Hepatitis A infections from food

Whole-Genome Sequencing-Based Confirmatory Methods on RT-qPCR Results for the Detection of Foodborne Viruses in Frozen Berries

Accurate detection, identification, and subsequent confirmation of pathogens causing foodborne illness are essential for the prevention and investigation of foodborne outbreaks. This is particularly true when the causative agent is an enteric virus that has a very low infectious dose and is likely to be present at or near the limit of detection. In this study, whole-genome sequencing (WGS) was combined with either of two non-targeted pre-amplification methods (SPIA and SISPA) to investigate their utility as a confirmatory method for RT-qPCR positive results of foods contaminated with enteric viruses. Frozen berries (raspberries, strawberries, and blackberries) were chosen as the food matrix of interest due to their association with numerous outbreaks of foodborne illness. The hepatitis A virus (HAV) and human norovirus (HuNoV) were used as the contaminating agents. The non-targeted WGS strategy employed in this study could detect and confirm HuNoV and HAV at genomic copy numbers in the single digit range, and in a few cases, identified viruses present in samples that had been found negative by RT-qPCR analyses. However, some RT-qPCR-positive samples could not be confirmed using the WGS method, and in cases with very high Ct values, only a few viral reads and short sequences were recovered from the samples. WGS techniques show great potential for confirmation and identification of virally contaminated food items. The approaches described here should be further optimized for routine application to confirm the viral contamination in berries.

Current perspectives of viral hepatitis

Viral hepatitis represents a major danger to public health, and is a globally leading cause of death. The five liver-specific viruses: Hepatitis A virus, hepatitis B virus, hepatitis C virus, hepatitis D virus, and hepatitis E virus, each have their own unique epidemiology, structural biology, transmission, endemic patterns, risk of liver complications, and response to antiviral therapies. There remain few options for treatment, in spite of the increasing prevalence of viral-hepatitis-caused liver disease. Furthermore, chronic viral hepatitis is a leading worldwide cause of both liver-related morbidity and mortality, even though effective treatments are available that could reduce or prevent most patients' complications. In 2016, the World Health Organization released its plan to eliminate viral hepatitis as a public health threat by the year 2030, along with a discussion of current gaps and prospects for both regional and global eradication of viral hepatitis. Today, treatment is sufficiently able to prevent the disease from reaching advanced phases. However, future therapies must be extremely safe, and should ideally limit the period of treatment necessary. A better understanding of pathogenesis will prove beneficial in the development of potential treatment strategies targeting infections by viral hepatitis. This review aims to summarize the current state of knowledge on each type of viral hepatitis, together with major innovations.

Global outbreaks of foodborne hepatitis A: Systematic review and meta-analysis

Hepatitis A Virus (HAV) is a significant threat in terms of food safety. A systematic literature search with the research question "What are the clinical outcomes of foodborne Hepatitis A virus infections?" was conducted. The pooled estimate of the outcomes-mortality, hospitalization, and severity rates, along with a 95% confidence interval (CI), was estimated. After screening, 33 studies were included for the data extraction and meta-analysis. The pooled prevalence of hospitalization among the HAV-positive patients was estimated to be 32% (95% CI 21-44), with high heterogeneity (I2 = 98%, p < 0.01). Australia had the highest hospitalization rate, with 82%, followed by Europe (42%). The hospitalization rate showed a significantly increasing trend (beta = 0.015, p=0.002) over the period. The pooled prevalence of mortality among the HAV-positive patients was estimated to be <1%, with low heterogeneity (I2 = 5%, p = 0.39). A wide range of food products were linked with the HAV outbreaks.

Common and Potential Emerging Foodborne Viruses: A Comprehensive Review

Human viruses and viruses from animals can cause illnesses in humans after the consumption of contaminated food or water. Contamination may occur during preparation by infected food handlers, during food production because of unsuitably controlled working conditions, or following the consumption of animal-based foods contaminated by a zoonotic virus. This review discussed the recent information available on the general and clinical characteristics of viruses, viral foodborne outbreaks and control strategies to prevent the viral contamination of food products and water. Viruses are responsible for the greatest number of illnesses from outbreaks caused by food, and risk assessment experts regard them as a high food safety priority. This concern is well founded, since a significant increase in viral foodborne outbreaks has occurred over the past 20 years. Norovirus, hepatitis A and E viruses, rotavirus, astrovirus, adenovirus, and sapovirus are the major common viruses associated with water or foodborne illness outbreaks. It is also suspected that many human viruses including Aichi virus, Nipah virus, tick-borne encephalitis virus, H5N1 avian influenza viruses, and coronaviruses (SARS-CoV-1, SARS-CoV-2 and MERS-CoV) also have the potential to be transmitted via food products. It is evident that the adoption of strict hygienic food processing measures from farm to table is required to prevent viruses from contaminating our food.

Synergistic effects of sequential treatment using disinfectant and e-beam for inactivation of hepatitis a virus on fresh vegetables

Hepatitis A virus (HAV) has adversely affected public health worldwide, causing an economic burden on many countries. Fresh vegetables are reported as a source of HAV infections during production, harvesting, and distribution, which cause the emergence of foodborne illnesses. Therefore, in this study, the synergistic effects of chemical (sodium hypochlorite [NaOCl] and chlorine dioxide [ClO2]) and physical (electron-beam [e-beam] irradiation) sequential treatment for HAV inactivation on fresh vegetables were investigated, and the physicochemical quality changes of vegetables were evaluated after each treatment. On bell pepper and cucumber sequentially treated with NaOCl (50-500 ppm) and e-beam (1-5 kGy), the HAV titer was reduced by 0.19-4.69 and 0.28-4.78 log10 TCID50/mL, respectively. Sequential treatment with ClO2 (10-250 ppm) and e-beam (1-5 kGy) reduced the HAV titer on bell pepper and cucumber by 0.41-4.78 and 0.26-4.80 log10 TCID50/mL, respectively. The sequential treatments steadily decreased the HAV titers on each food by a significant difference (p < 0.05) compared to the controls. The treatment combinations of 500 ppm NaOCl and 3 kGy (e-beam) on bell pepper and 150 ppm NaOCl and 1 kGy (e-beam) on cucumber provided maximum synergistic effects. It was also found that sequential treatment with 50 ppm ClO2 and 5 kGy (e-beam) on bell pepper and 10 ppm ClO2 and 5 kGy (e-beam) on cucumber most efficiently inactivated HAV. Additionally, bell pepper and cucumber showed no significant quality changes (p < 0.05) after the treatment. Therefore, the sequential treatment with NaOCl or ClO2 and e-beam is expected to effectively control HAV on fresh vegetables without changing the food quality compared to either treatment alone.

Hepatitis a Vaccine as Opportunity of Primary Prevention for Food Handlers: A Narrative Review

The hepatitis A virus (HAV) is still a leading cause of viral hepatitis worldwide. After a long incubation period, the clinical manifestations range from asymptomatic infection to acute liver failure. The severity of the disease increases with age and pre-existing liver disease. The transmission is mainly via person-to-person contact or ingestion of contaminated food or water. Food contamination can occur at any step of the food chain, especially when infected people handle not-heated or otherwise-treated food. HAV is endemic in low-income countries because of poor sanitary and sociodemographic conditions. The populations of developed countries are highly susceptible, and large outbreaks occur when HAV is introduced from endemic countries due to globalization, travel, and movement of foodstuffs. HAV prevention includes hygiene practices, immunoglobulins, and vaccination. Safe and effective inactivated and live attenuated vaccines are available and provide long-term protection. The vaccine targets are children and subjects at increased risk of HAV exposure or serious clinical outcomes. This review discusses the critical role of food handlers in the spread of HAV and the opportunity for food industry employers to consider food handler immunization a tool to manage both food safety in compliance with HACCP principles and food operators' biologic risk.

Hepatitis A virus outbreak in Lebanon: Is it a matter of concern?

Lebanon has been grappling with hepatitis A virus (HAV) outbreaks for 3 decades, to an extent that it has been now termed an endemic zone for HAV. However, the rise in cases above the annual average concerns a potential outbreak in the North, and the Bekaa governorates of Lebanon must be highlighted. Although the Lebanese health authorities have ordered a probe into the possible causes of the outbreak, it has been speculated that the immigration of Syrian refugees has overburdened public health services. Reduced seroprevalence of HAV immunoglobulin G has also led to an epidemiological shift from child to adult populations. The current economic crisis affecting Lebanese society is another significant problem that could have contributed to the rise in incidents. This article examines Lebanon's current HAV outbreak and epidemiological status, offering suggestions for the future. In the event of an outbreak, the infrastructure for water sanitation and sewage is known to allow HAV to spread via the faecal-oral pathway. Maintaining personal hygiene, early detection, and vaccination have all been recommended as significant regional and individual control measures.

Antibacterial, Antifungal and Antiviral Polymeric Food Packaging in Post-COVID-19 Era

Consumers are now more concerned about food safety and hygiene following the COVID-19 pandemic. Antimicrobial packaging has attracted increased interest by reducing contamination of food surfaces to deliver quality and safe food while maintaining shelf life. Active packaging materials to reduce contamination or inhibit viral activity in packaged foods and on packaging surfaces are mostly prepared using solvent casting, but very few materials demonstrate antiviral activity on foods of animal origin, which are important in the human diet. Incorporation of silver nanoparticles, essential oils and natural plant extracts as antimicrobial agents in/on polymeric matrices provides improved antifungal, antibacterial and antiviral properties. This paper reviews recent developments in antifungal, antibacterial and antiviral packaging incorporating natural or synthetic compounds using preparation methods including extrusion, solvent casting and surface modification treatment for surface coating and their applications in several foods (i.e., bakery products, fruits and vegetables, meat and meat products, fish and seafood and milk and dairy foods). Findings showed that antimicrobial material as films, coated films, coating and pouches exhibited efficient antimicrobial activity in vitro but lower activity in real food systems. Antimicrobial activity depends on (i) polar or non-polar food components, (ii) interactions between antimicrobial compounds and the polymer materials and (iii) interactions between environmental conditions and active films (i.e., relative humidity, oxygen and water vapor permeability and temperature) that impact the migration or diffusion of active compounds in foods. Knowledge gained from the plethora of existing studies on antimicrobial polymers can be effectively utilized to develop multifunctional antimicrobial materials that can protect food products and packaging surfaces from SARS-CoV-2 contamination.

A 2019 Outbreak Investigation of Hepatitis A Virus Infections in the United States Linked to Imported Fresh Blackberries

Globally, hepatitis A virus (HAV) is one of the most common agents of acute viral hepatitis and causes approximately 1.4 million cases and 90,000 deaths annually despite the existence of an effective vaccine. In 2019, federal, state, and local partners investigated a multi-state outbreak of HAV infections linked to fresh blackberries sourced from multiple suppliers in Michoacán, Mexico. A total of 20 individuals with outbreak-related HAV infection were reported in seven states, including 11 hospitalizations, and no deaths. The Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and Nebraska State and Douglas County Health Departments conducted a traceback investigation for fresh blackberries reportedly purchased by 16 ill persons. These individuals reported purchasing fresh blackberries from 11 points of service from September 16 through 29, 2019 and their clinical isolates assessed through next-generation sequencing and phylogenetic analysis were genetically similar. The traceback investigation did not reveal convergence on a common grower or packing house within Mexico, but all of the blackberries were harvested from growers in Michoacán, Mexico. FDA did not detect the pathogen after analyzing fresh blackberry samples from four distributors, one consumer, and from nine importers at the port of entry as a result of increased screening. Challenges included gaps in traceability practices and the inability to recover the pathogen from sample testing, which prohibited investigators from determining the source of the implicated blackberries. This multi-state outbreak illustrated the importance of food safety practices for fresh produce that may contribute to foodborne illness outbreaks.

Crystal digital RT-PCR for the detection and quantification of norovirus and hepatitis A virus RNA in frozen raspberries

Berries are important vehicles for norovirus (NoV) and hepatitis A virus (HAV) foodborne outbreaks. Sensitive and quantitative detection of these viruses in food samples currently relies on RT-qPCR, but remains challenging due to their low concentration and the presence of RT-qPCR inhibitors. Moreover, quantification requires a standard curve. In this study, crystal digital RT-PCR (RT-cdPCR) assays were adapted from RT-qPCR sets of primers and probe currently used in our diagnostic laboratory for the detection and precise quantification of norovirus genogroups I and II (NoV GI, GII) and hepatitis A virus (HAV) RNA in frozen raspberry samples. We selected assay conditions based on optimal separation of positive and negative droplets, and peak resolution. Using virus-specific in vitro RNA transcripts diluted in raspberry RNA extracts, we showed that all three RT-cdPCR assays were sensitive, and we estimated the 95 % detection limit at 9 copies per RT-cdPCR reaction for NoV GI, 3 for NoV GII, and 14 for HAV. Serial dilutions of the RNA transcripts showed excellent linearity over a range of four orders of magnitude. We achieved precise quantification (CV ≤ 35 %) of the RNA transcripts between runs down to 15-145 copies per reaction for NoV GI, <20 for NoV GII, and < 15 for HAV. The three RT-cdPCR assays also proved to be tolerant to inhibitors from frozen raspberries, although not as tolerant as the RT-qPCR assays in the case of NoV GI and HAV. We further evaluated the assays with inoculated frozen raspberry samples and compared their performance to that of the RT-qPCR assays. As compared to the corresponding RT-qPCR assays, the NoV GI and HAV RT-cdPCR assays showed a decreased qualitative sensitivity, while the NoV GII RT-cdPCR assay had an increased sensitivity. As for quantification, the NoV GI and NoV GII RT-cdPCR assays produced similar estimates of RNA copy number than their respective RT-qPCR assays, whereas for HAV, the RT-cdPCR assay produced lower estimates than the RT-qPCR assay. However, all the RT-cdPCR assays provided more precise quantitative measurements at low levels of contamination than the RT-qPCR assays. In conclusion, the potential of the RT-cdPCR assays in this study to detect viral RNA from frozen raspberries varied according to assay, but these RT-cdPCR assays should be considered for precise absolute quantification in difficult matrices such as frozen raspberries.

Analysis of Cytochrome c Expression on Liver Histology of Hepatitis Rats after Administration of Tin and Olive Leaf Ethanol Extract

<b>Background and Objective:</b> Hepatitis is a liver illness caused by a viral infection, autoimmune conditions or the use of certain medicines. In molecular hepatitis treatment, cytochrome c can be used as a potential predictor of the severity of liver impairment. In Asia, particularly in Indonesia, antioxidant-rich plants include <i>Ficus</i> <i>carica</i> and <i>Olea europaea.</i> This study aimed to see what impact cytochrome c in hepatitis after these two botanicals were administered. <b>Materials and Methods:</b> Rats were grouped as follows: Normal rats with no additions or herbs (G₀), the physiological solution group (G₁), the intravenous administration of the quercetin-copper (II) (G₂), Olive leaf extract or OLE (300 mg kg¹ b.wt.) (G₃) and Tin leaf extract or TLE (100 mg kg¹ b.wt.) (G₄). For an animal model of hepatitis, the rats were given thioacetamide 280 mg kg¹ b.wt., 8 days later. The rats were dissected and blood and liver samples were collected for enzyme and immunohistochemistry examination. <b>Results:</b> Malondialdehyde (MDA), superoxide dismutase (SOD) and cytochrome c expression levels differed significantly (p<0.05) across treatment groups in rat's models of hepatitis. Hepatocytes first displayed symptoms of lipid degradation, inflammatory and necrosis cells. When administered quercetin and the two herbs, necrosis and inflammatory cells were reduced, demonstrating that OLE and TLE can enhance liver histology and lower cytochrome c expression in a mouse model of hepatitis. <b>Conclusion:</b> Administration of Olive leaf extract (OLE) and Tin leaf extract (TLE) can improve liver histology in hepatitis model rats while decreasing cytochrome c expression, which is a mechanism for hepatocyte cell death.

Food Safety and Employee Health Implications of COVID-19: A Review

The COVID-19 pandemic has greatly impacted the U.S. food supply and consumer behavior. Food production and processing are being disrupted as illnesses, proactive quarantines, and government-mandated movement restrictions cause labor shortages. In this environment, the food industry has been required to adopt new, additional practices to minimize the risk of COVID-19 cases and outbreaks among its workforce. Successfully overcoming these challenges requires a comprehensive approach that addresses COVID-19 transmission both within and outside the facility. Possible interventions include strategies (i) to vaccinate employees, (ii) to assure that employees practice social distancing, (iii) to assure that employees wear face coverings, (iv) to screen employees for COVID-19, (v) to assure that employees practice frequent hand washing and avoid touching their faces, (vi) to clean frequently touched surfaces, and (vii) to assure proper ventilation. Compliance with these control strategies must be verified, and an overall COVID-19 control culture must be established to implement an effective program. Despite some public misperceptions about the health risk of severe acute respiratory syndrome coronavirus 2 on foods or food packaging, both the virus biology and epidemiological data clearly support a negligible risk of COVID-19 transmission through food and food packing. However, COVID-19 pandemic-related supply chain and workforce disruptions and the shift in resources to protect food industry employees from COVID-19 may increase the actual food safety risks. The goal of this review was to describe the COVID-19 mitigation practices adopted by the food industry and the potential impact of these practices and COVID-19-related disruptions on the industry's food safety mission. A review of these impacts is necessary to ensure that the food industry is prepared to maintain a safe and nutritious food supply in the face of future global disruptions.

Determinants of hepatitis A infection among students: A case study of an outbreak in Jember, Indonesia

BACKGROUND

Hepatitis A often occurs in school among students in the form of an outbreak. The transmission was through fecal-oral (Common Source) provided that the epidemic curve is close to propagated. The aim of the current study was to analyze the determinants of Hepatitis A Infection among students. Design and methods: This study was a case-control study which was conducted at SMAN Plus with a sample size of 80 students chosen by using simple random sampling. The data obtained were then analyzed using logistic regression with 95% confidence level (α = 0.05), while the strength of the relationship between variables was identified using Odds Ratio (OR).

RESULTS

 Most of the students were at the age of 17 to 19 years old (65%) and male (57.5%). The average age in the case group was 17.1 years old, while in the control group was 16.75 years old. The habit of consuming raw foods (p = 0.001) as well as eating and drink at the same time during an activity (p = 0.000) had a significant influence on the outbreak of Hepatitis A in the curve epidemic of common source.

CONCLUSIONS

 The outbreak is confirmed as a transmission occurs through fecal-oral which the common source epidemic curve. Risk factors that have been proven to be related to Hepatitis A include consuming raw food, eating shared meals during an activity, and drinking with shared drinking utensils.

Predictors of hepatitis A immunity in adults in California in order to better utilize hepatitis A vaccine

BACKGROUND

Hepatitis A vaccine recommendations now include homelessness, illegal drug use, and HIV, as well as traditional risk factors and travel to areas endemic for hepatitis A. We examined a large diverse population for predictors of Hepatitis A immunity in order to better utilize Hepatitis A vaccine.

METHODS

We performed a cross-sectional descriptive study of members of a large integrated health plan with a test for Hepatitis A Immunoglobulin G (IgG) between January 1st, 2007, and December 31st, 2017. Exclusion criteria included age <18 years, <6 months of continuous enrollment, and Hepatitis A vaccine prior to Hepatitis A test. Variables of interest were age, gender, primary language spoken, ethnicity/race, neighborhood household income, and history of travel or history of jaundice. Multivariable logistic regression was performed to evaluate the association of risk factors on Hepatitis A immunity.

RESULTS

Of the 318,170 persons ≥ 18 years tested for Hepatitis A immunity, 155, 842 persons had a reactive Hepatitis A IgG test (49%). The lowest prevalence was for Whites at 28.1% followed by Blacks at 35.8%. Hispanics and Asian/Pacific Islanders had prevalence rates of 63% and 68.2% respectively. In adjusted analyses, Asian/Pacific Islanders, Hispanics and Blacks were 5.17, 3.44 and 1.42 times more likely to have Hepatitis A immunity than Whites. Those that spoke Spanish or language other than English or Spanish as their primary preferred language were 6.11 and 3.27 time more likely to have immunity than English speakers. Known travel history conferred a 2.16 likelihood of Hepatitis A immunity.

CONCLUSIONS

Persons of Hispanic and Asian/Pacific Islander background as well as persons with a preferred spoken language other than English have a high prevalence of Hepatitis A immunity. Testing for Hepatitis A immunity prior to vaccination should be considered for these groups.

Occurrence and Accumulation of Human Enteric Viruses and Phages in Process Water from the Fresh Produce Industry

The virological quality of process water (PW) used by the produce industry has received limited attention. As a first step to overcoming technical limitations in monitoring viruses in PW, the analytical performance of ultrafiltration was assessed to concentrate viral particles from 20 L of spiked PW. The selected method used for sample concentration of PW was carefully validated, thus enabling the accurate quantification and estimation of viral titers of human enteric viruses and phages. PW from the produce industry was collected periodically from the washing tanks of commercial facilities. The analysis of coliphages was performed by plaque assay, while the occurrence of enteric viruses and crAssphage was determined by molecular techniques. Significant differences in the physicochemical composition of PW, mostly due to the different nature of fresh produce types and differences in the sanitizer used in commercial operation, were observed. Accumulation of crAssphage and coliphages was observed in PW, but correlation with human enteric viruses was not possible due to the low prevalence of these pathogens in the PW analyzed. The obtained results showed that depending on the type of product washed, the product/water ratio and the residual concentrations of the sanitizers, the prevalence and concentration of bacteriophages changed significantly.

Endemicity change of hepatitis A infection necessitates vaccination in food handlers: An Indian perspective

In the last two decades, outbreaks due to the foodborne hepatitis A virus (HAV) have been frequently reported in India, with adolescents and adults primarily affected. In India, most food handlers are adolescents and young adults who might be exposed to unsatisfactory environmental conditions and poor water quality. This increases the risk of HAV infection and consequently compounds the risk of HAV transmission from food handlers to susceptible populations. Given the shift in hepatitis A endemicity from high to intermediate levels in India, implementing the vaccination of food handlers has become important as it can also contribute to the elimination of hepatitis A in India. This narrative review makes a case for hepatitis A immunization of food handlers in India considering the growing food industry, evolving food culture, and the substantial burden caused by hepatitis A outbreaks.

What is the context?

Hepatitis A disease is a common form of viral hepatitis and is transmitted through contaminated food and water or through close contact with an infected person. The virus with stands high temperature and can survive on surfaces for long periods of time.

In India, the burden of hepatitis A has shifted from children to adolescents and adults who are more culnerable to infection. They present a high risk of complications, often requiring hopitalization.

The prevention of the disease has often bee neglected, inadequate safety measures for the preparation of food (via food handlers) is a known risk factor for the transmission of hepatitis A.

What is new?

Our review highlights the relationship between food handling and hepatitis A infection among adolescents and adults in Inida.

The lack of knowledge of food safety regulations and hygiene measures among food handlers and the organizations that guide them may contribute to the spread of hepatitis A.

What is the impact?

Sanitation efforts, awareness and educational programs for food are needed to help reduce the transmission of hepatitis A virus and disease, yet these measures alone may not be sufficient.

Vaccination among high-risk populations such as food handlers can prevent hepatitis A infection and its complications as well as transmission.

Persistence of Hepatitis A Virus RNA in Water, on Non-porous Surfaces, and on Blueberries

Enteric viruses, such as human norovirus and hepatitis A virus (HAV), are the leading cause of transmissible foodborne illness. Fresh produce such as berries are often contaminated by infected food handlers, soiled water, or food contact surfaces. The gold-standard method for virus detection throughout the food chain is RT-qPCR, which detects portions of genomes including non-infectious viral particles and naked viral RNA. The aim of this study was to evaluate the persistence of heat-inactivated HAV in water, phosphate-buffered saline, on stainless steel and polyvinyl chloride, and on blueberries at −80°C, −20°C, 4°C, and room temperature. In water and phosphate-buffered saline, viral RNA could be detected for up to 90 days regardless of temperature when the initial load was 2.5 × 10⁴ or 2.5 × 10⁶ genome copies. It was detected on polyvinyl chloride and blueberries under most conditions. On stainless steel, the large initial load persisted for 90 days, while the medium-level load was detected only up to 16 days at room temperature or 60 days at 4°C. The detection of non-infectious viral RNA can confound investigations of gastroenteritis outbreaks. Pretreatments that discriminate between naked RNA, non-infectious virions and infectious virions need to be included in the RT-qPCR method in order to reduce the risk of positive results associated with non-infectious viral particles.