Healthcare resource utilization and costs associated with hepatitis A in the United States: a retrospective database analysis.

Aim. To investigate hepatitis A-related healthcare resource use and costs in the US.Methods. The Merative Marketscan Commercial Claims and Encounters database was retrospectively analyzed for hepatitis A-related inpatient, outpatient, and emergency department (ED) claims from January 01, 2012 to December 31, 2018. We calculated the hepatitis A incidence proportion per 100,000 enrollees, healthcare resource utilization, and costs (in 2020 USD). Results were stratified by age, gender, and select comorbidities.Results. The overall hepatitis A incidence proportion was 6.1 per 100,000 enrollees. Among individuals with ≥1 hepatitis A-related claim, the majority (92.6%) had ≥1 outpatient visit related to hepatitis A; 9.1% were hospitalized, and 4.2% had ≥1 ED visit. The mean (standard deviation [SD]) length of hospital stay was 5.2 (8.1) days; the mean (SD) number of outpatient and ED visits were 1.3 (1.3) and 1.1 (0.6), respectively. The incidence proportion per 100,000 was higher among adults than children (7.5 vs. 1.5), individuals with HIV than those without (126.7 vs. 5.9), and individuals with chronic liver disease than those without (143.6 vs. 3.8). The total mean (SD)/median (IQR) per-patient cost for hepatitis A-related care was $2,520 ($10,899)/$156 ($74-$529) with the mean cost of hospitalization was 18.7 times higher than that of outpatient care ($17,373 vs. $928).Limitations. The study data included only a commercially insured population and may not be representative of all individuals.Conclusions. In conclusion, hepatitis A is associated with a substantial economic burden among privately insured individuals in the US.

Hepatitis A is an acute liver infection caused by the hepatitis A virus. In the US, safe and effective vaccines for hepatitis A have been available since 1996. Vaccination recommendations include children (all children aged 12 to 23 months and previously unvaccinated children 2 to 18 years of age) and adults at risk of infection or severe disease (e.g., international travelers, men who have sex with men, people experiencing homelessness, those with chronic liver disease or HIV). Since 2016, the US has experienced person-to-person outbreaks of hepatitis A, primarily affecting unvaccinated individuals who use drugs or are experiencing homelessness. To better understand the impact of hepatitis A in the US, we assessed healthcare resource use and costs in patients with hepatitis A from 2012 to 2018, including 15,435 individuals with a hepatitis A-related insurance claim in the Merative Marketscan Commercial Claims and Encounters database. We found that slightly more than 6 per 100,000 enrollees had hepatitis A from 2012 to 2018 and the number of people treated for hepatitis A per 100,000 was highest for people living with HIV or chronic liver disease. The majority (92.6%) of people reported at least an outpatient visit, 9.1% were hospitalized, and 4.2% had an emergency department visit. The average cost for hepatitis A-related care was $2,520 per patient and was 18.7 times higher for hospitalized patients ($17,373) than for patients treated in outpatient care ($928). Our results are limited by the generalizability of the dataset, which is a convenience sample of private insurance claims, and unlikely to capture groups at high-risk for hepatitis A, such as individuals experiencing homelessness. In conclusion, hepatitis A leads to considerable healthcare costs for privately insured individuals in the US.

Safety and 6-month immune persistence of inactivated poliovirus vaccine (Sabin strains) simultaneously administrated with other vaccines for primary and booster immunization in Jiangxi Province, China.

OBJECTIVES: This study aims to evaluate the safety of a new inactivated poliomyelitis vaccine (Sabin strains) (sIPV) for large-scale use in primary and booster immunizations, whether simultaneously administered with other vaccines or not and to explore the persistence of all vaccines at approximately six months after vaccination. METHOD: A total of 3200 infants were recruited into this study, including 2000 infants aged 2-3 months randomly assigned (1:1) into the "sIPV basic" or the "sIPV+DTaP" group for primary immunization of sIPV. Another 1200 children aged 18 months old and above were randomly assigned (2:2:1:1) into the "sIPV booster," "sIPV+HepA-I," "sIPV+MMR", or "sIPV+HepA-L" group for booster immunization of sIPV. Adverse events within 30 days of each vaccination dose in all participants were self-reported by guardians using a WeChat mini-program. Approximately 200 blood samples were collected at 5-7 months after the final vaccination to test for antibodies against poliovirus and other viruses. RESULTS: 3198 participants in total were included in the safety study, including 1999 infants aged 2-3 months old and 1199 children aged 18-26 months old. For primary immunization, the incidence of adverse reactions in the "sIPV basic" and the "sIPV+DTaP" group were 3.19 and 6.21% (P = 0.001), respectively. For booster immunization, the incidences of adverse reaction for the "sIPV booster" group were 2.25%, while the incidence for the "sIPV +others" group in total was 2.50% (P = 0.788). Most adverse reactions were mild. Fever was the most common symptom in all groups. No vaccine-related serious adverse events (SAEs) were observed in this study. The seropositivity rates of antibodies in the "sIPV basic" and the "sIPV+DTaP" group were 92.31 and 100% against type 1 poliovirus (P = 0.031); 96.15% and 98.57% against type 2 poliovirus (P = 0.575); 98.08% and 91.43% against type 3 poliovirus (P = 0.237), respectively. Regarding booster vaccination with sIPV, whether co-administered with other vaccines or not, the seropositivity rates of antibodies against the three types of polioviruses were all 100%. Seropositivity rates of antibodies against hepatitis A, measles, mumps, and rubella were all no <77%, except for pertussis, which was <30%. CONCLUSION: sIPV demonstrated good safety and immune persistence for primary and booster vaccinations, whether administered singly or simultaneously. Antibodies against hepatitis A, measles, mumps and rubella were not disrupted by the co-vaccination. However, the seropositivity rates and geometric mean concentrations (GMCs) of antibodies against pertussis indicate the necessity for a booster dose.

Development of the first officially licensed live attenuated duck hepatitis A virus type 3 vaccine strain HB80 in China and its protective efficacy against DHAV-3 infection in ducks.

Duck hepatitis A virus type 3 (DHAV-3) is an infectious virus that is highly fatal to ducklings and causes significant economic losses in the duck industry worldwide. Biosecurity and vaccination are required to control the pathogen. In the present study, we attenuated a lowly pathogenic DHAV-3 clinical isolate, named as HB, by serial passaging in duck embryos, and followed by several adaptive proliferations in specific-pathogen-free (SPF) chicken embryos. The virulence of DHAV-3 at different passages was assessed by infecting 3-day-old ducklings. We found that the HB strain lost pathogenicity to ducklings from the 55th passage onwards. The 80th passage strain (HB80), which achieved good growth capacity in duck embryos with a viral titer of 108.17 50% egg lethal dose per milliliter (ELD50/mL), was selected as a live attenuated vaccine candidate. The HB80 strain did not induce clinical symptoms or pathological lesions in 3-day-old ducklings and showed no virulence reversion after 5 rounds of in vivo back-passage. The minimum effective dose of HB80 was determined to be 104.5 ELD50 by hypodermic inoculation of the neck. Importantly, a single dose of HB80 elicited good immune responses and provided complete protection against challenge with the lethal DHAV-3 strain. Compared with the genomic sequence of the parental HB strain, HB80 had 7 amino acid substitutions, two of them are in the hypervariable region of the VP1 and polymerase-encoding 3D regions, which may play a role in virulence attenuation. Our data suggest that the attenuated HB80 strain is a promising vaccine candidate for the prevention of DHAV-3 infections in China. HB80 has been registered as a New Veterinary Drug Registration Certificate by the Chinese Ministry of Agriculture and Rural Affairs (MARA), and is the first live attenuated DHAV-3 vaccine strain to be officially licensed in China.

Factors Associated With Hepatitis A Seropositivity at 23 Years After Childhood Vaccination.

We evaluated factors associated with the presence of hepatitis A virus antibodies 23 years after initiating vaccination at ages 6-15 months. Among 67 participants, 86% (42/49) of those vaccinated at ages 12-15 months and 61% (11/18) of those vaccinated at 6 months remained seropositive at 23 years. Lack of maternal antibodies at enrollment and higher initial vaccine response were independently associated with higher antibody concentrations at 23 years. Further research is needed to assess the duration of hepatitis A vaccine protection and possible need for a booster dose.

Concurrently Affected by Dengue and Hepatitis A: Exploring the Intricacies of Co-infection in a Comprehensive Case Series.

Based on the examination of four distinct cases, this case series offers a thorough investigation of the intricate relationship between dengue fever and hepatitis A infection. Despite their distinct origins, both illnesses manifest overlapping clinical features, posing considerable diagnostic hurdles, particularly in endemic regions. The cases reveal consistent symptoms such as elevated fever, abdominal discomfort, jaundice, and irregular liver function test results, underscoring the intricate nature of an accurate diagnosis. Variations in age distribution and the severity of symptoms underscore the necessity for tailored treatment approaches. Diagnostic challenges stem from the similarity in clinical presentations and shared laboratory abnormalities, necessitating comprehensive serological assessments. Therapeutic strategies entail a multidisciplinary approach addressing both hepatic and systemic manifestations, with supportive measures ensuring favorable clinical outcomes. Despite the complexities involved, timely interventions facilitate gradual symptom amelioration and successful patient recovery. Informing clinical practice and directing public health actions, this case series provides insightful information about the diagnostic and treatment complications associated with co-occurring dengue fever and hepatitis A infection.

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.

Prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency among the fulminant hepatitis A virus infection patients.

Background: Hepatitis A is a widespread viral infection with significant public health implications. Assessing glucose 6-phosphate dehydrogenase (G6PD) deficiency in hepatitis A patients is essential for various reasons, including prognosis, disease severity evaluation, encephalopathy risk identification, tailored management, and advancing scientific understanding. This study aimed to investigate the prevalence and clinical implications of G6PD impairment in individuals with fulminant hepatitis A. Methods: A cross-sectional descriptive analysis was conducted, involving hospitalized patients with fulminant hepatitis A. Demographic data, prevalence rates, and clinical findings were recorded in a database. The diagnosis of hepatitis A infection was confirmed using an anti-HAV IgM antibody test, and G6PD enzyme activity was measured with a fluorescent spot assay. Results: Out of 81 patients with hepatitis A, 57 (70.4%) were males, and 24 (29.5%) were females, with an average age of 24.6 years. Dark yellow urine and anorexia were the most common clinical symptoms. Notably, 30 (37%) patients lacked G6PD. The group with G6PD deficiency showed significantly higher rates of encephalopathy and mortality (P<0.01), along with elevated bilirubin (P=0.00), abnormal coagulation parameters, and low hemoglobin levels (P=0.00). Conclusion: In light of these findings, the present study proposes the implementation of routine G6PD level assessments and the evaluation of other relevant markers in regions where hepatitis A is endemic. Furthermore, the study underscores the need for vigilant monitoring of hemolysis and encephalopathy in affected patients to optimize clinical management and reduce morbidity and mortality associated with this condition.

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.

Reconstruction of the historic time course of blood-borne virus contamination of clotting factor concentrates, 1974-1992.

Factor VIII and IX clotting factor concentrates manufactured from pooled plasma have been identified as potent sources of virus infection in persons with hemophilia (PWHs) in the 1970s and 1980s. To investigate the range and diversity of viruses over this period, we analysed 24 clotting factor concentrates for several blood-borne viruses. Nucleic acid was extracted from 14 commercially produced clotting factors and 10 from nonremunerated donors, preserved in lyophilized form (expiry dates: 1974-1992). Clotting factors were tested by commercial and in-house quantitative PCRs for blood-borne viruses hepatitis A, B, C and E viruses (HAV, HBV, HCV, HEV), HIV- types 1/2, parvoviruses B19V and PARV4, and human pegiviruses types 1 and 2 (HPgV-1,-2). HCV and HPgV-1 were the most frequently detected viruses (both 14/24 tested) primarily in commercial clotting factors, with frequently extremely high viral loads in the late 1970s-1985 and a diverse range of HCV genotypes. Detection frequencies sharply declined following introduction of virus inactivation. HIV-1, HBV, and HAV were less frequently detected (3/24, 1/24, and 1/24 respectively); none were positive for HEV. Contrastingly, B19V and PARV4 were detected throughout the study period, even after introduction of dry heat treatment, consistent with ongoing documented transmission to PWHs into the early 1990s. While hemophilia treatment is now largely based on recombinant factor VIII/IX in the UK and elsewhere, the comprehensive screen of historical plasma-derived clotting factors reveals extensive exposure of PWHs to blood-borne viruses throughout 1970s-early 1990s, and the epidemiological and manufacturing parameters that influenced clotting factor contamination.

Comparison of Anti-Hepatitis A Antibody Pharmacokinetics in Healthy Australian Subjects Receiving Standard or Weight-Based Dosing of Polyvalent Immunoglobulin.

This randomized controlled trial compared two dosing regimens of the polyvalent immunoglobulin available for hepatitis A post-exposure prophylaxis in Australia. Participants were randomized to receive either 270 IU (standard dose) or 3.375 IU/kg (dose by weight). Quantitative serial serum hepatitis A antibody concentrations were measured at baseline and then on days 1, 3, 7, 28, and 50. Fifteen participants completed the trial. Serum hepatitis A antibody concentrations were not different between the study groups at any time point. Pharmacokinetic parameters estimated from participant data were not different between the study groups. The hepatitis A antibody level of all participants exceeded 10 mIU/mL at day 50. While no difference between dosing regimens was found in this study, further research should examine dosing at the lower limit of current Australian recommendations before making policy decisions.

Surface Display of Duck Hepatitis A Virus Type 1 VP1 Protein on Bacillus subtilis Spores Elicits Specific Systemic and Mucosal Immune Responses on Mice.

Duck viral hepatitis, primarily caused by duck hepatitis A virus type 1 (DHAV-1), poses a significant threat to the global duck industry. Bacillus subtilis is commonly utilized as a safe probiotic in the development of mucosal vaccines. In this study, a recombinant strain of B. subtilis, designated as B. subtilis RV, was constructed to display the DHAV-1 capsid protein VP1 on its spore surface using the outer coat protein B as an anchoring agent. The immunogenicity of this recombinant strain was evaluated in a mouse model through mixed feeding immunization. The results indicated that B. subtilis RV could elicit specific systemic and mucosal immune responses in mice, as evidenced by the high levels of serum IgG, intestinal secretory IgA, and potent virus-neutralizing antibodies produced. Furthermore, the recombinant strain significantly upregulated the expression levels of IL-2, IL-6, IL-10, TNF-α, and IFN-γ in the intestinal mucosa. Thus, the recombinant strain maintained the balance of the Th1/Th2 immune response and demonstrated an excellent mucosal immune adjuvant function. In summary, this study suggests that B. subtilis RV can be a novel alternative for effectively controlling DHAV-1 infection as a vaccine-based feed additive.

Designing the fusion protein of rotavirus VP8 and hepatitis A virus VP1 and evaluating the immunological response in BALB/c mice.

Background and Objectives: Rotavirus and Hepatitis A virus are responsible for causing gastroenteritis and jaundice. The current vaccination approaches have proven insufficient, especially in low-income countries. In this study, we presented a novel dual-vaccine candidate that combines the rotavirus VP8 protein and the hepatitis A virus VP1. Materials and Methods: The VP8*-rotavirus+AAY+HAV-VP1 fusion protein was produced using an Escherichia coli expression system. The recombinant protein had a molecular weight of approximately 45.5 kDa and was purified through affinity chromatography. BALB/c mice were injected subcutaneously with the recombinant protein, VP1, VP8 and vaccines for rotavirus and hepatitis A virus, both with and without ALUM and M720 adjuvants. ELISA assays were used to measure total IgG, IgG1, IgG2, and short-term and long-term IL-5 and IFN-γ responses. Results: The fusion protein, when combined with adjuvants, elicited significantly higher total IgG, IgG1, and IgG2 responses compared to VP1 and VP8 alone, as well as the rotavirus and hepatitis A vaccines. Furthermore, it induced a higher short-term IL-5 and IFN-γ response while demonstrating a higher long-term IL-5 response compared to the rotavirus and hepatitis A vaccines. Conclusion: This study demonstrates that the VP8*-rotavirus+AAY+HAV-VP1 fusion protein is a promising dual vaccine candidate for immunization against hepatitis A and rotaviruses.

Effectiveness of a Counseling Intervention to Increase Vaccination Uptake among Men Who Have Sex with Men during the Mpox Outbreak.

Men who have sex with men (MSM) are disproportionately impacted by sexually transmitted infections (STIs), including HIV and those preventable through vaccination such as mpox, HPV, HAV, and HBV. A retrospective cohort study was conducted to evaluate the effectiveness of counseling provided during mpox vaccination on the uptake of other recommended vaccines (HPV, HAV, and HBV) and to identify associated factors. Relevant covariates such as nationality, age, HIV status, and use of PrEP were retrieved from electronic medical records. Vaccination status data were retrieved from the regional vaccination registry. Of the 330 participants, 98.8% were males and the mean age was 40.6 years (SD: 11.2). Following consultation, a statistically significant increase for both HPV (from 25.8% to 39.1%) and HAV (from 26.7% to 36.1%) was observed (p < 0.001). The multivariate analysis showed a significant negative association between the uptake of HPV and HBV vaccines and foreign nationality (aOR 0.25 (95%CI 0.08-0.69), p = 0.012; and aOR 0.31 (95%CI 0.11-0.81), p = 0.021). The HBV vaccine uptake was negatively associated with increasing age. Our results suggest that tailored counseling can effectively bridge the gap in vaccine acceptance among vulnerable populations, thereby improving overall public health outcomes.

Therapeutic plasma exchange provides native liver survival benefit in children with acute liver failure: A propensity score-matched analysis.

OBJECTIVES: This study aimed to evaluate the safety and efficacy of therapeutic plasma exchange (TPE) in pediatric acute liver failure (PALF). METHODS: All children aged 2-18 years with PALF were included. The intervention cohort included a subset of PALF patients undergoing complete three sessions of TPE, whereas the matching controls were derived by propensity score matching from the patient cohort who did not receive any TPE. Propensity matching was performed based on the international normalized ratio (INR), grade of hepatic encephalopathy (HE), age, bilirubin, and ammonia levels. The primary outcome measure was native liver survival (NLS) in the two arms on day 28. RESULTS: Of the total cohort of 403 patients with PALF, 65 patients who received TPE and 65 propensity-matched controls were included in analysis. The 2 groups were well balanced with comparable baseline parameters. On day 4, patients in the TPE group had significantly lower INR (P = 0.001), lower bilirubin (P = 0.008), and higher mean arterial pressure (MAP) (P = 0.033) than controls. The NLS was 46.15% in the TPE arm and 26.15% in the control arm. The overall survival (OS) was 50.8% in the TPE arm and 35.4% in the control arm. Kaplan-Meier survival analysis showed a significantly higher NLS in patients receiving TPE than controls (P = 0.001). On subgroup analysis, NLS benefit was predominantly seen in hepatitis A-related and indeterminate PALF. CONCLUSION: TPE improved NLS and OS in a propensity-matched cohort of patients with PALF. Patients receiving TPE had lower INR and bilirubin levels and higher MAP on day 4.

Beyond the Liver: Unveiling Rhabdomyolysis as a Rare Complication of Hepatitis A.

Hepatitis A is a mild self-limiting infection of the liver with spontaneous resolution of symptoms in most cases. However, clinicians should be aware of some commonly encountered complications and extrahepatic manifestations associated with hepatitis A for timely diagnosis and treatment. Rhabdomyolysis, an exceedingly rare complication of hepatitis A, is scarcely documented. We present a case of a 64-year-old man with symptoms consistent with rhabdomyolysis and an evanescent rash secondary to acute hepatitis A. He eventually recovered with conservative management. This case emphasizes the importance of recognizing and treating atypical presentations of acute hepatitis A infection. LEARNING POINTS: Recognition of atypical presentations: The case underscores the importance of recognizing and treating atypical presentations of acute hepatitis A infection. Clinicians should be vigilant for unusual manifestations of common infections, facilitating timely diagnosis and appropriate management.Understanding rare complications: Rhabdomyolysis is identified as an exceedingly rare complication of hepatitis A infection, which is scarcely documented in the literature. This case contributes to the growing understanding of extrahepatic manifestations associated with hepatitis A, emphasizing the importance of considering uncommon complications in the differential diagnosis, especially when typical clinical presentations are observed.Management strategies: The article discusses the treatment approach for rhabdomyolysis secondary to acute hepatitis A, which involves aggressive fluid resuscitation to prevent kidney damage from myoglobinuria, correction of electrolyte imbalances, and metabolic abnormalities. Additionally, vaccination against hepatitis A and advocating for sanitation measures are highlighted as important preventive strategies.

Toxic epidermal necrolysis caused by viral hepatitis A: a case report and literature review.

Toxic epidermal necrolysis (TEN) is a rare but serious immune-mediated life-threatening skin and mucous membrane reaction that is mainly caused by drugs, infections, vaccines, and malignant tumors. A 74-year-old woman presented with a moderate fever of unknown cause, which was relieved after 2 days, but with weakness and decreased appetite. Red maculopapules appeared successively on the neck, trunk, and limbs, expanding gradually, forming herpes and fusion, containing a yellow turbidous liquid and rupturing to reveal a bright red erosive surface spreading around the eyes and mouth. The affected body surface area was >90%. The severity of illness score for toxic epidermal necrolysis was 2 points. The drug eruption area and severity index score was 77. She was diagnosed with TEN caused by hepatitis A virus and treated with 160 mg/day methylprednisolone, 300 mg/day cyclosporine, and 20 g/day gammaglobulin. Her skin showed improvements after 3 days of treatment and returned to nearly normal after 1 month, and liver function was completely normal after 2 months.

Rising trend of symptomatic infections due to Hepatitis A virus infection in adolescent and adult age group: An observational study from a tertiary care liver institute in India.

BACKGROUND: Hepatitis A Virus (HAV) is the most common cause of Acute Viral Hepatitis (AVH) in children. It causes self-limiting illness and rarely acute liver failure. The shifting pattern in HAV endemicity is rendering adolescents and adults vulnerable to infection. METHODS: In this retrospective study, samples received from 14,807 patients with acute onset icteric illness from January 2014-December 2022 were analyzed. HAV infection was detected by anti-HAV IgM positivity. The cases were divided into 3 age groups, pediatric, adolescents and adults, and clinical presentations were compared. RESULTS: Overall, 7.72%(1144) were positive for anti-HAV IgM. Of these, 60%(690) were finally included in the study. The positive cases were divided into adults, ≥18 years (44%, 304); pediatric, <12 years (31%, 212) and adolescents (25%,174) age groups. Overall males were predominant [72.4%(500)], with a median age of 16 (IQR:9-21) years. Cases were characterised into AVH (68.1%, 470/690), Acute Liver Failure (ALF) (31.4%, 217/690) and Acute-on-Chronic Liver Failure (0.43%, 3/690). AVH in the pediatric age group was 69%(146/212), adolescents was 67%(117/174), and adults was 68%(207/304). ALF cases among the 3 groups were 30%(65/212), 33%(57/174), and 31%(95/304) respectively. Overall mortality was seen in 6.52%(45/690), maximum in adolescents with ALF presentation [10.3%(18/174)]. On molecular characterization of infection, viremia was seen in 28.9%(200/690) and all the isolates were Genotype IIIA. CONCLUSIONS: The number of adults experiencing symptomatic HAV infection was seen to increase over the years in the present study. Infection in adolescents was associated with higher mortality and ALF as the clinical presentation.

Detection of Foodborne RNA Viruses by Reverse Transcriptase Droplet Digital PCR.

Foodborne viruses remain the largest cause of human gastroenteritis and one of the largest contributors to foodborne illnesses worldwide. Currently, quantitative reverse transcription PCR (qRT-PCR) or real-time qPCR are the detection methods commonly used for quantification of foodborne viruses, but those methods have several disadvantages, such as relying on standard curves for quantification and the background noise from a bulk reaction. ddPCR uses an oil-water emulsion to form multiple droplets that partition small amounts of viral genetic material (DNA or RNA) into each of the droplets. These droplets then undergo amplification cycles and are analyzed using Poisson distributions. This allows for absolute quantification without the need for a standard curve, which makes ddPCR a precise tool in surveillance of foodborne viruses. Herein, we describe the process of detecting foodborne viruses using RNA isolated from various matrices. Up to 96 samples including the positive and negative controls can be analyzed on a single plate by ddPCR.

Seroprevalence of hepatitis A virus among people born before and after implementation of universal vaccination in Argentina.

BACKGROUND: Until 2005, when a single dose of vaccine was implemented in one-year-old children, the Hepatitis A virus (HAV) was responsible for approximately 90% of acute hepatitis cases in the paediatric population in Argentina. However, despite vaccination success, sporadic outbreaks of HAV still occur among adults. This study aimed to assess the seroepidemiology of HAV in Argentina, analysing IgG and IgM antibodies against HAV in a large population, both vaccinated and unvaccinated. METHODS: The study included 16,982 patients attending a hospital from 2001 to 2023. The cohort was divided into two groups: 16,638 individuals who were not reached by the vaccination program implemented in 2005 and 344 children who were covered by the universal vaccination. RESULTS: Anti-HAV IgG was detected in 56.7% of cases. The rate was significantly higher in individuals born after 2005 (77.7%) compared to those born before (56.3%), p < 0.001. The age groups 19-40 and 41-60 years showed the anti-HAV IgG lowest rates. On the other hand, 100/3956 cases (2.5%) with suspected acute hepatitis were positive for Anti-HAVIgM. Notably, none of these were born after the mandatory vaccine rollout. CONCLUSIONS: The study of this large cohort contributes to the understanding of the seroepidemiology of HAV. Although the implementation of the vaccine achieved its main goal, the age segment between 19 and 60 years does not reach the estimated threshold to achieve herd immunity. These findings reveal the importance of targeting vaccination campaigns, provide essential insights for public health planning, and guide future immunisation strategies against HAV in Argentina.

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.