Hepatitis A Virus Infection Research Articles

Age-Specific Seroprevalence of Hepatitis A Virus in Turkey Between 2000 and 2023: Systematic Review and Meta-Analysis

Background: Hepatitis A virus (HAV) is a leading cause of acute viral hepatitis and is primarily transmitted by the fecal–oral route. The clinical presentation and progression of the disease varies according to the age of the patient. Turkey is classified as a moderately endemic country, and HAV infection continues to be an important public health problem worldwide. Methods: In this study, a systematic meta-analysis was conducted to evaluate age-specific HAV seroprevalence rates in Turkey between 2000 and 2023. A comprehensive literature review identified 57 articles that met the inclusion criteria. The studies were assessed for quality, and seroprevalence rates were evaluated across four different age groups. Statistical analyses were performed using Comprehensive Meta-Analysis (CMA) software (CMAVersion 3.0) and SPSS (SPSS Statistics 25.0). Results: HAV seroprevalence rates were found to be 73.18% in the 0 < 5 age group and 90.90% in the >35 age group. The overall seroprevalence estimated using a random effects model was 64.5% (95% CI: 58.3–70). High heterogeneity was observed among the studies, and the prevalence estimates changed when low-quality studies were excluded. Conclusions: This meta-analysis suggests that the increasing trend in HAV IgG seroprevalence in Turkey, especially among young populations, is likely due to the vaccination program initiated in 2012. Furthermore, the heterogeneity observed among regions highlights the importance of regional public health strategies. Future studies should focus on providing more detailed data to evaluate the long-term effects of vaccination and to explain regional differences in HAV seroprevalence.

Application of sodium hypochlorite for human norovirus and hepatitis A virus inactivation in groundwater.

In this study, the effect of sodium hypochlorite (10-200 ppm of Cl2) on the inactivation of human norovirus (HuNV) GII.4 and hepatitis A virus (HAV) in groundwater was investigated using propidium monoazide (PMA)/reverse transcription quantitative real-time PCR (RT-qPCR). Initially, 4.00 log10 genome copies/μL of HuNV GII.4 or 5.50 log10 genome copies/μL of HAV were artificially inoculated in groundwater. The titers of HuNV GII.4 and HAV decreased significantly (P < 0.05) with increasing Cl2 concentrations. Groundwater was treated with 10, 30, 50, 100, 150, and 200 ppm of Cl2, and the viable HuNV GII.4 was significantly (P < 0.05) reduced to 3.28 (0.21-log reduction), 3.18 (0.31-log reduction), 3.01 (0.48 log reduction), 2.75 (0.74 log reduction), 2.54 (0.95 log reduction), and 2.34 (1.15 log reduction) log10 genome copies/μL, respectively. The viable HAV was also significantly (P < 0.05) reduced to 4.99 (0.23 log reduction), 4.76 (0.46 log reduction), 4.55 (0.67 log reduction), 4.21 (1.01-log reduction), 3.89 (1.33 log reduction), and 3.64 (1.58 log reduction) log10 genome copies/μL, respectively. The decimal reduction times (D values) (1-log10 genome reduction) of HuNV GII.4 and HAV infectivity in groundwater were predicted as 116.7 and 98.9 ppm of Cl2, respectively, using the first-order kinetics model (HuNV GII.4: y = -0.0054x + 3.3585, correlation coefficient (R2) = 0.97; HAV: y = -0.0091x + 5.0470, R2 = 0.97). The result specifically suggests that 150- to 200-ppm Cl2 can potentially be used for the inactivation of >1-log10 genome copy/μL HuNV GII.4 and HAV in groundwater.IMPORTANCEGroundwater represents a vital component of the global water supply, serving as a crucial source of potable water for humans. It serves as a source of potable water for up to 50% of the global population and accounts for 43% of all water used for irrigation. It thus follows that the sustainable management of groundwater represents a pivotal solution. However, the regrowth of pathogens in water that is not treated with chlorine or where proper residual chlorine is not maintained represents a risk to public health.

Seropositivity of hepatitis A and E viruses in patients attending a tertiary care center in central India

Objectives: Hepatitis A virus (HAV) and hepatitis E virus (HEV) infections are significant global health concerns that contribute to acute viral hepatitis. This study aimed to investigate the prevalence of HAV, HEV, and co-infections in a tertiary care hospital setting in central India. Materials and Methods: This retrospective observational study analyzed 987 clinical specimens collected from suspected acute viral hepatitis cases over 5 years (2019–2023). Commercially available enzyme-linked immunosorbent assay kits were used to detect HAV and HEV immunoglobulin M antibodies. Statistical analysis: Demographic data and clinical information were collected and analyzed using Chi-square tests. P &lt; 0.05 was considered statistically significant, indicating a significant association between the variables under investigation. Results: Overall, 32.72% of patients were seropositive for either HAV, HEV, or both. The prevalence of HAV was 22.9%, HEV was 9.83%, and co-infection was 3.24%. HAV infection was more prevalent in children (0–14 years), whereas HEV was more prevalent in adults. Both HAV and HEV infections were associated with elevated liver function markers, with the highest levels observed in co-infected cases. The monsoon season had the highest number of cases. Conclusions: This study revealed a substantial burden of HAV, HEV, and co-infections in central India. The observed sex—and age-specific prevalence patterns warrant further investigation. Effective public health strategies addressing sanitation, hygiene practices, and HAV vaccination programs are crucial to reducing the disease burden.

Establishment of enterically transmitted hepatitis virus animal models using lipid nanoparticle-based full-length viral genome RNA delivery system

BackgroundEnterically transmitted hepatitis viruses, such as hepatitis A virus (HAV) and hepatitis E virus (HEV), remain notable threats to public health. However, stable and reliable animal models of HAV and...

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

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. 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. 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. 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.

The Impact of Gender and Race on Outcomes for Hospitalized Hepatitis A Patients Stratified by Liver Disease Severity

BackgroundThe incidence of Hepatitis A Virus (HAV) infection is on the rise, with a minority of patients at risk for poor outcomes. This study investigates the prognostic impacts of race and gender on hospital outcomes among admitted HAV-infected patients. MethodsUsing the National Inpatient Sample from 2012-2017, patients admitted with HAV were selected and stratified by gender (Male and Female) and race (White, Black, Hispanic, Asian-Pacific Islander, Other). Propensity score-matching and statistical analysis was implemented with comparison to the controls (“Female” and “White”). Primary endpoints included mortality, length of stay (LOS), and hospitalization costs, while secondary endpoints consisted of hepatic-related medical complications such as ascites, hepatic encephalopathy, varices, and acute liver failure. ResultsFemales with compensated cirrhosis had increased odds of mortality (aOR 2.59, 95% CI 1.14-5.91, p=0.02). Otherwise, no other differences in mortality were detected between genders and races. Females had a shorter hospital LOS (aOR 0.97, 95% CI 0.96 - 0.98, p < 0.001), lower adjusted cost ($12,241 vs $13,510, aOR 0.92, 95% CI 0.92 - 0.92, p < 0.001), lower odds of esophageal varices (aOR 0.74, 95% CI 0.57 - 0.97, p = 0.03) and hepatic encephalopathy (aOR 0.67, 95% CI 0.53 - 0.84, p < 0.001) compared to males. Black patients exhibited higher LOS (aOR 1.06, 95% CI 1.04 - 1.08, p < 0.001) and adjusted costs ($13,392 vs $12,592, aOR 1.02, 95% CI 1.02 - 1.03, p < 0.001). Hispanic patients exhibited higher rates of esophageal varices (aOR 2.19, 95% CI 1.28-3.76, p = 0.005) and adjusted costs ($14,202 vs $12,381, aOR 1.07, 95% CI 1.07 - 1.07, p < 0.001), and Asian patients experienced higher adjusted costs ($18,426 vs $13,137, aOR 1.10, 95% CI 1.10-1.10, p < 0.001) compared to white patients. ConclusionVarious nuanced impacts of gender and race on hospitalization outcomes in HAV infection were observed, with only one subgroup analysis demonstrating a higher rate of mortality. Further research is warranted to better understand these findings and their implications.

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.

Prevalence of HAV IgM marker of Hepatitis A virus among patients of all Ages in Diyala province/Iraq

The most prevalent viral infection that causes hepatitis is hepatitis A virus (HAV), which continues to be a worldwide health issue for both developed and underdeveloped nations. By calculating the rate of HAV IgM positive, the current study sought to determine the prevalence of HAV infections among patients in the province of Diyala. In the present study, a total of 180 blood specimens were collected from patients, who referred to diagnostic individuals in Diyala Province, Iraq from October /2022 till Agust 2023. The presence of HAV in the specimens was investigated using ELISA technique. The results of the current study revealed that the overall positivity rate of HAV IgM was 13.3%. HAV IgM positivity was higher among 1-2 years old group. While, it was insignificantly higher among females compared to males (54.2%). Furthermore, HAV IgM positivity rate was insignificantly higher among Rurales compared to urbans (58.3%, 41.7%). Additionally the results showed that HAV IgM positivity rate among those used unsterilized water (70.8%) was significantly higher than that sterilized water (29.2%). Moreover, the results found that those with un vaccinated with HAV vaccine had significantly higher (79.2%) HAV IgM positivity rate. The present study founded that it is important to increase our knowledge about the frequency of HAV infections among patients and early diagnosis of HAV infections is essential in community for infection control.

A declining trend of hepatitis A and hepatitis E at tertiary care hospital in South Gujarat

Objectives: Hepatitis A virus (HAV) and Hepatitis E virus (HEV) both are spread through the fecal-oral route and cause acute viral hepatitis (AVH) and pose a major public health problem in India. This study was done to find out the proportion of positivity of HAV and HEV in patients with AVH and its seasonal trend. Materials and Methods: A retrospective study was carried out at Surat Municipal Institute of Medical Education and Research Medical College, Department of Microbiology, Surat, Gujarat. Result of 3615 blood samples of suspected AVH patients of the past 5 years (January 2018–December 2022) were taken from hospital data records. The enzyme-linked immunosorbent assay method was used to test serum samples for immunoglobulin M (IgM) HAV and IgM HEV antibodies for HAV and HEV, respectively. All samples were evaluated for liver function as well. Results: The positivity of HAV and HEV was 15.13% and 10.26%, respectively. The coinfection rate was 2.07%. HAV and HEV both affected males more than females. Among pregnant females, HEV infection had more positivity (6.77%) than HAV, which had 1.08% positivity. HAV and HEV infections had a seasonal trend, with the highest infection rate in the monsoon. Conclusion: The declining trend of cases of HAV and HEV was found in Surat city of south Gujarat which indicates increased awareness about hepatitis among people and better public health management by the civic authorities.

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.

Hepatitis A Virus Infection in Cynomolgus Monkeys Confounds the Safety Evaluation of a Drug Candidate.

In a 3-month toxicity study in cynomolgus monkeys at a European contract laboratory, animals were infected with HAV, initially resulting in hepatic injury being incorrectly attributed to the test compound. Elevated serum ALT/AST/GLDH (5- to 10-fold) were noted in individual animals from all groups including controls, with no apparent dose, exposure, or time-related relationship. Liver histopathology revealed minimal to slight inflammatory cell accumulation in periportal zones of most animals, and minimal to slight hepatocyte degeneration/necrosis in 10/42 animals from all groups. As these findings were more pronounced in 6 drug-treated animals, including 2/6 in the low dose group, the draft report concluded: "treatment-related hepatotoxicity at all dose levels precluded determination of a NOAEL." However, the unusual pattern of hepatotoxicity suggested a factor other than drug exposure might have caused the hepatic effects. Therefore, snap-frozen liver samples were tested for hepatitis viruses using a PCR method. Tests for hepatitis B, C, and E virus were negative; however, 20/42 samples were positive for hepatitis A virus (HAV). Infection was strongly associated with increased serum ALT/GLDH, and/or hepatocyte degeneration/necrosis. Re-evaluation of the study in light of these data concluded that the hepatic injury was not drug-related. A subsequent 6-month toxicology study in HAV-vaccinated cynomolgus monkeys confirmed the absence of hepatotoxicity. Identification of HAV infection supported progression of the drug candidate into later clinical trials. Although rarely investigated, subclinical HAV infection has occasionally been reported in laboratory primates, including those used for toxicology studies and it may be more prevalent than the literature indicates.

Presence of Enteric Viruses in Shellfish Samples from the Persian Gulf.

Shellfishes are a significant economic and nutritious seafood amongst people in different countries. Seafood products, particularly shellfish, are potential reservoirs of enteric viruses. This research investigated the incidence of rotavirus (RoV), norovirus (NoV) GI and GII, hepatitis A virus (HAV), and hepatitis E virus (HEV) in shellfish samples from the Persian Gulf, Iran. One hundred and fifty shellfish samples were collected. RNA extraction and cDNA synthesis were performed using commercial kits. The real-time polymerase chain reaction assessed the presence of enteric viruses in extracted cDNA samples. Thirty-two out of 150 (21.33%) shellfish samples were contaminated with enteric viruses. Prevalence rates of NoV GI, NoV GII, HAV, and RoV amongst shellfish samples were 8.00%, 11.33%, 1.33%, and 0.66%, respectively. There were no contaminated shellfish samples with HEV. Simultaneous prevalence of HAV and NoV GI, and HAV and NoV GII viruses were 0.66% and 0.66%, respectively. Examined viruses had a higher prevalence in shellfish samples collected in the winter season (P<0.05). Prevalence of HAV, RoV, NoV GI, and NoV GII amongst shellfish samples gathered in the winter season was 2.85%, 9.09%, 11.90%, and 20%, respectively. To the best of our knowledge, this was the first report of the incidence of enteric viruses, particularly HAV, NoV GI, NoV GII, and RoV, in shellfish samples from the Persian Gulf, Iran. Shellfish samples may serve as a potential source of enteric viruses for the human population. Therefore, routine viral assessments should be conducted. The consumption of fully cooked shellfish can significantly reduce the risk of HAV, RoV, NoV GI, and NoV GII infections. Furthermore, given the export value and importance of shellfish samples, their microbial quality and safety should be routinely monitored.

In-house RT-PCR detection of hepatitis A virus in human plasma pools used for the manufacture of medicinal products

Hepatitis A virus (HAV) is the most frequent cause of viral hepatitis worldwide and is transmitted through the fecal-oral route. However, HAV can also be transmitted by blood-derived products. This is due to the fact that viremia occurs during the asymptomatic phase of HAV infection, enabling infected blood or plasma donations to occur. Viral inactivation/removal steps are included during manufacturing of plasmaderived products. However, HAV is a small non-enveloped virus very difficult to remove with traditional viral inactivation procedures. To accomplish European guidelines for pooled human plasma (treated for virus inactivation), plasma manufacturers have been implementing HAV nucleic acid test (NAT) screening on plasma pools. In this study, we validate an in-house multiplex reverse-transcription real-time PCR (RT-PCR) assay targeting HAV RNA and an internal control with hydrolysis probes for amplicon detection. The HAV RNA test was validated by assessing limit of detection, robustness, sensitivity and specificity according to European Pharmacopoeia (Ph. Eur.) guidelines. Our assay is able to detect 100 IU/mL of all human HAV genotypes that have been described so far. The multiplex assay shows remarkable sensitivity with a 95% lower limit of detection of 5.2 IU/mL. Also, our HAV test shows good robustness, precision, and specificity. We conclude that our assay broadly meets the requirements for its purpose. The implementation of this test in the production process of plasma-derived products will increase their safety.

Fixing a Hole: a retrospective cohort study evaluating HAV, HBV, tetanus screening, and vaccination during hospitalization in persons who use substances.

Rates of serious injection-related infections in persons who use drugs have increased. Resulting admissions are an opportunity for screening and vaccination of preventable infections such as hepatitis A virus (HAV), hepatitis B virus (HBV), and tetanus. We conducted a retrospective review of adults with documented substance use admitted for bacterial infection between July 2015 and March 2020. We evaluated HAV, HBV, and tetanus vaccination status at admission, along with screening for HAV and HBV infection and immunity. We identified the proportion of patients at risk for infection who received HAV, HBV, and tetanus vaccines during admission and patient-level factors associated with vaccination. We identified 280 patients who met our inclusion criteria. Of the 198 (70.7%) patients at risk for HAV, infectious disease providers recommended vaccination for 21 (10.6%) and 15 (7.6%) received HAV vaccine. Of the 174 (62.1%) patients at risk for HBV, infectious disease providers recommended vaccination for 32 (18.3%) and 25 (14.4%) received HBV vaccine. A large proportion of patients (31.4%, 88) had no documentation of prior tetanus vaccination, and infectious disease providers recommended tetanus vaccination for three (1.1%) and five patients (1.8%) received a tetanus booster. Infectious disease consult vaccine recommendations were statistically significantly associated with HAV or HBV vaccination prior to discharge. Over 70% of our population is at risk for one or more of these preventable infections. Efforts are needed to maximize inpatient screening and vaccination for HAV, HBV, and tetanus in patients with barriers to care.

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.

Trends in seroprevalence of enteric transmitted hepatitis virus infections at a tertiary care hospital in Delhi: a 4-year review

Background: Hepatitis A virus (HAV) and hepatitis E virus (HEV), both enteric hepatitis viruses, are transmitted through the feco-oral route. These infections can range from asymptomatic or subclinical cases to acute viral hepatitis, occasionally leading to mortality. To gain an understanding of the disease and develop effective management strategies, comprehending the disease burden is essential. This study aimed to provide insights into the prevalence of enteric transmitted hepatitis viruses among individuals with acute hepatitis in the Delhi region. Methods: A retrospective investigation was conducted at a prominent tertiary care super specialty hospital in Delhi, spanning from February 2019 to December 2022. Serum samples from patients suspected of having hepatitis and sent for HAV and HEV testing were included. The samples underwent enzyme-linked immunosorbent assay to detect HAV and HEV immunoglobulin (Ig)M antibodies. Collected data was analyzed using SPSS software version 21, employing Chi-square and Fischer exact tests where applicable. Results: Throughout the study period, a total of 1275 samples were incorporated. Viral etiology was evident in 197 patients (15.45%). Among these, IgM HAV was identified in 142 patients (11.13%), and IgM HEV was present in 55 patients (4.31%). HAV infection was notably more prevalent in the pediatric age group (20.89% or 89/426; p&lt;0.001), while HEV was significantly more common among adolescents and adults (5.77% or 49/849; p&lt;0.001). Conclusions: Regular surveillance of enteric transmitted viruses causing hepatitis should encompass both hospital and community levels to accurately gauge disease burden and evolving epidemiology.

Immune Thrombocytopenic Purpura: An uncommon manifestation of Hepatitis A with acute liver failure

&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; Hepatitis A Virus (HAV) infection is a benign, self-limited gastrointestinal infection of children. Autoimmune hematological manifestation is very rare in children. Here, we report an 11-year-old male child having HAV infection with acute liver failure, complicated with persistent thrombocytopenia and haematuria during the course of illness and eventually diagnosed as a case of HAV infection associated with immune thrombocytopenic purpura. The child was treated successfully with a short course of steroid therapy.&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D;

Prevalence of Rotavirus, Adenovirus, and Hepatitis A Virus in a Tertiary Care Hospital in Somalia

Rotavirus, one of the viral infectious agents that is transmitted mainly through the fecal-oral route and spreads easily in regions with poor sanitation conditions, is the most common causative agent of acute gastroenteritis in children under five years of age worldwide, and enteric adenoviruses are other frequently encountered causative agents of gastroenteritis in childhood. Hepatitis A virus (HAV) is also transmitted in similar routes and is endemic in regions with poor sanitation conditions and limited access to clean water and is usually acquired in early childhood in these regions. In this study conducted in Mogadishu Somalia, rotavirus and adenovirus antigen test (immunochromatographic rapid test) results in patients admitted to a tertiary hospital in the 9-month period between February 2019 and October 2019 and ELISA based HAV antibody test results studied in 2018-2019 were retrospectively examined and it was aimed to determine the distribution of positivity rates of these viruses by age, gender, and year. During the study period, 1136 patients (mean age 6.33±12.36) were tested for rotavirus and adenovirus antigens, and 362 patients (mean age 21.26±18.45) were tested for anti-HAV IgM/IgG antibodies. The positivity rates of rotavirus and adenovirus were found as 17.8% and 5.1%, respectively. The positivity rates of anti-HAV IgM and IgG antibodies were 26.5% and 85.4%. The age group with the highest rotavirus test positivity was babies under one year old (27.3%), positivity rate was also high in children aged 1-2 years old (20.9%), and this distribution was similar for adenovirus. Although a small number of patients were tested in under five years of age, anti-HAV IgG seropositivity was 60% and above in all age groups. The highest anti-HAV IgM positivity rates were observed in children 2-&lt;5 and 5-15 years of age, 52.9% and 44% respectively. Rotavirus antigen positivity was found at high levels in the three-month period covering June, July, and August 2019. In July (2019), it was observed that the number of rotavirus and adenovirus antigen test requests were increased, and also, at the same time the highest positivity rates for both viruses were observed; 31.2% and 9.5% for rotavirus and adenovirus. Rotavirus and enteric adenovirus co-infection was detected in 2.4% (27/1136) of the patients, and 23 (85.2%) of these were under five years of age children. Our study results show that children under the age of two are especially affected by rotavirus and adenovirus infections in Somalia and indicate that HAV infections are acquired at an early childhood. We can say that it may be useful to review vaccination programs as an important public health measure to reduce the burden of mortality and morbidity associated with HAV and rotavirus, which have a high prevalence and also have protective vaccines.

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 antibodiesproduced 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.

Determining Herd Immunity Thresholds for Hepatitis A Virus Transmission to Inform Vaccination Strategies Among People Who Inject Drugs in 16 US States.

Widespread outbreaks of person-to-person transmitted hepatitis A virus (HAV), particularly among people who inject drugs (PWID), continue across the United States and globally. However, the herd immunity threshold and vaccination coverage required to prevent outbreaks are unknown. We used surveillance data and dynamic modeling to estimate herd immunity thresholds among PWID in 16 US states. We used a previously published dynamic model of HAV transmission calibrated to surveillance data from outbreaks involving PWID in 16 states. Using state-level calibrated models, we estimated the basic reproduction number (R0) and herd immunity threshold for PWID in each state. We performed a meta-analysis of herd immunity thresholds to determine the critical vaccination coverage required to prevent most HAV outbreaks among PWID. Estimates of R0 for HAV infection ranged from 2.2 (95% confidence interval [CI], 1.9-2.5) for North Carolina to 5.0 (95% CI, 4.5-5.6) for West Virginia. Corresponding herd immunity thresholds ranged from 55% (95% CI, 47%-61%) for North Carolina to 80% (95% CI, 78%-82%) for West Virginia. Based on the meta-analysis, we estimated a pooled herd immunity threshold of 64% (95% CI, 61%-68%; 90% prediction interval, 52%-76%) among PWID. Using the prediction interval upper bound (76%) and assuming 95% vaccine efficacy, we estimated that vaccination coverage of 80% could prevent most HAV outbreaks. Hepatitis A vaccination programs in the United States may need to achieve vaccination coverage of at least 80% among PWID in order to prevent most HAV outbreaks among this population.