Thermal Inactivation of Hepatitis E Virus in Pork Products Estimated with a Semiquantitative Infectivity Assay.

Hepatitis E virus genotype 3 (HEV-3) is a food-borne pathogen causative of hepatitis E infections in humans. In Europe, HEV-3 is mainly transmitted through the consumption of raw or undercooked pork. In order to determine the effectiveness of control measures that can be taken in the industry or by the consumer, it is pivotal to determine the infectivity of HEV present in pork products after thermal food-processing steps.

Epidemiology of Pathogens Listed as Potential Bioterrorism Agents, the Netherlands, 2009‒2019.

We provide incidences (cases/10 million persons) in the Netherlands during 2009-2019 for pathogens listed as potential bioterrorism agents. We included pathogens from the highest categories of the European Medicines Agency or the US Centers for Disease Control and Prevention. Notifiable diseases and recently published data were used to calculate the average annual incidence.

Biosafety and biosecurity challenges during the COVID-19 pandemic and beyond.

As the world continues to battle the SARS-CoV-2 pandemic, it is a stark reminder of the devastation biological threats can cause. In an unprecedented way the global community saw a massive surge in the demand for diagnostic capacities, which had a substantial impact on biosafety and biosecurity. Laboratories had to cope with a surge in laboratory testing capacity, while resources and training possibilities were limited.

Complementarity of International Instruments in the Field of Biosecurity.

The COVID-19 pandemic has demonstrated the devastating impact of infectious disease outbreaks and the threat of emerging and re-emerging dangerous pathogens, independent of their origin. Natural, accidental, and deliberate disease outbreaks all need systems in place for an effective public health response. The best known international instrument in the field of public health is the WHO International Health Regulations (2005).

Dual-Use Quickscan: A Web-Based Tool to Assess the Dual-Use Potential of Life Science Research.

Research on pathogenic organisms is crucial for medical, biological and agricultural developments. However, biological agents as well as associated knowledge and techniques, can also be misused, for example for the development of biological weapons. Potential malicious use of well-intended research, referred to as "dual-use research", poses a threat to public health and the environment.

Systematic approach towards establishing a National Inventory of Dangerous Pathogens.

International regulations stipulate that countries need to organize their biosafety and biosecurity systems to minimize the risk of accidental (biosafety) or malicious intentional (biosecurity) release of dangerous pathogens. International Health Regulations (IHR) benchmarks from the WHO state that even for a level of limited capacity countries need to 'Identify and document human and animal health facilities that store/maintain dangerous pathogens and toxins in the relevant sectors and health professionals responsible for them'. This study provides a stepwise, systematic approach and best practices for countries to initiate a national inventory of dangerous pathogens.

Surface chemistry-dependent antiviral activity of silver nanoparticles.

The toxicity towards viruses of silver nanoparticles (AgNPs) has been reported to be dependent on several factors such as particle concentration, size, and shape. Although these factors may indeed contribute to the toxicity of AgNPs, the results presented in this work demonstrate that surface chemistry and especially surface charge is a crucial factor governing their antiviral activity. Here, this work investigated the influence of capping agents representing various surface charges ranging from negative to positive.

The Vulnerability Scan, a Web Tool to Increase Institutional Biosecurity Resilience.

The importance of vigilance within organizations working with high-risk biological material receives increasing attention. However, an in-depth and comprehensive tool, dedicated to increase awareness of potential risks and to assess an organization's current biosecurity vulnerabilities, has not been available yet. We developed the "Biosecurity Vulnerability Scan," a web tool that identifies biosecurity gaps in an organization based on eight biosecurity pillars of good practice.

Norovirus Outbreak Associated with Swimming in a Recreational Lake Not Influenced by External Human Fecal Sources in The Netherlands, August 2012.

Swimming in fecally contaminated recreational water may lead to gastrointestinal illness. A recreational water-associated outbreak of norovirus (NoV) infections affecting at least 100 people in The Netherlands occurred in August 2012. Questionnaire responses from patients indicated swimming in recreational lake Zeumeren as the most likely cause of illness.

Quantitative farm-to-fork risk assessment model for norovirus and hepatitis A virus in European leafy green vegetable and berry fruit supply chains.

Fresh produce that is contaminated with viruses may lead to infection and viral gastroenteritis or hepatitis when consumed raw. It is thus important to reduce virus numbers on these foods. Prevention of virus contamination in fresh produce production and processing may be more effective than treatment, as sufficient virus removal or inactivation by post-harvest treatment requires high doses that may adversely affect food quality.

Virus transfer proportions between gloved fingertips, soft berries, and lettuce, and associated health risks.

Multiple outbreaks of human norovirus (hNoV) have been associated with fresh produce, such as soft berries and lettuce. Even though food handlers are considered an important source for the introduction of hNoV into food chains, their contribution to public health risks associated with hNoV remains unknown. To assess to which extent food handlers contribute to the introduction and spread of hNoV in fresh produce chains quantitative virus transfer data are needed.

Aichi virus in sewage and surface water, the Netherlands.

Detection of Aichi virus in humans was initially reported in Japan in 1989. To establish a timeline for the prevalence of Aichi virus infection among humans in the Netherlands, we conducted molecular analysis of archival water samples from 1987-2000 and 2009-2012. Aichi virus RNA was detected in 100% (8/8) of sewage samples and 100% (7/7) of surface water samples collected during 1987-2000 and 100% (8/8) of sewage samples and 71% (5/7) of surface water samples collected during 2009-2012.

Persistence of human norovirus in reconstituted pesticides--pesticide application as a possible source of viruses in fresh produce chains.

The consumption of fresh produce is frequently associated with outbreaks of human norovirus (hNoV) disease. To prevent the contamination of fresh produce with hNoV, knowledge of the possible introduction sources of the viruses, such as water, is needed to be able to implement appropriate and efficient preventive measures. Contaminated water used to reconstitute pesticides could be a relevant source of infectious hNoV, determined by the initial level of virus contamination and the persistence of these viruses in reconstituted pesticides.

Persistence of human norovirus GII.4 and GI.4, murine norovirus, and human adenovirus on soft berries as compared with PBS at commonly applied storage conditions.

Human noroviruses (hNoV) have been detected on soft fruits. Especially raspberries have been found to be associated with outbreaks of gastroenteritis suggesting persistence of hNoV on these fruits. Therefore, the persistence of hNoV GII.

QMRAspot: a tool for Quantitative Microbial Risk Assessment from surface water to potable water.

In the Netherlands, a health based target for microbially safe drinking water is set at less than one infection per 10,000 persons per year. For the assessment of the microbial safety of drinking water, Dutch drinking water suppliers must conduct a Quantitative Microbial Risk Assessment (QMRA) at least every three years for the so-called index pathogens enterovirus, Campylobacter, Cryptosporidium and Giardia. In order to collect raw data in the proper format and to automate the process of QMRA, an interactive user-friendly computational tool, QMRAspot, was developed to analyze and conduct QMRA for drinking water produced from surface water.

Pathogenic Vibrio species in dutch shellfish destined for direct human consumption.

Vibrio parahaemolyticus is a common cause of shellfish-related gastroenteritis all over the world. V. parahaemolyticus and Vibrio alginolyticus have previously been detected in water samples from the Oosterschelde, a large inlet on the North Sea, which is used for both recreational purposes and shellfish production.

Sources of hepatitis E virus genotype 3 in The Netherlands.

Non-travel-related hepatitis E virus (HEV) genotype 3 infections in persons in the Netherlands may have a zoonotic, foodborne, or water-borne origin. Possible reservoirs for HEV transmission by water, food, and animals were studied. HEV genotype 3/open reading frame 2 sequences were detected in 53% of pig farms, 4% of wild boar feces, and 17% of surface water samples.

The course of hepatitis E virus infection in pigs after contact-infection and intravenous inoculation.

Background: Worldwide, hepatitis E virus (HEV) genotype 3 is observed in pigs and transmission to humans is implied. To be able to estimate public health risks from e.g.

Estimation of hepatitis E virus transmission among pigs due to contact-exposure.

Locally acquired hepatitis E in humans from industrialized countries has been repeatedly suggested to originate from pigs. Pigs may serve as a reservoir of hepatitis E virus (HEV) for humans when a typical infected pig causes on average more than one newly infected pig, a property that is expressed by the basic reproduction ratio R(0). In this study, R(0) for HEV transmission among pigs was estimated from chains of one-to-one transmission experiments in two blocks of five chains each.

Hepatitis E virus RNA in commercial porcine livers in The Netherlands.

Human hepatitis E virus (HEV) infections by genotype 3 strains in industrialized countries are hypothesized to be caused by pigs. To examine this hypothesis, the potential health risks of transmission routes should be examined. Possible foodborne transmission was studied by quantifying the presence and infectivity of HEV in commercial porcine livers in The Netherlands.

Rapid virus detection procedure for molecular tracing of shellfish associated with disease outbreaks.

Detection of pathogenic viruses in oysters implicated in gastroenteritis outbreaks is often hampered by time-consuming, specialist virus extraction methods. Five virus RNA extraction methods were evaluated with respect to performance characteristics and sensitivity on artificially contaminated oyster digestive glands. The two most promising procedures were further evaluated on bioaccumulated and naturally contaminated oysters.

Increased hepatitis E virus prevalence on Dutch pig farms from 33 to 55% by using appropriate internal quality controls for RT-PCR.

Pigs have been suggested to be a potential reservoir for locally acquired human hepatitis E virus (HEV) infections in the Netherlands. To study possible trends in HEV prevalence in the Dutch pig population, 97 pig farms have been screened for the presence of HEV in stools. The prevalence rate of HEV was estimated at 55% (53/97) in 2005, indicating a significant increase as compared to the prevalence rate of 22% (25/115) as was reported in 1999.

Detection of noroviruses in foods: a study on virus extraction procedures in foods implicated in outbreaks of human gastroenteritis.

Disease outbreaks in which foods are epidemiologically implicated as the common source are frequently reported. Noroviruses and enteric hepatitis A viruses are among the most prevalent causative agents of foodborne diseases. However, the detection of these viruses in foods other than shellfish is often time-consuming and unsuccessful.

Real-time detection of noroviruses in surface water by use of a broadly reactive nucleic acid sequence-based amplification assay.

Noroviruses are the most common agents causing outbreaks of viral gastroenteritis. Outbreaks originating from contaminated drinking water and from recreational waters have been described. Due to a lack of cell culture systems, noroviruses are detected mostly by molecular methods.