Hepatitis A: Epidemiology, High-Risk Groups, Prevention and Research on Antiviral Treatment

Hepatitis A vaccination in a racially and sexually diverse population of gay, bisexual, and other men who have sex with men: Findings from the QVax study

BACKGROUND

Previous studies found vaccination uptake of vaccine-preventable diseases (VPD) to be associated with race/ethnicity and medical mistrust among key populations, however, few studies examine Hepatitis A vaccination uptake.

METHODS

This cross-sectional study used online survey data collected from NJ and NY residents identifying as lesbian, gay, bisexual, transgender, queer (LGBTQ+) from October 2021 through November 2022.

RESULTS

This study used a subsample of 222 gay, bisexual, and other cisgender men, 66.7% White, with mean age 41.22 years (SD = 15.23), and 60% fully vaccinated for Hepatitis A. Overall, average group-based medical mistrust scores did not differ among non-vaccinated participants compared to fully or partially vaccinated participants. However, higher group-based medical mistrust scores were associated with non-White identifying participants, and were highest among Hispanic/Latinx (2.68, sd = 0.43) and Black non-Hispanic (2.58, sd = 0.50) participants (p < .001). Vaccination patterns did not differ among fear or vaccine confidence-based items.

CONCLUSIONS

Our results contribute to the limited knowledge of differences in Hepatitis A vaccination uptake among men who have sex with men, and support the need for targeted intervention programs that acknowledge the diverse population of LGBTQ + identifying individuals and their associated health behaviors.

Exploring hepatitis A dynamics in Israel, 2019-2022

BACKGROUND

Continuous monitoring of Hepatitis A Virus (HAV) may assist in identifying local outbreaks. The advent of the COVID-19 pandemic, which affected the circulation of numerous pathogens, may have also impacted the scope of HAV infections.

AIM

To investigate the incidence and environmental dissemination of HAV between 2019 and 2022 in Israel, a country with an anti-HAV vaccination program.

METHODS

HAV RT-PCR analysis was performed for all HAV cases and for 280 sewage samples collected in 2019-2022. Available amplified HAV fragments from clinical (n = 107) and sewage (n = 27) were also assessed by genotyping and phylogenetic analysis.

RESULTS

In 2019-2022, 158 individuals and 12.9 % (36/280) of sewage samples were HAV-RNA positive. Median age was 30 years (IQR 20.5-44); approximately half (51.9 %, 82/158) were males. Almost all patients (98.4 %, 124/126) were not vaccinated. Highest numbers were identified in 2019 (84 cases and 30 %, 21/71, positive sewage samples). In 2020, when three COVID-19 related lockdowns were implemented, 24 cases and 4.3 % (3/69) sewage samples were HAV-RNA positive. The number of HAV-RNA positive cases and positive sewage samples remained low in 2021-2022 (31 and 19 cases, 13.2 %, 9/68 and 4.2 %, 3/72 positive sewage samples, respectively). Sub-genotype IB dominated (90.7 %, 97/107 of cases and 81.5 %, 22/27 of sewage samples), and phylogenetic analysis of HAV samples demonstrated small transmission clusters of sequences from Jews, Bedouin Arabs and foreign workers. Sub-genotype IA was identified in 8.4 % (9/107) of cases and in 18.5 % (5/27) of sewage samples.

CONCLUSION

Combined clinical and environmental surveillance is optimal for monitoring HAV. In 2020, the circulation of HAV decreased, possibly following COVD-19 health restrictions. In subsequent years, the incidence remained low. Adults in risk-groups for HAV infection should be vaccinated to minimize HAV circulation.

Prevention and management of infectious and tropical diseases in kidney transplant recipients residing in European outermost and overseas territories

BACKGROUND

The European Union encompasses 30 outermost and overseas countries and territories (OCTs). Despite a recent increasing activity of renal transplantation in these territories, many patients still undergo transplantation in continental Europe, with follow-up care coordinated between health professionals from both their transplant center and their home region. Each territory has its unique infectious epidemiology which must be known to ensure appropriate care for kidney transplant recipients (KTRs).

AIMS

This paper proposes a pragmatic approach to optimize pre-transplant check-up and to provide an overview of the specific epidemiological features of each region. It offers practical algorithms to help practitioners in managing infected KTR living in these territories. This work advocates for increased collaborative research among European OCTs.

Advances in the Elimination of Viral Hepatitis in Mexico: A Local Perspective on the Global Initiative

Viral hepatitis (A-E) presents a major global health challenge. In 2015, the World Health Organization (WHO) launched an initiative to eliminate viral hepatitis, with the aim of reducing new infections by 90% and deaths by 65% by 2030. Mexico is one of 38 focus countries identified by the WHO, collectively accounting for 80% of global infections and deaths. While hepatitis B and C are commonly diagnosed in Mexico, routine diagnosis for hepatitis D and E is lacking, with no specific epidemiological data available. In 2020, Mexico implemented the National Hepatitis C Elimination Program, focusing on preventing new infections, reducing complications like cirrhosis and hepatocellular carcinoma, ensuring access to treatment, and improving patient care. However, this program has not been extended to hepatitis B and E. Addressing the challenges of viral hepatitis control in Mexico requires increased resource allocation, expanded diagnosis, vaccination for hepatitis A and B, and treatment coverage for hepatitis B and C, along with multisectoral engagement. This work provides an overview of Mexico's response to the global initiative, highlighting its progress, challenges, and areas of opportunity.

Use of passive samplers as sewage surveillance tool to monitor a hepatitis A outbreak at a school in Amsterdam, the Netherlands, Oct 2022 - March 2023

BACKGROUND

Enteric hepatitis A virus (HAV) infections during childhood are often asymptomatic but may cause severe illness in adults. To improve public health surveillance we assessed the applicability of sewage monitoring during an HAV outbreak at a primary school.

METHODS

Between October 19 and December 27, 2022, five symptomatic HAV cases were notified to the Public Health Service Amsterdam; all attended the same primary school. Passive samplers, small absorbent tools, were deployed in sewage near the school from November 14, 2022, to March 22, 2023. The absorbents were subjected to RNA extraction, HAV PCR testing, and, if positive, sequencing. PCR and sequencing were also performed on plasma and feces samples of HAV cases.

RESULTS

In 22 out of 88 (25%) of sewage samples, HAV RNA was detected. All HAV-RNA-positive sewage samples until 8 February 2023 were subgenotype IB, matching the strain detected in all cases. Another strain of HAV (subgenotype IA) was detected in sewage from 15 February 2023 onwards, without associated cases.

CONCLUSIONS

Passive sampler-based sewage monitoring is an effective method to rapidly detect HAV shedding linked to diagnosed cases. It detects unnoticed viral infections and allows monitoring of outbreaks. This suggests that passive sampler-based monitoring is a promising tool supporting the public health response during HAV and other outbreaks.

Epidemiology of sporadic and outbreak-associated hepatitis A infections in Ontario, Canada: A descriptive summary, 2015-2022

Background

Hepatitis A is a disease of public health significance that typically causes acute, self-limiting infection. Understanding the risk factors and demographics associated with individual infections and outbreaks can guide public health communication and interventions.

Objective

To assess the number of hepatitis A cases and outbreaks in Ontario from January 1, 2015, to November 22, 2022, and to identify common risk factors associated with sporadic and outbreak-associated infections in Ontario.

Methods

Confirmed and probable hepatitis A cases reported between January 1, 2015, and November 22, 2022, were extracted from the Ontario electronic reporting system. Descriptive analyses were used to summarize and compare risk factors reported by sporadic and outbreak-associated hepatitis A cases. Annual rates of infection for individual public health units were calculated using annual population estimates for Ontario health regions.

Results

During the study period, 938 cases of hepatitis A were reported in Ontario (an average annual rate of 0.9 cases per 100,000 population), with 31.3% (n=294) of cases linked to one of 18 unique outbreaks of hepatitis A. Four of 13 local outbreaks were associated with elementary school settings. Reported risk factors differed between sporadic cases (predominantly travel-related) and cases linked to known outbreaks (anal-oral contact, illicit drug use, diapering/assisting in toileting, close contact with a case). Rates of sporadic infection differed across public health units in Ontario over the study period.

Conclusion

Public health interventions that aim to increase awareness of hepatitis A risk factors and increase vaccine uptake among those at increased risk of exposure could help to reduce the incidence of both locally acquired and travel-related sporadic infections and outbreaks.

Hepatitis A virus subtype IB outbreak among MSM in Hungary with a link to a frozen berry source

Men who have sex with men (MSM) are at high risk of acquiring hepatitis A virus (HAV) and in recent years several HAV outbreaks mostly affecting MSM have been described. These outbreaks were caused by subtype IA strains circulating in this high-risk population. After years of low incidence, an outbreak among MSM in Hungary caused a significant increase in reported HAV infections in 2022. Samples from 224 HAV IgM-positive patients diagnosed in 2022 were tested for HAV RNA and positive samples were genotyped by sequencing. In 171 patients a unique subtype IB virus was detected with 99.8-100% sequence identity in the VP1/P2A junction. It was distinct from previously published strains, but most closely related to an Egyptian isolate. Sequence analysis revealed one dominant and three minor variants based on VP1/P2A. Whole genome sequencing revealed limited variation among these variants, suggesting a recent common origin. Epidemiological data indicated that sexual transmission was driving the outbreak for most of the year, suggested by the high male to female ratio and the large number of coinfections with HIV and other sexually transmitted infections among the patients. The outbreak was also associated with a restaurant cluster, in which one of the variants was detected and frozen berries were implicated as the source of infections. The outbreak strain was also detected in other countries around Europe and remained frequently detectable in Hungary in 2023. This study provides insights into the molecular and epidemiological characteristics of the described HAV outbreak. The results show that sequencing is not only useful in connecting cases to an outbreak, but also helps to clarify the relatedness of detected variants. Prevention strategies focusing on vulnerable communities may reduce the burden of HAV infections in the future.

A Useful Method to Provide Infectious and Cultivable In Vitro Naked Viral Particles of Hepatitis A Virus

Hepatitis A virus (HAV) is an enteric virus mainly transmitted by the faecal-oral route. Belonging to the Picornaviridae family, HAV was first described as small naked particles, like all viruses of this family. However, for about a decade, it was demonstrated that HAV particles can exist surrounded by a lipid bilayer. This type of particle, called enveloped HAV (eHAV), acquires its lipid bilayer by hijacking a part of cell membranes during the virion egress in the last steps of the viral cycle. In vitro culture systems produce mainly eHAV, and so, to date, most of the studies on HAV have been carried out using this type of viral particle. In this study, a method based on lipid bilayer removal by chemical delipidation is proposed for the production of naked HAV particles. The resulting naked HAV particles conserve their infectivity and are therefore fully cultivable in vitro. By using this method, naked HAV particles can easily be produced in vitro and can be useful to perform further studies such as inactivation processes for the food industry, as HAV is a main concern for food safety.

Hepatitis A, B and C prevalence among transgender women and travestis in five Brazilian capitals between 2019-2021

OBJECTIVE

To estimate the prevalence and factors associated with hepatitis A, B, and C in transgender women and travestis's networks, in 5 regions of Brazil.

METHODS

This cross-sectional study includedtransgender women and travestis in five Brazilian capitals (Campo Grande, Manaus, Porto Alegre, Salvador, and São Paulo), between December/2019 and July/2021. All samples were subjected to detection of serological markers of hepatitis virus A (HAV), B (HBV), and C (HCV) infections through rapid tests and chemiluminescent microparticle immunoassays. Positive samples in the screening tests were submitted to detect HBV DNA and HCV-RNA by real-time PCR and genotyped by Sanger sequencing.

RESULTS

Analysis of 1,317 samples showed network prevalence rates of 69.1%, 25.1%, and 1.5% for HAV, HBV, and HCV exposure, respectively. A high susceptibility rate to HBV infection (35.7%) and low prevalence of vaccine response markers (40%) were also observed. Age greater than 26 years, self-declared black/brown skin color, having only primary education, history of incarceration, and use of a condom in the last sexual intercourse with a casual partner were associated with total anti-HAV. Exposure to HBV was associated with age greater than 26 years, self-declared black/brown, history of being a sex worker, and incarceration. Age > 37 years, history of sexual abuse, and frequent alcohol consumption were associated with hepatitis C infection.

CONCLUSION

The highest prevalence of HAV in this population was found in the North and Northeast regions, and the prevalence found was higher than that in the general population, suggesting greater vulnerability. The prevalence of HCV infection in our study was similar to that observed in the general population.

A Comparative Analysis of Drinking Water Provision and Hepatitis A Incidence in Uzbekistan in 2010-2023

Objective This study aims to analyze the relationship between access to safe drinking water and the incidence of hepatitis A in Uzbekistan from 2010 to 2023 to inform public health strategies for disease prevention. Methods We utilized hepatitis A incidence data from the Sanitary and Epidemiological Well-Being and Public Health Authority and drinking water provision data from the Government Statistics Agency of Uzbekistan. A linear regression analysis was performed using R 4.3.2 to investigate the correlation between these variables. The study examined hepatitis A cases per 100,000 population and the percentage of households with access to safe drinking water. Results Hepatitis A incidence fluctuated significantly over the study period, with a notable spike to 162 cases per 100,000 population in 2023, despite relatively stable access to safe drinking water (ranging from 67.4% to 77% of households). The analysis revealed a complex relationship between water access and hepatitis A incidence. The linear regression coefficient was 3.89 (adjusted R-squared: 0.3021, P-value: 0.02), indicating that each growing percent of water supply is raising the incidence of hepatitis 3.89 cases of hepatitis infection. Conclusion The reverse effect of water supply percentage and the incidence of hepatitis A incidence in Uzbekistan suggests that other factors play significant roles in disease transmission. These may include sanitation practices, hygiene behaviors, and vaccination coverage. The findings emphasize the need for a multifaceted approach to hepatitis A prevention, incorporating improved water infrastructure, enhanced sanitation, public education, and comprehensive vaccination programs. Further research is needed to identify specific determinants of hepatitis A transmission in Uzbekistan to guide targeted interventions and public health policies.

Wastewater surveillance for viral pathogens: A tool for public health

A focus on water quality has intensified globally, considering its critical role in sustaining life and ecosystems. Wastewater, reflecting societal development, profoundly impacts public health. Wastewater-based epidemiology (WBE) has emerged as a surveillance tool for detecting outbreaks early, monitoring infectious disease trends, and providing real-time insights, particularly in vulnerable communities. WBE aids in tracking pathogens, including viruses, in sewage, offering a comprehensive understanding of community health and lifestyle habits. With the rise in global COVID-19 cases, WBE has gained prominence, aiding in monitoring SARS-CoV-2 levels worldwide. Despite advancements in water treatment, poorly treated wastewater discharge remains a threat, amplifying the spread of water-, sanitation-, and hygiene (WaSH)-related diseases. WBE, serving as complementary surveillance, is pivotal for monitoring community-level viral infections. However, there is untapped potential for WBE to expand its role in public health surveillance. This review emphasizes the importance of WBE in understanding the link between viral surveillance in wastewater and public health, highlighting the need for its further integration into public health management.

Prevalence of hepatitis A virus among migrant workers in Qatar: A national study

BACKGROUND

Hepatitis A virus (HAV) is the predominant cause of acute viral hepatitis worldwide; however, data on HAV antibody prevalence (seroprevalence) among migrant populations are limited. This study aimed to investigate HAV seroprevalence among Qatar's migrant craft and manual workers (CMWs), constituting approximately 60% of the country's population.

METHODS

HAV antibody testing was conducted on stored serum specimens obtained from CMWs during a nationwide severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) population-based cross-sectional survey between July 26 and September 9, 2020. Associations with HAV infection were investigated through regression analyses.

RESULTS

Of the 2,607 specimens with HAV antibody test results, 2,393 were positive, and 214 were negative. The estimated HAV seroprevalence among CMWs was 92.0% (95% CI: 90.9-93.1%). HAV seroprevalence was generally high but exhibited some variation, ranging from 70.9% (95% CI: 62.4-78.2%) among Sri Lankans to 99.8% (95% CI: 98.2-99.9%) among Pakistanis. The multivariable regression analysis identified age, nationality, and educational attainment as statistically significant factors associated with HAV infection. Relative to CMWs aged ≤29 years, the adjusted relative risk (ARR) was 1.06 (95% CI: 1.03-1.10) in CMWs aged 30-39 years and reached 1.15 (95% CI: 1.10-1.19) in those aged ≥50 years. In comparison to Indians, the ARR was lower among Sri Lankans, assessed at 0.81 (95% CI: 0.72-0.91), but higher among Nepalese at 1.07 (95% CI: 1.04-1.11), Bangladeshis at 1.10 (95% CI: 1.07-1.13), Pakistanis at 1.12 (95% CI: 1.09-1.15), and Egyptians at 1.15 (95% CI: 1.08-1.23). No evidence for differences was found by geographic location or occupation.

CONCLUSIONS

HAV seroprevalence among Qatar's CMW population is very high, with over nine out of every ten individuals having been exposed to this infection, likely during childhood.

Hepatitis A in Latin America: The current scenario

This review aims to gather and disseminate updated information regarding hepatitis A virus (HAV) in Latin America (LA) in the last 11 years, including seroprevalence, post-vaccination studies, virus detection in aqueous matrices and food samples, and outbreak reports. Only 24 seroprevalence studies were published between 2012 and 2023 with 55%-100% reported prevalences of anti-HAV IgG. Among the 25 LA countries, only eight of them have introduced HAV vaccines into their immunisation programs. Outbreaks of hepatitis A occurred between 2017-2019, mainly affecting men who have sex with men in Argentina, Brazil and Chile, probably as a consequence of the abrupt decline of young adults' immunity. This could be due to that young adult have never been infected in childhood (due to socio-health improvements) and are above the cut-off ages to be included when the vaccination programs were introduced. Although scarce, studies focused on environmental and food HAV surveillance have shown viral presence in these samples. Surface waters presented HAV detections between 1.2% and 86.7%, and untreated wastewaters between 2.8% and 70.9%. Genotypes found in all cases were IA and IC. The only wastewater-based epidemiology study showed to be a useful tool as a complement of traditional epidemiological surveillance. Only four LA countries have looked for HAV in food samples, with genome detection rates between 9% and 33%. Latin American HAV circulation scenario is changing. In countries where socioeconomic and sanitary conditions have not improved, the virus persists with high endemicity and the access to the vaccine should be re-evaluated by local governments. In countries where access to clean water, better sanitary conditions and HAV immunisation programs have been implemented, the number of cases among young adults seems to be increasing, alerting health authorities.

Modeling hepatitis A epidemiological profiles and estimating the pediatric vaccination threshold in the Russian Federation

Background

To combat the hesitancy towards implementing a hepatitis A universal mass vaccination (UMV) strategy and to provide healthcare authorities with a comprehensive analysis of the potential outcomes and benefits of the implementation of such a vaccination program, we projected HAV seroprevalence and incidence rates in the total population of the Russian Federation and estimated the pediatric vaccination threshold required to achieve an incidence level of less than 1 case per 100,000 using a new mathematical model.

Methods

A dynamic age-structured SEIRV (susceptible-exposed-infectious-recovered-vaccinated) compartmental model was developed and calibrated using demographic, seroprevalence, vaccination, and epidemiological data from different regions of the Russian Federation. This model was used to project various epidemiological measures.

Results

The projected national average age at the midpoint of population immunity increases from 40 years old in 2020 to 50 years old in 2036 and is shifted even further to the age of 70 years in some regions of the country. An increase of varying magnitude in the incidence of symptomatic HAV infections is predicted for all study regions and for the Russian Federation as a whole between 2028 and 2032, if the HAV vaccination coverage level remains at the level of 2022. The national average vaccination coverage level required to achieve a symptomatic HAV incidence rate below 1 case per 100,000 by 2032 was calculated to be 69.8% if children aged 1-6 years are vaccinated following the implementation of a UMV program or 34.8% if immunization is expanded to children aged 1-17 years.

Conclusion

The developed model provides insights into a further decline of herd immunity to HAV against the background of ongoing viral transmission. The current favorable situation regarding hepatitis A morbidity is projected to be replaced by an increase in incidence rates if vaccination coverage remains at the current levels. The obtained results support the introduction of a hepatitis A UMV strategy in the Russian Federation.

Identification and Genomic Characterization of Two Novel Hepatoviruses in Shrews from Yunnan Province, China

Hepatitis A virus (HAV), a member of the genus Hepatovirus (Picornaviridae HepV), remains a significant viral pathogen, frequently causing enterically transmitted hepatitis worldwide. In this study, we conducted an epidemiological survey of HepVs carried by small terrestrial mammals in the wild in Yunnan Province, China. Utilizing HepV-specific broad-spectrum RT-PCR, next-generation sequencing (NGS), and QNome nanopore sequencing (QNS) techniques, we identified and characterized two novel HepVs provisionally named EpMa-HAV and EpLe-HAV, discovered in the long-tailed mountain shrew (Episoriculus macrurus) and long-tailed brown-toothed shrew (Episoriculus leucops), respectively. Our sequence and phylogenetic analyses of EpMa-HAV and EpLe-HAV indicated that they belong to the species Hepatovirus I (HepV-I) clade II, also known as the Chinese shrew HepV clade. Notably, the codon usage bias pattern of novel shrew HepVs is consistent with that of previously identified Chinese shrew HepV. Furthermore, our structural analysis demonstrated that shrew HepVs differ from other mammalian HepVs in RNA secondary structure and exhibit variances in key protein sites. Overall, the discovery of two novel HepVs in shrews expands the host range of HepV and underscores the existence of genetically diverse animal homologs of human HAV within the genus HepV.

Healthcare and Epidemiological Surveillance Costs of Hepatitis A Outbreaks in Spain in Regions with and without Universal Hepatitis A Vaccination of Children during 2010-2018

The aim of this study was to evaluate and compare hepatitis A outbreak-associated healthcare and epidemiological surveillance costs in Spain in two types of autonomous regions during 2010-2018: (1) regions with a prevention strategy based on universal hepatitis A vaccination of children and vaccination of high-risk population groups (Catalonia) and (2) regions with a prevention strategy based on vaccinating high-risk population groups (Castile and Leon, Murcia, Navarra, Community of Madrid, Community of Valencia). Healthcare costs were determined based on the resources used to treat hepatitis A outbreak-associated cases and hospitalizations. Epidemiological surveillance costs were calculated from the resources used during surveillance activities. The ratios for total, healthcare and epidemiological surveillance costs (regions without universal hepatitis A vaccination of children vs. Catalonia) were used to compare the two hepatitis A prevention strategies. From 2010 to 2018, the total, healthcare and epidemiological surveillance costs per million population were 1.75 times (EUR 101,671 vs. EUR 58,032), 1.96 times (EUR 75,500 vs. EUR 38,516) and 1.34 times greater (EUR 26,171 vs. EUR 19,515) in regions without universal hepatitis A vaccination of children than in Catalonia, respectively. The ratios tended to increase over time during 2010-2018. In 2015-2018, total, healthcare and epidemiological surveillance costs per million population were 2.68 times (EUR 69,993 vs. EUR 26,158), 2.86 times (EUR 53,807 vs. EUR 18,825) and 2.21 times greater (EUR 16,186 vs. EUR 7333) in regions without universal hepatitis A vaccination of children than in Catalonia, respectively. These findings suggest that universal hepatitis A vaccination of children could reduce hepatitis A outbreak-associated costs.

Global burden and trends of acute viral hepatitis among children and adolescents from 1990 to 2019: a systematic analysis of the Global Burden of Disease Study 2019

BACKGROUND

Children and adolescents are at high risk for acute viral hepatitis (AVH), but epidemiological research focusing on them has been overshadowed by adult chronic B and C. We provide global, regional, and national estimates of the AVH burden and their trends on people under 20 years from 1990 to 2019.

METHODS

AVH data from Global Burden of Disease Study (GBD) 2019 was used. Incidence and disability-adjusted life years (DALYs) were calculated, analyzing trends with estimated annual percentage change (EAPC) and Joinpoint regression.

RESULTS

In 2019, 156.39 (95% uncertainty interval 145.20-167.16) million new cases of AVH were reported among children and adolescents globally, resulting in 1.98 (1.50-2.55) million DALYs. Incidence rates for young children (< 5 years), older children (5-9 years), and adolescents (10-19 years) were 12,799 (11,068-14,513), 5,108 (4829-5411), and 3020 (2724-3339) per 100,000 population, respectively. The global AVH incidence displayed a linear decline with an EAPC of - 0.66 (- 0.68 to - 0.65). High-incidence regions included sub-Saharan Africa, Oceania, South Asia, and Central Asia, with India, Pakistan, and Nigeria facing the greatest burden. Leading causes were hepatitis A, followed by hepatitis E, B, and C. All hepatitis types showed declining trends, especially hepatitis B. Furthermore, we confirmed the association between the AVH incidence and the socioeconomics, vaccine, and advanced liver diseases.

CONCLUSION

Effective vaccines and treatments for hepatitis B and C offer eradication opportunities. Broadening diagnostic and therapeutic coverage is vital to address disparities in service provision for children and adolescents.

The intersection of virus infection and liver disease: A comprehensive review of pathogenesis, diagnosis, and treatment

Liver disease represents a significant global burden, placing individuals at a heightened risk of developing cirrhosis and liver cancer. Viral infections act as a primary cause of liver diseases on a worldwide scale. Infections involving hepatitis viruses, notably hepatitis B, C, and E viruses, stand out as the most prevalent contributors to acute and chronic intrahepatic adverse outcome, although the hepatitis C virus (HCV) can be effectively cured with antiviral drugs, but no preventative vaccination developed. Hepatitis B virus (HBV) and HCV can lead to both acute and chronic liver diseases, including liver cirrhosis and hepatocellular carcinoma (HCC), which are principal causes of worldwide morbidity and mortality. Other viruses, such as Epstein-Barr virus (EBV) and cytomegalovirus (CMV), are capable of causing liver damage. Therefore, it is essential to recognize that virus infections and liver diseases are intricate and interconnected processes. A profound understanding of the underlying relationship between virus infections and liver diseases proves pivotal in the effective prevention, diagnosis, and treatment of these conditions. In this review, we delve into the mechanisms by which virus infections induce liver diseases, as well as explore the pathogenesis, diagnosis, and treatment of liver diseases. This article is categorized under: Infectious Diseases > Biomedical Engineering.

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.

Trends of Hepatitis A Virus Infection in Poland: Assessing the Potential Impact of the COVID-19 Pandemic and War in Ukraine

Hepatitis A virus (HAV) is the most common cause of acute viral hepatitis, which is preventable by vaccination. This study analyzed trends of HAV infections in Poland according to socio-demographic features in the years 2009-2022 and assessed the potential impact of the COVID-19 pandemic (2020-2023) and the migration of war refugees from Ukraine (since February 2022). In 2009-2022, 7115 new cases of HAV infection were diagnosed in Poland, especially among men (66.4%) and in urban areas (77.4%). Infections among men were most common at the age of 25-34 (median rate 0.43 per 105) and in women aged 15-24 (median rate 0.39 per 105). Analysis of the 14-year frequency of HAV infections exhibited three trends, regardless of gender, age, and residence. The infections revealed a downward trend in 2009-2014, increased significantly in 2014-2018, and decreased again after 2018. A particularly rapid increase in HAV infections occurred between March 2017 and February 2018 (median rate 0.79 per 105). The high level of new infections persisted until the beginning of the COVID-19 pandemic, at which point it dropped significantly but did not reach the level recorded before March 2017. During the Omicron SARS-CoV-2 dominance period, the median rate of HAV infections was 0.053 per 105, with a four-fold increase being observed from February 2022 (when the migration of war refugees from Ukraine began) to August 2022. The presented results can serve as a reference point for further observations in Central Europe. The HAV epidemiological situation is unlikely to escalate in Poland but requires further monitoring.

Heat stability of foodborne viruses - Findings, methodological challenges and current developments

Heat treatment of food represents an important measure to prevent pathogen transmission. Thus far, evaluation of heat treatment processes is mainly based on data from bacteria. However, foodborne viruses have gained increasing attention during the last decades. Here, the published literature on heat stability and inactivation of human norovirus (NoV), hepatitis A virus (HAV) and hepatitis E virus (HEV) was reviewed. Data for surrogate viruses were not included. As stability assessment for foodborne viruses is often hampered by missing infectivity assays, an overview of applied methods is also presented. For NoV, molecular capsid integrity assays were mainly applied, but data from initial studies utilizing novel intestinal enteroid or zebrafish larvae assays are available now. However, these methods are still limited in applicability and sensitivity. For HAV, sufficient cell culture-based inactivation data are available, but almost exclusively for one single strain, thus limiting interpretation of the data for the wide range of field strains. For HEV, data are now available from studies using pig inoculation or cell culture. The results of the reviewed studies generally indicate that NoV, HAV and HEV possess a high heat stability. Heating at 70-72 °C for 2 min significantly reduces infectious titers, but often does not result in a >4 log10 decrease. However, heat stability greatly varied dependent on virus strain, matrix and heating regime. In addition, the applied method largely influenced the result, e.g. capsid integrity assays tend to result in higher measured stabilities than cell culture approaches. It can be concluded that the investigated foodborne viruses show a high heat stability, but can be inactivated by application of appropriate heating protocols. For HAV, suggestions for safe time/temperature combinations for specific foods can be derived from the published studies, with the limitation that they are mostly based on one strain only. Although significant improvement of infectivity assays for NoV and HEV have been made during the last years, further method development regarding sensitivity, robustness and broader applicability is important to generate more reliable heat inactivation data for these foodborne viruses in future.

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.

Recent advances in hepatitis A virus research and clinical practice guidelines for hepatitis A virus infection in Japan

In 2018, there was a hepatitis A outbreak in Japan, and hepatitis A virus (HAV) infection is considered a sexually transmitted disease. In general, patients with hepatitis A should be given attention, and this disease should be prevented more than ever. The Japan Agency for Medical Research and Development (AMED) Hepatitis A and E viruses (HAV and HEV) Study Group has worked on the project to create "Recent Advances in Hepatitis A Virus (HAV) Research and Clinical Practice Guidelines for HAV Infection in Japan". The group consists of expert hepatologists and virologists who gathered at virtual meeting on August 5, 2023. Data about the pathogenesis, infection routes, diagnosis, complications, several factors for the severities, vaccination, and current and future treatments for hepatitis A were discussed and debated for a draft version. The participants assessed the quality of cited studies. The finalized recommendations are presented in this review. The recent advances in HAV research and clinical practice for HAV infection in Japan, have been reviewed by the AMED HAV and HEV Study Group.

Alzheimer's disease as a viral disease: Revisiting the infectious hypothesis

Alzheimer's disease (AD) represents the most frequent type of dementia in elderly people. Two major forms of the disease exist: sporadic - the causes of which have not yet been fully understood - and familial - inherited within families from generation to generation, with a clear autosomal dominant transmission of mutations in Presenilin 1 (PSEN1), 2 (PSEN2) or Amyloid Precursors Protein (APP) genes. The main hallmark of AD consists of extracellular deposits of amyloid-beta (Aβ) peptide and intracellular deposits of the hyperphosphorylated form of the tau protein. An ever-growing body of research supports the viral infectious hypothesis of sporadic forms of AD. In particular, it has been shown that several herpes viruses (i.e., HHV-1, HHV-2, HHV-3 or varicella zoster virus, HHV-4 or Epstein Barr virus, HHV-5 or cytomegalovirus, HHV-6A and B, HHV-7), flaviviruses (i.e., Zika virus, Dengue fever virus, Japanese encephalitis virus) as well as Human Immunodeficiency Virus (HIV), hepatitis viruses (HAV, HBV, HCV, HDV, HEV), SARS-CoV2, Ljungan virus (LV), Influenza A virus and Borna disease virus, could increase the risk of AD. Here, we summarized and discussed these results. Based on these findings, significant issues for future studies are also put forward.

Knowledge, Attitudes, and Practices of European Healthcare Professionals towards Hepatitis A and Hepatitis B Vaccination in at-Risk Adults

Despite the occurrence of several hepatitis A (hepA) and hepatitis B (hepB) outbreaks in Europe in the last few decades, not all European countries have implemented hepA and hepB vaccinations in their national immunization programs, especially for adults at risk for hepA and/or hepB infection, such as men who have sex with men or patients with chronic liver disease. Currently, little is known on the attitudes of European healthcare professionals (HCPs) towards hepA and hepB vaccinations for at-risk adults. We conducted an online survey among HCPs in Germany, Spain, and the United Kingdom to assess their awareness of and adherence to their national hepA and hepB vaccination guidelines for at-risk adults. Among the 698 HCPs who took the survey, most (91.1%) were familiar with their national vaccination recommendations and always followed them or followed them most of the time when advising or prescribing hepA or hepB vaccines. Major and moderate barriers for recommending or administering such vaccines were the non-disclosure of risk factors by the patient (53.0-57.6%) and the patient's lack of motivation or knowledge about the risk of the disease (50.3-52.9%). These results may help inform strategies to improve and accelerate hepA and hepB vaccination in European at-risk adults.

Seroprevalence of hepatitis A virus antibodies among children and adolescents living in Northern Thailand: an implication for hepatitis A immunization

This cross-sectional study aimed to assess seroprevalence of hepatitis A virus (HAV) antibodies and identify factors associated with HAV seropositivity among children and adolescents aged 1-18 years who resided in Chiang Mai, Thailand. Sociodemographic characteristics, sanitation/hygiene, and history of HAV vaccination were collected. Anti-HAV IgG antibody was determined, and a level ≥ 1.0 S/CO defined HAV seropositivity. We enrolled 300 participants; median age 8.7 years, 54% male, and 13% overweight (BMI z-score: + 1 to + 2 standard deviation [SD]). Sixty-five participants (22%) were vaccinated against HAV. Overall, 84/300 participants (28%) demonstrated HAV seropositivity, of whom 55/65 (85%) and 29/235 (12%) were among vaccinated and unvaccinated participants (P < 0.001), respectively. Previous HAV vaccination (adjusted odds ratio [aOR] 47.2; 95% CI 20.0-111.8) and overweight (aOR 4.4; 95% CI 1.7-11.3, compared with normal weight [BMI z-score: - 2 to + 1 SD]) were significantly associated with seropositivity of HAV. In the stratified analyses, crowded bedroom (aOR 3.2; 95% CI 1.3-7.8, per one person increase) and overweight (aOR 5.0; 95% CI 1.8-13.7) were factors associated with HAV seropositivity among vaccinated and unvaccinated participants, respectively. Seroprevalence of HAV antibodies in healthy Thai children and adolescents was relatively low. Recommendation of HAV vaccination for these populations, particularly those with high-risk conditions, should be considered.

Hepatitis A virus infection

Hepatitis A is a vaccine-preventable infection caused by the hepatitis A virus (HAV). Over 150 million new infections of hepatitis A occur annually. HAV causes an acute inflammatory reaction in the liver that usually resolves spontaneously without chronic sequelae. However, up to 20% of patients experience a prolonged or relapsed course and <1% experience acute liver failure. Host factors, such as immunological status, age, pregnancy and underlying hepatic diseases, can affect the severity of disease. Anti-HAV IgG antibodies produced in response to HAV infection persist for life and protect against re-infection; vaccine-induced antibodies against hepatitis A confer long-term protection. The WHO recommends vaccination for individuals at higher risk of infection and/or severe disease in countries with very low and low hepatitis A virus endemicity, and universal childhood vaccination in intermediate endemicity countries. To date, >25 countries worldwide have implemented such programmes, resulting in a reduction in the incidence of HAV infection. Improving hygiene and sanitation, rapid identification of outbreaks and fast and accurate intervention in outbreak control are essential to reducing HAV transmission.

Impact of frequency and duration of freeze-dried inactivated tissue culture hepatitis A vaccine (Aimmugen®) vaccination on antibody titers; a japanese cross-sectional study

BACKGROUND

The effect of the timing of additional doses and the long-term persistence of lyophilized inactivated tissue culture hepatitis A (HA) vaccine (Aimmugen®) on antibodies is unknown.

METHODS

A single-center, cross-sectional, observational study was conducted in collaboration with the Japan Air Self-Defense Force, whose personnel were immunized with Aimmugen® when deployed to endemic areas. Patients who consented to this study after a medical examination with blood sampling between June 2022 and February 2023 were included; HA-IgG level in the residual serum was measured using the chemiluminescent immunoassay method. The exact vaccination history was investigated based on immunization records maintained by the Ministry of Defense, and a questionnaire was used to collect confounding factors.

RESULTS

Of the 181 participants observed, 49 were in the unvaccinated group, and 132 were in the vaccinated group. Out of the vaccinated group, 6.8 % received either one or two doses, 40.9 % received three doses, and 52.3 % received more than four doses. IgG antibody titers (S/CO value) in each group (0, 1 or 2, 3, and over 4) increased in a frequency-dependent manner, with those vaccinated over four times showing significantly higher IgG antibody titers than all other groups (0.19 ± 0.10 vs 3.66 ± 3.00 vs 7.63 ± 3.57 vs 10.57 ± 1.86, respectively). When the number of months elapsed from the last vaccination to the date of blood collection in each group was plotted against IgG antibody titer, the slope of the regression line flattened out from a decreasing trend in the order 1 or 2, 3, over 4.

CONCLUSIONS

Three doses of Aimmugen® are efficacious, but four or more doses induce more robust and sustained antibody production. Additionally, four or more doses may be effective when there is a need to ensure long-term immunity or risk of prolonged exposure.

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.

Sex differences in hepatitis A incidence rates-a multi-year pooled-analysis based on national data from nine high-income countries

BACKGROUND

Possible sex differences in hepatitis A virus (HAV) incidence rates in different age groups are not well documented. We aimed to obtain stable pooled estimates of such differences based on data from a number of high-income countries.

METHODS

We obtained data on incident cases of HAV by sex and age group over a period of 6-25 years from nine countries: Australia, Canada, Czech Republic, Finland, Germany, Israel, Netherland, New Zealand and Spain. Male to female incidence rate ratios (IRR) were computed for each year, by country and age group. For each age group, we used meta-analytic methods to combine the IRRs. Meta-regression was conducted to estimate the effects of age, country, and time period on the IRR.

RESULTS

A male excess in incidence rates was consistently observed in all age groups, although in the youngest and oldest age groups, where the numbers tended to be lower, the lower bounds of the 95% confidence intervals for the IRRs were less than one. In the age groups <1, 1-4, 5-9, 10-14, 15-44, 45-64 and 65+, the pooled IRRs (with 95% CI) over countries and time periods were 1.18 (0.94,1.48), 1.22 (1.16,1.29), 1.07 (1.03,1.11), 1.09 (1.04,1.14), 1.46 (1.30,1.64), 1.32 (1.15,1.51) and 1.10 (0.99,1.23) respectively.

CONCLUSIONS

The excess HAV incidence rates in young males, pooled over a number of countries, suggest that the sex differences are likely to be due at least in part to physiological and biological differences and not just behavioral factors. At older ages, differential exposure plays an important role. These findings, seen in the context of the excess incidence rates in young males for many other infectious diseases, can provide further keys to the mechanisms of the infection.

Comparative Analysis on Clinical Characteristics Among Patients with Acute Hepatitis A Virus (HAV) and Patients with Acute Hepatitis E Virus (HEV): A Single-Center Retrospective Study from Bulgaria

Introduction

The acute viral hepatitis was one of the most common conditions in daily clinical practice varying in different parts of the world. The aim of the present study was to perform a comparative analysis on clinical characteristics among patients with acute hepatitis A virus (HAV) infection and patients with acute hepatitis E virus (HEV) infection admitted to the Military Medical Academy (MMA), Sofia, Bulgaria.

Methods

A retrospective study was performed at MMA, between 1 January 2016 and 31 December 2021. The etiological diagnosis was confirmed by enzyme-linked immunosorbent assay (ELISA) HAV/HEV IgM serology assays.

Results

The current survey included 231 patients with mean age 45.11 ± 16.08 years (95% confidence interval: 43.04-47.19). According to the case definition, inclusion and exclusion criteria, persons were divided into two groups: patients with acute HAV infection (68.4%; 158/231) and patients with acute HEV infection (31.6%; 73/231). Males with HEV had 3.091 times the odds of comorbidity "hypertension" than males with HAV (p = 0.032). There were almost equal odds of increased ALT (odds ratio = 0.999; p = 0.003) in men with HEV and men with HAV. Females with HEV had 5.161 times the odds of comorbidity "hypertension" compared with females with HAV (p = 0.049). We found almost equal odds for elevated ALT in women with HEV and women with HAV (OR = 0.999; p = 0.025). In the non-elderly group (<60-year-old), HEV individuals had 4.544 and 10.560 times the odds of comorbidities "hypertension" and "cardiovascular diseases" compared with HAV patients (p < 0.05). We found almost equal odds for elevated ALT in HEV patients and HAV participants (OR = 0.998; p = 0.002).

Conclusion

The results from the current study may support the physicians daily care for patients with acute HAV and acute HEV.

Potential of CRISPR/Cas system as emerging tools in the detection of viral hepatitis infection

Viral hepatitis, the most common cause of inflammatory liver disease, affects hundreds of millions of people worldwide. It is most commonly associated with one of the five nominal hepatitis viruses (hepatitis A-E viruses). HBV and HCV can cause acute infections and lifelong, persistent chronic infections, while HAV and HEV cause self-limiting acute infections. HAV and HEV are predominantly transmitted through the fecal-oral route, while diseases transmitted by the other forms are blood-borne diseases. Despite the success in the treatment of viral hepatitis and the development of HAV and HBV vaccines, there is still no accurate diagnosis at the genetic level for these diseases. Timely diagnosis of viral hepatitis is a prerequisite for efficient therapeutic intervention. Due to the specificity and sensitivity of clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated sequences (Cas) technology, it has the potential to meet critical needs in the field of diagnosis of viral diseases and can be used in versatile point-of-care (POC) diagnostic applications to detect viruses with both DNA and RNA genomes. In this review, we discuss recent advances in CRISPR-Cas diagnostics tools and assess their potential and prospects in rapid and effective strategies for the diagnosis and control of viral hepatitis infection.

Prolonged Cholestasis Following Acute Hepatitis A Infection: Case Report and a Review of Literature

Prolonged cholestasis is a rare complication of hepatitis A infection, characterized by a protracted, indolent course with persistent symptoms of pruritus and malabsorption lasting for several months. A 14-year-old girl, previously treated for acute hepatitis A, presented with yellowing of the eyes. An evaluation of her liver function revealed conjugated hyperbilirubinemia, and a liver biopsy confirmed hepatitis with cholestasis. Fortunately, she responded well to conservative treatment and recovered successfully.

From Mystery to Clarity: Uncovering the Possible Cause of Hepatitis Outbreak in Children

Hepatitis A is a viral infection that can cause liver inflammation and damage. Hepatitis A outbreaks in children are of particular concern due to the potential long-term health effects they can have. In recent years, several outbreaks of hepatitis A have been reported worldwide, affecting mainly children and young adults. Since 2016, hepatitis A outbreaks have been reported in 37 states of the United States alone, involving approximately 44,650 cases, 27,250 hospitalizations, and 415 deaths as of September 23, 2022. The epidemiology of hepatitis A outbreaks in children is complex and multifactorial, with various risk factors such as poor sanitation and hygiene practices, crowded living conditions, low socioeconomic status, lack of vaccination, and travel to endemic areas. Investigations of outbreaks involve identifying suspected cases, laboratory testing, contact tracing, and investigation of possible sources of infection. Contaminated food and water, poor sanitation and hygiene procedures, intimate contact with infected people, and environmental variables are all potential causes of outbreaks in children. Preventive measures include vaccination, improving sanitation and hygiene practices, food safety and inspection, and health education and community outreach programs. Understanding the epidemiology of hepatitis A outbreaks in children and the risk factors associated with infection is essential for developing effective preventive strategies and reducing the global burden of this disease.

Treatment Options for Hepatitis A and E: A Non-Systematic Review

Hepatitis A and hepatitis E are relatively common causes of liver disease. Both viruses are mainly transmitted through the faecal-oral route and, consequently, most outbreaks occur in countries with poor sanitation. An important role of the immune response as the driver of liver injury is also shared by the two pathogens. For both the hepatitis A (HAV) and hepatitis E (HEV) viruses, the clinical manifestations of infection mainly consist of an acute disease with mild liver injury, which results in clinical and laboratory alterations that are self-limiting in most cases. However, severe acute disease or chronic, long-lasting manifestations may occur in vulnerable patients, such as pregnant women, immunocompromised individuals or those with pre-existing liver disease. Specifically, HAV infection rarely results in fulminant hepatitis, prolonged cholestasis, relapsing hepatitis and possibly autoimmune hepatitis triggered by the viral infection. Less common manifestations of HEV include extrahepatic disease, acute liver failure and chronic HEV infection with persistent viraemia. In this paper, we conduct a non-systematic review of the available literature to provide a comprehensive understanding of the state of the art. Treatment mainly consists of supportive measures, while the available evidence for aetiological treatment and additional agents in severe disease is limited in quantity and quality. However, several therapeutic approaches have been attempted: for HAV infection, corticosteroid therapy has shown outcome improvement, and molecules, such as AZD 1480, zinc chloride and heme oxygenase-1, have demonstrated a reduction in viral replication in vitro. As for HEV infection, therapeutic options mainly rely on the use of ribavirin, and some studies utilising pegylated interferon-alpha have shown conflicting results. While a vaccine for HAV is already available and has led to a significant reduction in the prevalence of the disease, several vaccines for HEV are currently being developed, with some already available in China, showing promising results.

HAV-induced acalculous cholecystitis: A case report and literature review

Hepatitis A virus (HAV) has some life-threatening extrahepatic complications, such as acute acalculous cholecystitis (AAC). We present HAV-induced AAC in a young female, based on clinical, laboratory, and imaging findings, and conduct a literature review. The patient became irritable, which progressed to lethargy, as well as a significant decline in liver function, indicating acute liver failure (ALF). She was immediately managed in the intensive care unit with close airway and hemodynamic monitoring after being diagnosed with ALF (ICU). The patient's condition was improving, despite only close monitoring and supportive treatment with ursodeoxycholic acid (UDCA) and N-acetyl cysteine (NAC).

Global burden of Liver Disease: 2023 Update

Liver disease accounts for 2 million deaths and is responsible for 4% of all deaths (1 out of every 25 deaths worldwide); approximately 2/3 of all liver related deaths occur in men. Deaths are largely attributable to complications of cirrhosis and hepatocellular carcinoma, with acute hepatitis accounting for a smaller proportion of deaths. The most common causes of cirrhosis worldwide are related to viral hepatitis, alcohol, and nonalcoholic fatty liver disease (NAFLD). Hepatotropic viruses are the etiological factor in most cases of acute hepatitis, but drug-induced liver injury increasingly accounts for a significant proportion of cases. This iteration of the global burden of liver disease is an update of the 2019 version and focuses mainly on areas where significant new information is available like alcohol-associated liver disease, NAFLD, viral hepatitis, and HCC. We also devote a separate section to the burden of liver disease in Africa, an area of the world typically neglected in such documents.

Hepatitis A virus (HAV) RNA detection in Polish blood donors and likely transmissions through blood components during the 2017-2019 epidemic

BACKGROUND

In Poland, hepatitis A virus (HAV) RNA screening was performed in plasma for fractionation usually immediately before shipment.

OBJECTIVE

Our goal was to study epidemiology, rate of transfusion transmitted HAV during epidemic (2017-2019), and viral characteristics of infected plasma donors.

STUDY DESIGN AND METHODS

HAV RNA was tested in 1,866,590 donations from 1,210,423 donors using RT-PCR in mini pools of 96 (MP96) or TMA in MP16. Virological characteristics included RNA level (RL), antibody testing, and sequencing.

RESULTS

Twenty-one HAV infections were identified (1.13/100,000 donations; 95% confidence interval [95% CI]: 0.74-1.72) and (1.73/100,000 donors; 95% CI: 1.35-2.65). The Blood Transfusion Centers were also informed about three donors, who were hospitalized for hepatitis A soon after their blood donation. In addition, we identified a donor, who had reactive result for HAV after receiving HAV vaccination. He tested positive twice 10 days after receiving the first and the second dose. The highest RL was 16 million IU/ml, mean 1,706,905 IU/ml, and median 220 IU/ml. The longest detectable RL lasted for 113 days. HAV-infected donors were seronegative (36%) or IgM positive (64%). We followed up on 12 HAV contaminated blood components issued for transfusion. In two out of seven identified patients viral transmission was confirmed (28.6%).

CONCLUSION

Based on our results, we propose a 6 month deferral after HAV infection and 14 days post HAV vaccination. The infectivity rate was below 30%. The HAV RNA testing could be considered as an additional safeguard against HAV transmission at the time of increased incidence of HAV infections in the general population.

Dual Infection of Hepatitis A Virus and Hepatitis E Virus- What Is Known?

Viral hepatitis is an infection of human hepatocytes resulting in liver damage. Dual infection of two hepatotropic viruses affects disease outcomes. The hepatitis A virus (HAV) and hepatitis E virus (HEV) are two enterically transmitted viruses; they are single-stranded RNA viruses and have common modes of transmission. They are transmitted mainly by the fecal-oral route and ingestion of contaminated food, though the HAV has no animal reservoirs. The HAV and HEV cause acute self-limiting disease; however, the HEV, but not HAV, can progress to chronic and extrahepatic infections. The HAV/HEV dual infection was reported among acute hepatitis patients present in developing countries. The impact of the HAV/HEV on the prognosis for acute hepatitis is not completely understood. Studies showed that the HAV/HEV dual infection increased abnormalities in the liver leading to fulminant hepatic failure (FHF) with a higher mortality rate compared to infection with a single virus. On the other hand, other reports showed that the clinical symptoms of the HAV/HEV dual infection were comparable to symptoms associated with the HAV or HEV monoinfection. This review highlights the modes of transmission, the prevalence of the HAV/HEV dual infection in various countries and among several study subjects, the possible outcomes of this dual infection, potential model systems for studying this dual infection, and methods of prevention of this dual infection and its associated complications.

Hepatitis A: Viral Structure, Classification, Life Cycle, Clinical Symptoms, Diagnosis Error, and Vaccination

Hepatitis A virus (HAV) is one of the well-known viruses that cause hepatitis all around the globe. Although this illness has decreased in developed countries due to extensive immunization, numerous developing and under-developed countries are struggling with this virus. HAV infection can be spread by oral-fecal contact, and there are frequent epidemics through nutrition. Improvements in socioeconomic and sanitary circumstances have caused a shift in the disease's prevalence worldwide. Younger children are usually asymptomatic, but as they become older, the infection symptoms begin to appear. Symptoms range from slight inflammation and jaundice to acute liver failure in older individuals. While an acute infection may be self-limiting, unrecognized persistent infections, and the misapplication of therapeutic methods based on clinical guidelines are linked to a higher incidence of cirrhosis, hepatocellular carcinoma, and mortality. Fortunately, most patients recover within two months of infection, though 10-15% of patients will relapse within the first six months. A virus seldom leads to persistent infection or liver damage. The mainstay of therapy is based on supportive care. All children from 12-23 months, as well as some susceptible populations, should receive routine vaccinations, according to the Centers for Disease Control and Prevention and the American Academy of Pediatrics. Laboratory diagnosis of HAV is based on antigen detection, checking liver enzyme levels, and antibody screening. Furthermore, polymerase chain reaction (PCR) technology has identified HAV in suspected nutrition sources; therefore, this technique is used for preventative measures and food-related laws.

HEPATITIS A. THE FEATURES OF DISEASE COURSE IN ADULTS

OBJECTIVE

The aim: To analyze the incidence of Hepatitis A in Ukraine and Poltava region and to study the clinical and epidemiological features of the course of Hepatitis A in adult patients.

PATIENTS AND METHODS

Materials and methods: The course of HA in 96 hospitalized patients was analyzed. The diagnosis of HA was established on the basis of clinical and epide¬miological data and confirmed by the results of laboratory studies (serological and molecular biological).

RESULTS

Results: In 2019, in the Poltava region, there was an increase in the incidence of Hepatitis A with a predominance among sick people of working age, among the urban population. This part of people aged from 60 to 75 years old constitutes 9.4%. This study showed that the waterway was the dominant way of HA transmission. The course of the disease in most hospitalized patients was typical and cyclic, with a predominance of a mixed variant of the pre-jaundice period and jaundice. One third of patients survey that they had fever, which persisted with jaundice.

CONCLUSION

Conclusions: The findings of this study indicates that the patients older than 40 years were more likely to have concomitant chronic pathology than younger patients, and Hepatitis A was more severe with the development of prolonged cholestasis, wave-like course and recurrence. In most patients under the age of 40, the course of Hepatitis A was mild, but splenomegaly and severe cytolytic syndrome were more common.

Atherosclerosis by Virus Infection—A Short Review

Atherosclerosis manifests by the thickening of artery walls and their narrowed channels through the accumulation of plaque. It is one of the most important indicators of cardiovascular disease. It can be caused by various factors, such as smoking, a high cholesterol diet, hypertension, hyperglycemia, and genetic factors. However, atherosclerosis can also develop due to infection. It has been reported that some bacteria and viruses can cause the development of atherosclerosis. Examples of these viruses are influenza viruses, herpes viruses, hepatitis viruses, or papillomaviruses, which are all prevalent and eminent globally for infecting the population worldwide. Moreover, many patients with coronavirus disease 2019 (COVID-19) showed symptoms of cardiovascular disease. In this review paper, the viruses linked to the development of atherosclerosis are introduced, and their viral characteristics, the mechanisms of the development of atherosclerosis, and the current vaccines and antiviral treatment methods are summarized.

Hepatitis Viruses Control Host Immune Responses by Modifying the Exosomal Biogenesis Pathway and Cargo

The development of smart immune evasion mechanisms is crucial for the establishment of acute and chronic viral hepatitis. Hepatitis is a major health problem worldwide arising from different causes, such as pathogens, metabolic disorders, and xenotoxins, with the five hepatitis viruses A, B, C, D, and E (HAV, HBV, HCV, HDV, and HEV) representing the majority of the cases. Most of the hepatitis viruses are considered enveloped. Recently, it was reported that the non-enveloped HAV and HEV are, in reality, quasi-enveloped viruses exploiting exosomal-like biogenesis mechanisms for budding. Regardless, all hepatitis viruses use exosomes to egress, regulate, and eventually escape from the host immune system, revealing another key function of exosomes apart from their recognised role in intercellular communication. This review will discuss how the hepatitis viruses exploit exosome biogenesis and transport capacity to establish successful infection and spread. Then, we will outline the contribution of exosomes in viral persistence and liver disease progression.

Dynamic Changes in Hepatitis A Immunity in Regions with Different Vaccination Strategies and Different Vaccination Coverage

The data on hepatitis A virus (HAV) seroprevalence are critical for the implementation of a universal mass vaccination (UMV) strategy. The latter has not been implemented in Russia; however, regional child vaccination programs have been adopted in some parts of the country. The aim of this study is to assess changes in HAV immunity within the last decade in regions of Russia with different vaccination strategies and different vaccination coverage rates. In regions where UMV has not been implemented and HAV vaccination coverage rates do not exceed the national average, the 50% seroprevalence threshold has shifted in the Moscow region from people aged under 40 years in 2008 to people aged over 59 years in 2020, and from people aged under 30 years to people aged over 40 years in the Khabarovsk region. In two regions (Yakutia and Sverdlovsk), a two-dose-based UMV scheme has been in place since 2011 and 2003, respectively, and in Tuva single-dose child immunization was launched in 2012. These regional programs have resulted in a significant increase in HAV seroprevalence in children and adolescents. In Yakutia, 50% herd immunity had been achieved by 2020 in age groups under 20 years, compared to 20−30% seroprevalence rates in 2008. In the Sverdlovsk region, HAV immunity has increased to >65% over the decade in children aged over 10 years, adolescents and young adults, whereas it declined in older age groups. However, a three-fold drop in HAV immunity has occurred in children under 10 years of age, reflecting a significant decline in vaccination coverage. In Tuva, HAV immunity rates in children under 10 years old increased two-fold to exceed 50% by 2020. These data suggest that UMV should be implemented on a national level. Measures to control vaccination coverage and catch-up vaccination campaigns are recommended in order to maintain the effectiveness of existing HAV vaccination programs.

Digestive Health in Sexual and Gender Minority Populations

It has been over 50 years since the Stonewall Inn Riots in June 1969, a seminal event for the lesbian, gay, bisexual, transgender, queer, intersex, and other sexual and gender-diverse minorities (LGBTQI+, or lesbian, gay, bisexual, transgender, queer, intersex, and everyone else) rights movement. However, sexual and gender minority (SGM) individuals still face discrimination and harassment due to their sexual orientation or gender identity. As such, the National Institute on Minority Health and Health Disparities has identified SGM communities as a "health disparity population." Broadly, there are higher rates of sexually transmitted infections, substance use and abuse, mental health conditions, obesity and eating disorders, certain cancers (breast, cervical, and anorectal), and cardiovascular disease in SGM communities. Transgender patients, especially those of color, are more likely to be uninsured, experience discrimination, and be denied health care than cisgender patients. In addition, SGM individuals have twice the risk of lifetime exposure to emotional, physical, and sexual trauma compared with heterosexuals. It is expected all these factors would negatively affect digestive health as well. This review summarizes the effects of social determinants of health and discrimination on health care access, highlights important digestive diseases to consider in the SGM population, and offers solutions to improve and prioritize the health of these communities. We aim to draw attention to SGM-specific issues that affect gastrointestinal health and spur research that is desperately lacking.

Pediatric acute viral hepatitis with atypical variants: Clinical dilemmas and natural history

Classical acute viral hepatitis (AVH) has an uncomplicated outcome. Acute liver failure has a grave prognosis. Atypical manifestations of AVH are a group of disorders that causes significant morbidity and dilemmas in children. These include prolonged cholestasis, relapsing hepatitis, ascitic form of AVH, late-onset hepatic failure (LOHF), intravascular hemolysis, and provoking an autoimmune trigger leading to autoimmune hepatitis. These entities cause significant liver dysfunction or worsening and are often difficult to differentiate from chronic liver disease (CLD). Ascitic form of AVH, LOHF, decompensated CLD and acute-on-chronic liver failure have significant overlapping features that need to be carefully dissected out. In many cases, only on long-term follow-up, these clinical entities can be separately identified. Intravascular hemolysis is usually caused by associated glucose-6-phosphate dehydrogenase deficiency. Rarely CLD such as Wilson disease and autoimmune hepatitis can also present with hemolysis in the initial presentation, which can mimic AVH with hemolysis. Identifying deviations from typical manifestations aid in avoiding unnecessary investigations, allowing focused therapy and alleviating anxiety.

Oligomers of hepatitis A virus (HAV) capsid protein VP1 generated in a heterologous expression system

Background

The quasi-enveloped picornavirus, Hepatitis A Virus (HAV), causes acute hepatitis in humans and infects approximately 1.5 million individuals a year, which does not include the asymptomatically infected population. Several severe outbreaks in developing nations in recent years have highlighted the reduction in HAV endemicity, which increases the risk of infections in the vulnerable population. The current HAV vaccines are based on growing wildtype or attenuated virus in cell culture, which raises the cost of production. For generation of cheaper, subunit vaccines or strategies for antibody-based diagnostics, production of viral structural proteins in recombinant form in easily accessible expression systems is a priority.

Results

We attempted several strategies for recombinant production of one of the major capsid proteins VP1, from HAV, in the E. coli expression system. Several efforts resulted in the formation of soluble aggregates or tight association of VP1 with the bacterial chaperone GroEL. Correctly folded VP1 was eventually generated in a discrete oligomeric form upon purification of the protein from inclusion bodies and refolding. The oligomers resemble oligomers of capsid proteins from other picornaviruses and appear to have the correct secondary and antigenic surface structure.

Conclusions

VP1 oligomers generated in the bacterial expression system can be utilized for understanding the molecular pathway of HAV capsid assembly and may also have potential biomedical usages in prevention and diagnostics of HAV infections.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12934-022-01780-x.

Viral Hepatitis, Cholesterol Metabolism, and Cholesterol-Lowering Natural Compounds

Hepatitis is defined as inflammation of the liver; it can be acute or chronic. In chronic cases, the prolonged inflammation gradually damages the liver, resulting in liver fibrosis, cirrhosis, and sometimes liver failure or cancer. Hepatitis is often caused by viral infections. The most common causes of viral hepatitis are the five hepatitis viruses—hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), and hepatitis E virus (HEV). While HAV and HEV rarely (or do not) cause chronic hepatitis, a considerable proportion of acute hepatitis cases caused by HBV (sometimes co-infected with HDV) and HCV infections become chronic. Thus, many medical researchers have focused on the treatment of HBV and HCV. It has been documented that host lipid metabolism, particularly cholesterol metabolism, is required for the hepatitis viral infection and life cycle. Thus, manipulating host cholesterol metabolism-related genes and proteins is a strategy used in fighting the viral infections. Efforts have been made to evaluate the efficacy of cholesterol-lowering drugs, particularly 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, in the treatment of hepatitis viral infections; promising results have been obtained. This review provides information on the relationships between hepatitis viruses and host cholesterol metabolism/homeostasis, as well as the discovery/development of cholesterol-lowering natural phytochemicals that could potentially be applied in the treatment of viral hepatitis.