate between various transmission routes such as fomite, airborne, or direct inhalation. Different scenarios are presented including mouth breathing, nose breathing, speaking, coughing, and sneezing. The fluid dynamic behavior of respiratory droplets is explored on a size basis, and the role of ventilation discussed. Risk evaluation provides useful information for a knowledgeable discussion on the prevention needs and means from case to case.

Development of a simple and highly sensitive virion concentration method to detect SARS-CoV-2 in saliva

BackgroundControlling novel coronavirus pandemic infection (COVID-19) is a global challenge, and highly sensitive testing is essential for effective control. The saliva is a promising sample for high-sensitivity testing because it is easier to collect than nasopharyngeal swab samples and allows large-volume testing. ResultsWe developed a simple SARS-CoV-2 concentration method from saliva samples that can be completed in less than 60 min. We performed a spike test using 12 ml of saliva samples obtained from healthy volunteer people, and the developed method performance was evaluated by comparison using a combination of automatic nucleic acid extraction followed by RT-qPCR detection. In saliva spike tests using a 10-fold dilution series of SARS-CoV-2, the developed method was consistently 100-fold more sensitive than the conventional method. ConclusionsThe developed method can improve the analytical sensitivity of the SARS-CoV-2 test using saliva and speed up and save labor in screening tests by pooling many samples. Furthermore, the developed method has the potential to contribute to the highly sensitive detection of various human and animal viral pathogens from the saliva and various clinical samples.

Explaining the impact of mutations on quantification of SARS-CoV-2 in wastewater

Wastewater surveillance is an effective tool for monitoring community spread of COVID-19 and other diseases. Quantitative PCR (qPCR) analysis for wastewater surveillance is more susceptible to mutations in target genome regions than binary PCR analysis for clinical surveillance. The SARS-CoV-2 concentrations in wastewater estimated by N1 and N2 qPCR assays started to diverge around July 2022 in data from different sampling sites, analytical methods, and analytical laboratories in Japan. On the basis of clinical genomic surveillance data and experimental data, we demonstrate that the divergence is due to two mutations in the N1 probe region, which can cause underestimation of viral concentrations. We further show that this inaccuracy can be alleviated if the qPCR data are analyzed with the second derivative method or the Cy0 method instead of the crossing point method.

The Influence of Ewom and Fear of Missing Out in the Intention to Buy Skincare Products Through Tiktok

The current social media platform provide a variety of social content that raises new phenomena to become viral and beauty content is one of the most popular content. This study examines the influence of eWOM and Fear of Missing Out (FOMO) in the purchase intention of Skintific skincare products through TikTok. To understand the influence of eWOM, this study combines the information adoption model with self-determination theory as a theoretical basis. Data collection was conducted by an online survey with a purposive sampling method using 235 selected respondents. The data was then processed by applying PLS-SEM to test the proposed hypotheses. The findings show that information usefulness has a positive effect on information adoption, information adoption and FOMO have a positive effect on purchase intention, information credibility and information quantity have a positive effect on information usefulness, and information quality has no significant effect on information usefulness. The direct managerial implication of this finding be a valuable addition to the academic understanding of FOMO in the information adoption model and provide direction for companies in formulating digital marketing designs that focus on the credibility and frequency of content broadcast to provoke consumer desire to use the company's products so as not to be left behind by others.

Investigates the ability of plant extracts from Lens culinaris to protect zucchini from the Zucchini yellow mosaic virus (ZYMV)

Evaluate the impact of extracts from the Lens culinaris plant on a number of physiological and biochemical parameters in squash leaves infected with ZYMV in this work. Compared to the untreated leaves, ZYMV infected leaves showed a range of symptoms, such as severe mosaic, size reduction, stunting, and deformation. Analysis of physiological data revealed that L. culinaris extract lectin therapies and viral infections had an impact on metabolism. Protein, carbohydrate, and pigment levels were all lowered by viral infection. However, phenolic compounds, total protein, total carbohydrates, total amino acids, proline, total chlorophyll and peroxidases levels are considerably elevated with all extract therapies. The other biochemical parameters also displayed a variety of changes. Moreover shoot length, number of leaves and number of flowers was significantly increased compared to viral control in all treatments. The L. culinaris extract treatment increases the plant’s ZYMV resistance. This is detectable through reduction of the plants treated with lentil lectin pre and post virus inoculation, reduction in disease severity and viral concentration, and percentage of the infected plants has a virus. All findings demonstrate significant metabolic alterations brought by viral infections or L. culinaris extract treatments, and they also suggest that exogenous extract treatments is essential for activating the body’s defences against ZYMV infection.

Premature Activation of the HIV-1 Protease Is Influenced by Polymorphisms in the Hinge Region.

HIV-1 protease inhibitors are an essential component of antiretroviral therapy. However, drug resistance is a pervasive issue motivating a persistent search for novel therapies. Recent reports found that when protease activates within the host cell's cytosol, it facilitates the pyroptotic killing of infected cells. This has led to speculation that promoting protease activation, rather than inhibiting it, could help to eradicate infected cells and potentially cure HIV-1 infection. Here, we used a nanoscale flow cytometry-based assay to characterize protease resistance mutations and polymorphisms. We quantified protease activity, viral concentration, and premature protease activation and confirmed previous findings that major resistance mutations generally destabilize the protease structure. Intriguingly, we found evidence that common polymorphisms in the hinge domain of protease can influence its susceptibility to premature activation. This suggests that viral heterogeneity could pose a considerable challenge for therapeutic strategies aimed at inducing premature protease activation in the future.

Airborne Influenza Virus in Daycare Centers.

In this study, we investigated the concentration of airborne influenza virus in daycare centers and influencing factors, such as common cold prevalence, air pollutants, and meteorological factors. A total of 209 air samples were collected from daycare centers in Kaohsiung and the influenza virus was analyzed using real-time quantitative polymerase chain reaction. Air pollutants and metrological factors were measured using real-time monitoring equipment. Winter had the highest positive rates of airborne influenza virus and the highest prevalence of the common cold, followed by summer and autumn. The concentration of CO was significantly positively correlated with airborne influenza virus. Daycare center A, with natural ventilation and air condition systems, had a higher concentration of airborne influenza A virus, airborne fungi, and airborne bacteria, as well as a higher prevalence of the common cold, than daycare center B, with a mechanical ventilation system and air purifiers, while the concentrations of CO2, CO, and UFPs in daycare center A were lower than those in daycare center B. We successfully detected airborne influenza virus in daycare centers, demonstrating that aerosol sampling for influenza can provide novel epidemiological insights and inform the management of influenza in daycare centers.

Analytical validation of a semi-automated methodology for quantitative measurement of SARS-CoV-2 RNA in wastewater collected in northern New England.

Wastewater-based epidemiology (WBE) can be used to monitor the community presence of infectious disease pathogens of public health concern such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Viral nucleic acid has been detected in the stool of SARS-CoV-2-infected individuals. Asymptomatic SARS-CoV-2 infections make community monitoring difficult without extensive and continuous population screening. In this study, we validated a procedure that includes manual pre-processing, automated SARS-CoV-2 RNA extraction and detection workflows using both reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR) and reverse transcriptase droplet digital PCR (RT-ddPCR). Genomic RNA and calibration materials were used to create known concentrations of viral material to determine the linearity, accuracy, and precision of the wastewater extraction and SARS-CoV-2 RNA detection. Both RT-qPCR and RT-ddPCR perform similarly in all the validation experiments, with a limit of detection of 50 copies/mL. A wastewater sample from a care facility with a known outbreak was assessed for viral content in replicate, and we showed consistent results across both assays. Finally, in a 2-week survey of two New Hampshire cities, we assessed the suitability of our methods for daily surveillance. This paper describes the technical validation of a molecular assay that can be used for long-term monitoring of SARS-CoV-2 in wastewater as a potential tool for community surveillance to assist with public health efforts.IMPORTANCEThis paper describes the technical validation of a molecular assay that can be used for the long-term monitoring of SARS-CoV-2 in wastewater as a potential tool for community surveillance to assist with public health efforts.

An entropy-based study on the mutational landscape of SARS-CoV-2 in USA: Comparing different variants and revealing co-mutational behavior of proteins

COVID-19 emergency has pushed the international scientific community to use every resource to combat the spread of the virus, to understand its biology and predict its possible evolution in terms of new variants. Since the first SARS-CoV-2 virus nucleotide and amino acid sequences were made available, information theory was used to study how viral information content was changing over time and then trace the evolution of its mutational landscape. In this work we analyzed SARS-CoV-2 sequences collected mainly in the USA in a period from March 2020 until December 2022 and computed mutation profiles of viral proteins over time through an entropy-based approach using Shannon Entropy and Hellinger distance. This representation allows an at-a-glance view of the mutational landscape of viral proteins over time and can provide new insights on the evolution of the virus from different points of view. Non-structural proteins typically showed flat mutation profiles, characterized by a very low Average mutation Entropy, while accessory and structural proteins showed mostly non uniform and high mutation profiles, often coupled with the predominance of variants. Interestingly NSP2 protein, whose function is currently still debated, falls in the same branch of NSP14 and NSP10 in the phylogenetic tree of mutations constructed through correlations of mutation profiles, suggesting a co-evolution of those proteins and a possible functional link with each other. To the best of our knowledge this is the first study based on a massive amount of data (n = 107,939,973) that analyzes from an entropy point of view the mutational landscape of SARS-CoV-2 over time and depicts a mutational temporal profile of each protein of the virus.

Pepper mild mottle virus intended for use as a process indicator for drinking water treatment: Present forms and quantitative relations to norovirus and rotavirus in surface water

Pepper mild mottle virus (PMMoV) has been proposed as a potential indicator of human enteric viruses in environmental water and for viral removal during drinking water treatment. To investigate the occurrence and present forms of PMMoV and quantitative relations to norovirus GII and rotavirus A (RVA) in surface waters, 147 source water samples were collected from 21 drinking water treatment plants (DWTPs) in Japan between January 2018 and January 2021, and the concentrations of viruses in suspended and dissolved fractions were measured using real-time RT-PCR. PMMoV was detected in 81–100 % of samples in each sample month and observed concentrations ranged from 3.0 to 7.0 log10 copies/L. The concentrations of PMMoV were higher in dissolved fraction compared to suspended fractions, while different partitioning was observed for NoV GII depending on seasons. The concentrations of PMMoV were basically higher than those of norovirus GII (1.9−5.3 log10 copies/L) and RVA (1.9−6.6 log10 copies/L), while in 18 samples, RVA presented higher concentrations than PMMoV. Partial regions of VP7, VP4, and VP6 of the RVA in the 18 samples were amplified using nested PCR, and the genotypes were determined using an amplicon-based next-generation sequencing approach. We found that these source water samples included not only human RVA but also various animal RVA and high genetic diversity due to the existence of animal RVA was associated with a higher RVA concentration than PMMoV. Our findings suggest that PMMoV can be used as an indicator of norovirus GII and human RVA in drinking water sources and that the indicator performance should be evaluated by comparing to zoonotic viruses as well as human viruses.

A fieldable process for sensitive detection of airborne viruses via electrophoresis-based RNA enrichment

Sensitive on-site virus detection is a requirement for timely action against the spread of airborne infection since ultra-low in-air viral concentrations can readily infect individuals when inhaled. Here, we consider a fieldable biosensing process that incorporates a fast RNA enrichment step in order to concentrate viral RNA in a small volume prior to RT-qPCR. The enrichment approach uses electrophoresis in an RT-qPCR-compatible buffer, and allows for concentration of RNA by nearly 5-fold within only 10 min. In order to place this performance into context, we analyzed the minimum detectable concentration of a low-cost, fieldable, biosensing process that uses electrostatic precipitation for air sampling, heating for viral RNA extraction, and then RNA enrichment, followed by RT-qPCR. With enrichment, we estimated an in-air concentration of 5,654 genome copies (gc)/m3 with a 100% detection rate and an in-air concentration of 4,221 gc/m3 with a 78.6% detection rate. Given that the concentrations of common viruses, such as influenza and SARS-CoV-2, in several indoor spaces are between 5,800 and 37,000 gc/m3, we conclude that enrichment allows a detection that is sufficiently sensitive for practical applications.

Resolving the Loss of Intermediate-Size Speech Aerosols in Funnel-Guided Particle Counting Measurements

Modeling of airborne virus transmission and protection against it requires knowledge of the amount of biofluid emitted into the atmosphere and its viral load. Whereas viral concentrations in biofluids are readily measured by quantitative PCR, the total volume of fluids aerosolized during speaking, as measured by different researchers using various technologies, differs by several orders of magnitude. We compared collection methods in which the aerosols first enter into a low-humidity chamber either by direct injection or via commonly used funnel and tubing arrangements, followed by standard optical particle sizer measurement. This “collect first, measure later” approach sacrifices the recording of the temporal correlation between aerosol generation and sound types such as plosives and vowels. However, the direct-injection mode prevents inertia deposition associated with the funnel arrangements and reveals far more intermediate-size (5–20 μm in diameter) particles that can dominate the total mass of ejected respiratory aerosol. The larger aerosol mass observed with our method partially reconciles the large discrepancy between the SARS-CoV-2 infectious dose estimated from superspreader event analyses and that from human challenge data. Our results also impact measures to combat airborne virus transmission because they indicate that aerosols that settle faster than good room ventilation rates can dominate this process.

A pre-post evaluation study of a social media-based COVID-19 communication campaign to improve attitudes and behaviors toward COVID-19 vaccination in Tanzania.

In Tanzania, the One by One: Target COVID-19 campaign was launched nationally in July 2022 to address the prevalent vaccine hesitancy and lack of confidence in COVID-19 vaccines. The campaign mobilized social media influencers and viral content with the ultimate goal of increasing COVID-19 vaccine uptake in the country. The objective of this study was to empirically assess the impact of the campaign on three outcomes: vaccine confidence, vaccine hesitancy, and vaccination status. Using programmatic data collected through an online survey before and after the campaign, we conducted a difference-in-difference (DiD) analysis and performed a crude, adjusted, and propensity score-matched analysis for each study outcome. Lastly, to observe whether there was any differential impact of the campaign across age groups, we repeated the analyses on age-stratified subgroups. Data included 5,804 survey responses, with 3,442 and 2,362 responses collected before and after the campaign, respectively. Although there was only weak evidence of increased COVID-19 vaccine confidence in the campaign-exposed group compared to the control group across all age groups, we observed a differential impact among different age groups. While no significant change was observed among young adults aged 18-24 years, the campaign exposure led to a statistically significant increase in vaccine confidence (weighted/adjusted DiD coefficient = 0.76; 95% CI: 0.06, 1.5; p-value = 0.034) and vaccination uptake (weighted/adjusted DiD coefficient = 1.69.; 95% CI: 1.02, 2.81; p-value = 0.023) among young adults aged 25-34 years. Among adults aged 35 years and above, the campaign exposure led to a significant decrease in vaccine hesitancy (weighted/adjusted DiD coefficient = -15; 95% CI: -21, -8.3; p-value<0.001). The social media campaign successfully improved vaccine hesitancy, confidence, and uptake in the Tanzanian population, albeit to varying degrees across age groups. Our study provides valuable insights for the planning and evaluation of similar social media communication campaigns aiming to bolster vaccination efforts.

PSI-5 Evaluation of EhV (surrogate for African swine fever virus) inactivation in corn- and soybean-based feed ingredients and diets at various times and temperatures during storage

Abstract African swine fever virus (ASFV) is a member of the nucleocytoplasmic large DNA viruses (NCLDVs) and remains stable in a variety of environments, including animal feed ingredients as shown in previous laboratory experiments and simulations. Emiliania huxleyi virus (EhV) is another member of NCLDV, which has a restricted host range limited to a species of marine algae called Emiliania huxleyi. This algal NCLDV has many similar morphological and physical characteristics to ASFV which makes it a safe and reliable surrogate for studying ASFV survival and inactivation in feed ingredient matrices in-situ under various time and temperature storage conditions. The objective of the present study was to investigate the inactivation of ASFV in various feedstuffs under a wide range of time and temperature conditions during storage using EhV as a surrogate. Corn- and soybean-based feed ingredients including corn, corn fermented protein, distiller dried grains with solubles, extruded soybean meal, high protein distiller’s grains, solvent-extracted soybean meal, soybean hulls, complete feed, and a positive control (no matrix) were inoculated with EhV (1 × 108 viruses/mL). Negative controls were inoculated with medium containing no EhV for each matrix. To assess the effects of different times and temperatures of storage, all samples were stored at temperatures of 4, 24, and 34 °C for 1, 5, 60, and 120 d. For each timepoint and temperature combination, samples were evaluated for virus presence (qPCR) and viability using a previously validated viability qPCR (v-qPCR) method. On average, we observed a 0.2 log reduction in viable viral DNA content over the 120-d period, with a 0.1 log reduction across varying temperatures. No reductions in EhV viability exceeding 1 log were detected for any matrix and the positive control at any time and temperature combination evaluated. No EhV was recovered from the negative control samples. Given that the experimental error was calculated to be within the range of 1 log, we concluded that storing EhV at 4, 24, or 34 °C for up to 120 d did not result in the inactivation of EhV in any of the ingredients, complete feed, or the control with no matrix. These results demonstrate that ASFV-like NCLDVs is extremely resilient and can maintain viability in various feed matrices during long-term storage and suggest that extending storage time alone may not be an effective mitigation practice against African swine fever virus.

PSI-4 Evaluation of chemical mitigants when soybean meal was inoculated with porcine epidemic diarrhea virus, porcine reproductive and respiratory virus, and Seneca Valley virus 1

Abstract Chemical mitigants have been found to decrease virus concentrations in feed and ingredient matrices. Continued research is needed to identify the appropriate inclusion levels and application time for different viruses in these matrices. Therefore, the objective was to evaluate different inclusion levels of two different chemical mitigants when applied either before or after inoculation of porcine epidemic diarrhea virus (PEDV), porcine reproductive and respiratory syndrome virus (PRRSV) and Seneca Valley virus 1 (SVV1) to soybean meal. The experiment was designed in a 2×2×2 factorial with two chemical mitigants, a formaldehyde-based product (Termin-8, Anitox Corp. Lawrenceville, GA) and a product containing Synergistic blend of phytochemicals and carboxylic acids (Finio, Anitox Corp. Lawrenceville, GA), two applications times, before virus inoculation (prevention) and after virus inoculation (mitigation), and either a low or high inclusion level (Termin-8: 2 or 3 kg/MT; Finio: 1.75 or 2.75 kg/MT). On d 1, samples of the respective matrices were weighed in 50 g aliquots and added to 500 mL bottles. Chemical mitigants were applied to the prevention samples at their respective inclusion levels and 50 µL each of 1×107 TCID50/mL PEDV, 1×108 TCID50/mL PRRSV, and 1×108 TCID50/mL SVV1 were added to the mitigation samples. All bottles were shaken and allowed to sit at room temperature for 24 h. On d 2, virus was added to the prevention samples and chemical mitigants were added to the mitigation bottles, samples incubated at room temperature for 1 h before 200 mL of phosphate buffer solution was added, and bottles incubated at 4°C for 18 h. After incubation, liquid from the samples was centrifuged and the supernatant analyzed via triplex PCR at Kansas State University Veterinary Diagnostic Laboratory. Cycle threshold and proportion PCR positive were analyzed using SAS GLIMMIX v 9.4 (SAS, Inc., Cary, NC) with each virus and matrix combination analyzed individually. A chemical mitigant×application time×inclusion level interaction was not observed (P &amp;gt; 0.05) for any virus. A chemical mitigant×application time interaction was observed (P &amp;lt; 0.05) in all three viruses, where less viral RNA was detected (P &amp;lt; 0.05) when either Termin-8 or Finio were applied after inoculation (mitigation) than when applied prior to inoculation or to the positive controls. An application time×inclusion level interaction was noticed (P &amp;lt; 0.05) for SVV1 and PEDV in soybean meal. Chemical mitigants applied at either the low or high inclusion level after inoculation (mitigation) had less detectable RNA (P &amp;lt; 0.05) than their prevention counterparts. Overall, Termin-8 and Finio can reduce detectable RNA immediately in contaminated soybean meal, with ongoing research evaluating the effect of extended contact times between the mitigants and soybean meal.

Improvements of magnetic nanoparticle assays for SARS-CoV-2 detection using a mimic virus approach

Immunoassays with magnetic nanoparticles (MNPs) as markers are a promising approach for the fast and sensitive virus detection. Upon binding of antibody-functionalized MNP on virus proteins, the hydrodynamic diameter increases and a change in the Brownian relaxation time can be measured. In this study, we detect the whole SARS-CoV-2 by mimicking it with streptavidin-coated polystyrene beads with biotinylated spike proteins. Changes of the MNP dynamics are measured by alternating current susceptometry and magnetic particle spectroscopy. Due to the multiple binding sites of MNP and virus, crosslinking enlarges the change of the hydrodynamic diameter. In order to improve the sensitivity and the limit of detection of the assay, the ratio of the virus to the MNP amount RMV/MNP is investigated in detail. High RMV/MNP ratios lead to a saturation of the MNPs with viruses, so that the cluster size and therefore the sensitivity decrease again. Additionally, it is found that the smallest virus concentrations can be detected for small MNP concentrations. It is also shown that the RMV/MNP range that can be used for an unambiguous detection of viruses depends on the virus/MNP concentration; it shifts with increasing MNP concentration to smaller RMV/MNP values. For very small virus concentrations, an increase of the Brownian relaxation time is detected implying a decrease of the hydrodynamic diameter. Furthermore, the optimal antibody concentration for MNP functionalization was determined. It is also found that a washing process with a centrifuge improves the sensitivity by reliably removing unbound antibodies and eliminating small MNPs with improper functionalization.

Navigating the Ethical Tides: The Blurred Lines of Social Media Realities

In the digital era, the rise of self-media has ushered in a torrent of information dissemination, blurring the boundaries between truth and fabrication. This article explores the challenges posed by the unchecked spread of misinformation on Chinese social media platforms. It critiques the lack of a nuanced, tiered approach in China's censorship system and advocates for a more discerning regulatory framework. Through an examination of recent events and the responsibilities of both self-media and official media, it underscores the imperative of upholding journalistic integrity and societal trust in an age dominated by viral content and fleeting clicks.

Characterization of the infectivity of an Indonesian Zika virus strain in mammalian cell lines

Objective: To characterize the infection patterns and growth characteristics of the Zika virus (ZIKV) strain JMB-185 from Indonesia in various mammalian cell lines. Methods: ZIKV was grown in human (A549, HEK293, HepG2, Huh7, Jurkat, and THP-1) and non-human mammalian (RAW264.7, Vero, and Vero76) cell lines. Viral replication kinetics were measured using plaque assay, while intra- and extracellular viral RNA concentrations were assessed using RT-PCR. Flow cytometry was used to quantify the infected cells and cell viability was measured using an MTT assay. The ability of ZIKV to infect cell lines was visualized using a fluorescence immunostaining assay. Results: This ZIKV strain preferentially infected the lung, kidney, and liver cell lines A549, HEK293, Huh7, Vero, and Vero76, but not the immune cells Jurkat, RAW264.7, and THP-1. By contrast, the ZIKV showed no sign of infection in HepG2 cells, while maintaining viral titer over 3 days post-infection, with no infection recorded in immunostaining, no increase in viral RNA, and no indication of cell deterioration. Conclusions: The Indonesian ZIKV strain has a similar infection profile as other strains, except for its poor infectivity on HepG2 cells. Information on the growth characteristics of Indonesia ZIKV will help expand our understanding of the biology of ZIKV which will be useful for various applications including antiviral discovery.

Unique immune cells in oral cavity are critical for enteric virus pathogenesis

Abstract We recently discovered that salivary glands are a major site of norovirus replication and oral-oral transmission is facilitated by saliva1. However, the cell types infected and the role of saliva in virus dissemination remains to be elucidated. Mice inoculated with norovirus were sampled and cells sorted into immune and epithelial cells. Mice became positive for virus in salivary glands and intestine plus associated lymphatic tissues. The majority of virus was present and replicating in CD45+ immune cells and EpCAM+ epithelial cells. Spatio-temporal analysis of the infection revealed that the earliest and highest viral pools were associated with the mandibular lymph nodes. Furthermore, a unique population of immune cells contained the highest concentration of virus, suggesting that these cells potentially play a sentinel role in disseminating norovirus. Notably, enteric infection of the intestine resulted in high levels of inflammation and cell death, however this was absent in the salivary glands, suggesting a level of immune modulation. Our findings suggest that the immune response in the salivary glands is different from that seen in the intestinal tract, and there is a unique population of immune cells which potentially plays an important role during the infection. 1 Ghosh S, et al. Enteric viruses replicate in salivary glands and infect through saliva. Nature. 2022; 607:345–350. doi: 10.1038/s41586-022-04895-8.