anti-HAV IgG Research Articles

A-258 Hepatitis A infections among patients suspected of acute hepatitis attended in Brazilian health services

Abstract Background Millions of people worldwide are infected with Hepatitis A Virus (HAV) annually - the leading widely spread causes of acute viral hepatitis in developing countries across all continents. Objective To evaluate the prevalence of anti-HAV antibodies; to determine HAV genotypes by nucleotide sequencing in patients suspected of acute hepatitis at public healthcare institutions; and to assess the association between this infection with age, gender, region, and other risk factors Methods Between October 2019 and May 2023, we analyzed 1,562 patients with more than 18 years old with clinical suspected acute hepatitis. Results Out of the 1,562 individuals, 1,244 were seropositive for Anti-HAV IgG, a median age of 45 years (IQR: 35 to 56) vs. 31 years (IQR: 25 to 39) in non-reactive individuals (p<0.001). A higher seropositivity was found in men compared to women (p=0.002). North region showed the highest seropositivity (p<0.001). There was also an association between poor sanitation conditions and seropositivity, such as lack of sewage collection and consumption of untreated water (p<0.001), as well as an association between heterosexual orientation and higher likelihood of seropositivity (p=0.015). In the logistic regression analysis for anti-HAV IgG seropositivity, age and male sex were significantly associated with seropositivity (OR = 1.09, 95% CI: 1.08 to 1.11, p<0.001; OR = 1.56, 95% CI: 1.16 to 2.11, p=0.004). North region showed a significant increase in the odds for seropositivity compared to all other regions. For anti-HAV IgM, out of the 1,562 individuals, 97 were seropositive, significantly higher in younger individuals [median age of 34 years (IQR: 28 to 40) vs. 42 years (IQR: 32 to 54) in non-reactive individuals (p<0.001)] and in males (p<0.001). South and Southeast regions had higher seropositivity (p<0.001). Non-heterosexual orientation and more than 2 sexual partners significantly correlated with seropositivity (p<0.001). In the logistic regression analysis for anti-HAV IgM, age showed an inverse association with seropositivity (OR = 0.96, 95% CI: 0.94 to 0.98, p<0.001), being more frequent in men (OR = 1.86, 95% CI: 1.11 to 3.21, p=0.021). Consumption of seafood was significantly associated with increased odds of seropositivity for anti-HAV IgM (OR = 2.26, 95% CI: 1.43 to 3.56, p<0.001). South and Southeast regions showed more IgM positive cases than North, Northeast and Midwest regions. Among the 1,562 cases, 35 complete (or almost complete) HAV genomes were successfully recovered from metagenomics sequencing data. These genomes range from 6,625 to 7,462 bp in length (89-100% completeness), sequences were fairly similar in pairwise nucleotide alignment, classified as genotype I.A, and displaying identities ranging from 94.7 to 99.7%. Conclusions Hepatitis A infection was found among 6.2% acute hepatitis cases attended in public services in Brazil while previous infections or vaccinated patients were found in 78.9% patients. While anti-HAV IgG positive patients where most frequent in the North region of Brazil, acute hepatitis A (IgM-positive) were more frequent in South and Southeast regions. Our results reinforce the need to implement vaccination against hepatitis A among individuals with more than 18 years in our country.

The Immunological and Epidemiological Effectiveness of Pediatric Single-Dose Vaccination against Hepatitis A 9 to 11 Years after Its Implementation in the Tyva Republic, the Russian Federation.

Since 2012, universal single-dose HAV vaccination in children aged 3 years and older has been implemented in the Tyva Republic, a region of the Russian Federation. The aim of this prospective non-interventional observational single-center study was to determine the immunological and epidemiological effectiveness of single-dose vaccination against hepatitis A 9 to 11 years after its implementation. The anti-HAV IgG antibodies were determined in two independent cohorts of children who were vaccinated with a single dose of monovalent pediatric inactivated vaccine (HAVRIX® 720 EU) in Tyva in 2012 and recruited 9 years (Year 9 Cohort) and 11 years (Year 11 Cohort) after immunization. The seroprotection rates defined as anti-HAV antibody concentrations ≥10 mIU/mL reached 99.4% (95% CI: 98.2-99.9% [501/504]) in the Year 9 Cohort, but decreased significantly to 75.4% (95% CI: 73.0-77.6% [1006/1335]) in the Year 11 Cohort (p < 0.0001). The anti-HAV geometric mean concentrations decreased from 1446.3 mIU/mL (95% CI: 1347.1-1545.4 mIU/mL) in the Year 9 Cohort to 282.6 mIU/mL (95% CI: 203.8-360.8, p < 0.0001) in the Year 11 Cohort. The HAV vaccination program resulted in zero rates of hepatitis A incidence in the Tyva Republic since 2016. However, the limited monitoring of HAV RNA in sewage and environmental samples demonstrated the ongoing circulation of both the regional epidemic strain of HAV genotype IA and another genotype IA strain imported recently from other parts of the Russian Federation, probably due to subclinical infections in non-vaccinated children under 3 years of age. Taken together, these data indicate the effectiveness of the single-dose HAV vaccination strategy but suggest the need to expand the vaccination program to include children aged 12 months and older to achieve maximum effectiveness.

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 11years, 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.

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.

Two-Center Comparison of Viral Hepatitis A, B, C Seroprevalence among the 18-25 Age Group

Objective: Viral hepatitis is inflammation of the liver due to a viral infection that affects millions of people worldwide, causing thousands of deaths due to acute-chronic infection, liver cancer and cirrhosis. This study is aimed to compare datas of the seroprevalence of markers for viral hepatitis A, B, C among 18-25 age group outpatient clinic patients and healthcare workers between the two University Hospitals from east and west zone of Turkey. Material and Methods: The data of a total of 562 patients and healthcare workers, aged between 18 and 25, who applied to the outpatient clinic at Sütçü İmam University Faculty of Medicine and Onsekiz Mart University Faculty of Medicine Hospital between 01.01.2022 and 01.07.2022, were retrospectively examined. The presence of serological markers against HAV, HBV, HCV and HIV was tested with the ELISA method. Results: Anti-HAV IgG positivity was 25.5% and 40.3% for Çanakkale and Kahramanmaraş, respectively. Anti-HAV seropositivity rate in Kahramanmaraş was statistically significantly higher than in Çanakkale (P&amp;lt;0.001). Anti-HBs positivity was found to be 74.5% and 75.4% for Çanakkale and Kahramanmaraş, which were similar to each other bulundu (P=0.458). HBsAg positivity was detected as 1.5% in Çanakkale and 0.8% in Kahramanmaraş. There was no significant difference between the two cities (P = 0.810). Anti-HCV was found to be positive in one (0.5%) patient in Çanakkale and in four (1.1%) patients in Kahramanmaraş. Anti-HCV positivity was higher in Kahramanmaraş and anti-HIV positivity was higher in Çanakkale (P=.03, P&amp;lt;0.001). It was detected that anti-HBs positivity (80.7%) was higher in HCWs and anti-HAV IgG positivity was higher in non-HCWs (38.4%) (P=.042, P=0.013). There was no significant difference between the 2 groups in terms of anti-HCV and anti-HIV positivity. Conclusion: Due to the low anti-HAV seropositivity rates in the 18-25 age group, this makes this group more risky in terms of HAV infection. Especially due to the anti-HAV positivity in Çanakkale is low compared to Kahramanmaraş, it is recommended to support vaccination in this region. Since health care workers are at risk of having and transmitting hepatitis, it was found to be appropriate getting prevention measures by screening against vaccine-preventable diseases.

Delays in Hepatitis A vaccination in people with HIV in Houston, Texas between 2010 and 2018

BackgroundStudies have demonstrated low hepatitis A virus (HAV) vaccination rates among persons with HIV (PWH). MethodsWe conducted a retrospective study of persons entering HIV care at two clinics in Houston, Texas between 2010 and 2018. We defined those eligible for HAV vaccination as those who had no history of HAV vaccination and had a negative anti-HAV IgG at entry to care. Kaplan-Meier curves summarized time to receipt of HAV vaccines. The proportions of patients who received 1 and 2 HAV vaccines at 6, 12, and 24 months were estimated. Cox proportional hazards regression evaluated associations between patient characteristics and vaccination. Significant factors were included in a multivariable Cox proportional hazards model. ResultsOf 6,515 patients, 1372 were eligible for HAV vaccination. Of eligible patients, 29.2 % received 1 HAV vaccination at 6 months, 37.1 % at 12 months, and 47.8 % at 24 months. At 6 months, 10 % received 2 HAV vaccinations, 21.1 % at 12 months, and 33.4 % at 24 months. In multivariable analysis, men who have sex with men (adjusted HR 1.35, 95 % CI 1.06, 1.73) or those who had CD4 count ≥ 200 cells/µl (adjusted HR 2.52, 95 % CI 1.89, 3.37) had their second vaccination sooner than those who were not men who have sex with men or who had CD4 counts < 200 cells/µl, respectively. Patients > 50 years of age had their second vaccination sooner than those aged 30–50 years (adjusted HR 1.47, 95 % CI 1.08, 1.99). Those with active substance history had a longer time to second vaccination compared to those with no substance use history (adjusted HR 0.57, 95 % CI 0.40, 0.82). ConclusionsHAV vaccination rates were low and highlight the need for effective solutions to address HAV immunization gaps in PWH, especially among young patients, those with active substance use disorders, and those with significant immunocompromise.

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.

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.

Durability of serologic responses to inactivated hepatitis A virus vaccination among people living with HIV following acute hepatitis A outbreak: a 5-year follow-up study

ABSTRACT Serologic responses to hepatitis A virus (HAV) vaccination may wane among immunocompromised populations. To evaluate the long-term seroresponses to 2-dose HAV vaccination, we retrospectively included people living with HIV (PLWH) who had achieved seroconversion within 12 months after vaccination at a university hospital during an outbreak of acute hepatitis A between 2015 and 2017. PLWH included in the study received either Havrix or Vaqta. The seroresponses were evaluated 60 months after the second dose of vaccination and estimated by the intention-to-treat (ITT) with last-observation-carried-forward (LOCF) and per-protocol (PP) analyses. Overall, 986 PLWH (median age, 34 years and CD4 count, 587 cells/µL) were included. The rates of PLWH with persistent seroprotection at month 60 of vaccination were 90.7% (894/986) and 97.4% (748/768) in the ITT with LOCF and PP analyses, respectively. PLWH with persistent seroprotection had achieved higher peak anti-HAV IgG titers after vaccination and had a slower decline in antibody levels compared with those with seroreversion. In the multivariable analysis, seroreversion at month 60 was associated with a higher body-mass index (per 1-kg/m2 increase, AOR, 1.10; 95% CI, 1.04-1.17), lowest-ever CD4 count (per 10-cell/µL increase, AOR 0.98; 95% CI, 0.97-1.00), plasma HIV RNA <200 copies/ml at vaccination (AOR, 0.28; 95% CI, 0.14-0.59), and having received Vaqta as the first dose of HAV vaccination (AOR, 0.44; 95% CI, 0.27-0.70). The seroprotection against HAV remained high in the long-term follow-up among PLWH on antiretroviral therapy after 2-dose HAV vaccination. Regular monitoring of seroresponses and timely administration of HAV vaccines are warranted to maintain seroprotection.

EVALUATION OF THE RATE OF HEPATITIS A IMMUNITY IN A SMALL CITY AFTER THE VACCINATION PROGRAM: ONE CENTER EXPERIENCE

Purpose: Hepatitis A is an infectious disease caused by hepatitis A virus (HAV). Symptomatic infection causes health care costs with loss of labor and school time. HAV outbreaks may cause economic problems by disrupting trade and tourism. The aim of this study is to determine the rate of immunity against HAV infection in a sample of pediatric population.&#x0D; Methods: The study group consisted of all children who underwent anti-HAV IgG evaluation for any reason between January 1, 2012 and December 31, 2020. The data about age, date of birth, sex, residence, vaccination status were retrospectively collected from the hospital record system. Anti-HAV IgG status was determined by chemiluminescent microparticle immunassay kits. The statistical analyses were presented with descriptive methods. &#x0D; Results: Overall 1189 children aged 1-17 years old enrolled to the study. The rate of anti HAV IgG seropositivity was 41.2% in the whole study group. The rates of completed vaccination scheme and seropositivity were 10.7% and 92.2%. Natural immunity rate was 32.6%.&#x0D; Conclusion: The 7-17 age group was found to be susceptible to the acute infection, they were considered as the new target population of vaccination. Vaccination seemed to be the most effective way of providing seropositivity to get rid of acute infection risk and eliminating geographic and socioeconomic differences.

Assessment of herd immunity to hepatitis A virus among the population of the Republic of Tatarstan

Introduction. Identification of the groups of the population most susceptible to infection with hepatitis A virus (HAV) is a key component for the regulation of anti-epidemic measures during the activation of the epidemic process.&#x0D; The aim аssessment of the herd immunity to hepatitis A (HA) among different age groups of the population of the Republic of Tatarstan.&#x0D; Materials and methods. The analysis of the HA incidence of from 2006 to 2021 and the study of herd immunity to HA among 6,553 persons from different age groups that were not vaccinated against HA were carried out. Participants with protective concentrations of antibodies to HAV of 20 mMU/ml or more were considered as seropositive.&#x0D; Results. The analysis showed a low intensity of the epidemic process in general (3.6 0.3о/оооо), while the HA incidence among children and adults was significantly different, with incidence rates 2.3 times higher in the first group (6.9 0.9 and 3.0 0.3о/оооо, respectively). The epidemic process is determined by persons aged 1517 years (8.2 2.5о/оооо), 36 years (7.0 1.9о/оооо, 714 years (6.2 1.3о/оооо), the incidence among these age groups in all observed years remained the highest. In general, the proportion of seropositive children was 32.1 1.0%. Among adults, anti-HAV IgG antibodies in a protective concentration was detected in 68.2 0.7%. The highest frequency of anti-HAV IgG positive samples was observed among persons aged 5059 years 89.4 1.1%, in age group 4049 years 73.5 1.2%, in age group 3039 years 65.5 1.3%, and in age group 2029 years 48.2 1.6%. In total, 56.9 0.6% of the examined individuals had protective antibodies to HAV. The detection rates of anti-HAV IgG antibodies were significantly different in all age groups (p 0.05).

Assessment of the possible impact of hepatitis viruses on the development and course of autoimmune liver diseases

Despite the well-studied pathogenesis, the etiology of autoimmune liver disease (AILD) remains unknown. To determine the significance of hepatitis A, B, C and E viruses in the development and progression of AILD. A single-center case-control study included 139 patients with AILD: autoimmune hepatitis - AIH (n=46), primary biliary cholangitis - PBS (n=74), primary sclerosing cholangitis - PSC (n=19). Median age 56 years, IQR 48-65 years. 125 patients - without liver disease - control group (median age 55 years, IQR 46-65 years). Testing of blood serum samples for anti-HAV IgG, anti-HEV IgG, HBsAg, anti-HBc IgG, anti-HCV was carried out by solid-phase ELISA. All patients underwent fibroelastography. Needle liver biopsy - 70 patients: AIH (n=37), PBC (n=28) and PSC (n=5). Ab(IgG) to HAV and HBV were detected in patients with AILD significantly more often than in the control group (74.8% vs 54.4%; p<0.001). An increased risk of developing AILD was established in patients with the presence of antibodies to HAV, HBV and HEV (OR 2.491, CI 95% [1.481-4.190]). The highest risk of developing PBC was found in patients with antibodies to HAV and HBV (OR 3.008, 95% CI [1.633-5.542] and OR 2.515, 95% CI [1.242-5.093]). In patients with severe liver fibrosis (F3-F4 according to METAVIR), antibodies to HAV and HBV were detected significantly more often than in patients with F0-F2 [85% vs 65%; p=0.008]. In our work, we have demonstrated the relationship of past hepatitis A, B, E and AILD, as well as the high risk of developing severe fibrosis in patients with AILD and markers of hepatitis A and B viruses indicates the possible involvement of these viruses in the pathogenesis of AILD.

Viral hepatitis A in the Voronezh region: a controlled or «self-controlled» infection?

Over the past decade, in most regions of Russia, including the Voronezh region, the epidemic process of viral hepatitis A (HAV) has been of low intensity. The aim of the study was to study the incidence of viral hepatitis A in the Voronezh region for the period 1993–2021, taking into account the results of laboratory studies conducted as part of epidemiological surveillance and preventive measures. The research materials were statistical forms approved by Rosstat, analytical reports of Rospotrebnadzor for the Voronezh region, departmental reports of regional medicaorganizations to the Regional Health Department. The data of examination for anti-HAV IgG of contact persons in the outbreaks were analyzed. The materials were processed using the methods of epidemiological analysis. A downward trend in the incidence of HAV with the properties of a «controlled» infection was established: the severity of seasonal rises, a shift in the proportion of cases to the adult population, school-age children. At the same time, coverage of HAV vaccination among the population of the region is low and cannot yet have a significant impact on reducing the incidence. Immunization is important in outbreaks to prevent group spread and during natural disasters. Against the background of improved provision of the population with quality water, the importance of water as a factor in the transmission of infection has decreased. During the study period, only one focus with a presumably waterway was noted. Complexes of preventive and anti-epidemic measures are being effectively implemented in the region. The selective vaccination used at this stage of the epidemic process is sufficient for the Voronezh region.

Persistence of immunity against hepatitis A in Brazilian children vaccinated with a single dose of inactivated virus vaccine.

In 2014, the Brazilian National Immunization Program implemented the universal vaccination against the hepatitis A virus (HAV) for children aged 12 months and older, applying a single dose of the inactivated virus vaccine. It is essential to carry out follow-up studies in this population, aiming to verify the longevity of HAV immunological memory. This study evaluated the humoral and cellular immune response of a cohort of children vaccinated between 2014 and 2015, and further investigated between 2015 and 2016, and who had their initial antibody response assessed after the single dose. A second evaluation took place in January 2022. We examined 109 children out of the 252 that took part in the initial cohort. Seventy (64.2%) of them had anti-HAV IgG antibodies. Cellular immune response assays were performed in 37 anti-HAV-negative and 30 anti-HAV-positive children. Production of interferon-gamma (IFN-y) stimulated with the VP1 antigen was demonstrated in 34.3% of these 67 samples. Of the 37 negative anti-HAV samples, 12 (32.4%) produced IFN-y. Among the 30 anti-HAV-positive, 11 (36.7%) produced IFN-y. In total, 82 (76.6%) children presented some type of immune response against HAV. These findings demonstrate the persistence of immunological memory against HAV in the majority of children vaccinated between 6 and 7 years with a single dose of the inactivated virus vaccine.

Prevalence of HIV and Viral Hepatitis Markers among Healthcare Workers in the Republic of Guinea.

Healthcare workers are much more likely to be infected with HIV and hepatitis viruses compared to the general population. Although healthcare workers are more aware of HIV and hepatitis viruses, several countries in Africa lack a comprehensive grasp of disease routes and transmission risks. The aim of this study was to assess the prevalence of the serological and molecular biological markers of HIV and viral hepatitis among healthcare workers in the Republic of Guinea. The study material was 74 blood serum samples collected from healthcare workers who received additional training at the Institute of Applied Biological Research of Guinea (IRBAG, Kindia, Republic of Guinea). The markers examined included HBsAg, HBeAg, anti-HBs IgG, anti-HBcore IgG, anti-HCV qualitative determination, anti-HEV IgM and IgG, anti-HAV IgM and IgG, and anti-HIV. For viral DNA and RNA detection, nucleic acids were extracted from blood serum, and viral presence was inferred using real-time PCR with hybridization fluorescence detection. A high prevalence of viral hepatitis B markers was shown, and significantly fewer cases of viral hepatitis C and HIV were detected. Almost all examined medical workers had anti-HAV IgG antibodies, but no antibodies to hepatitis E virus. Apparently, the identified markers depend on the general prevalence of certain pathogens in the region and are associated with the traditions and characteristics of the country's residents.

The prevalence of latent/chronic infection in liver transplant candidates in Taleghani Hospital of Tehran, Iran, from 2020 until 2021.

The present study aimed to study the prevalence of various latent infections in pre-transplanted patients. Due to chronic immunosuppressive therapy, patients receiving organ transplants are at risk for reactivation of various infections. Due to the complications in the course of diagnosing and treating the post-transplant infection, screening transplant recipients and donors is vital. This retrospective cohort study was performed between March 2020 and 2021. A total of 193 patients receiving a liver transplant in Taleghani Hospital, Tehran, Iran were enrolled. One-hundred and three (53.4%) patients were men, with an average age of 48.4 ± 13.3 years. Among viruses, 177 (91.7%) patients had a positive IgG titer for CMV. Anti-EBV IgG was positive in 169 (87.6%) patients. One-hundred and seventy-five (90.7%) patients had a positive IgG titer for the VZV. One-hundred and sixty-six (86.0%) cases had positive IgG anti-HSV antibodies. According to our findings, none of the patients were infected with HIV, but 9 (4.7%) cases and 141 (73.1%) had positive anti-HCV and anti-HAV IgG antibodies, respectively. HBV surface (HBs) antigen was also reported positive in 17 (8.8%) patients, while the HBs antibody was positive in 29 (15.0%) patients. In our study, most of the patients had positive serology for latent viral infections such as CMV, EBV, VZV, and HSV, but the prevalence of latent tuberculosis and viral hepatitis was low among transplant candidates.

Hepatit A Epidemiyolojisi ve Duyarlı Nüfusta Değişim

Aim: The incidence of hepatitis A (HepA) has decreased due to vaccination and improved hygiene conditions. However, the age of onset of the disease has shifted from childhood to adulthood. Children with HepA are mildly symptomatic, whereas the course of the disease in adults may be severe. The aim of this study was to examine the change in HepA seroprevalence and identify the population susceptible to HepA. Material and Methods: A total of 10132 patients who were tested anti-Hepatitis A virus immunoglobulin G (anti-HAV IgG) between 2016 and 2019 were reviewed retrospectively, and included in this study. The patients were divided into five groups according to their age, and seropositivity rates were compared between age groups. The relevant data of the healthcare professionals were also evaluated separately. Results: The overall seropositivity rate was 60.1% (n=6088). The seropositivity rate was found 29.0% (n=944) in the 18 to 24 years range, 49.7% (n=837) in the 25 to 29 years range, 60.6% (n=689) in the 30 to 34 years range, 76.6% (n=784) in the 35 to 39 years range, and 93.3% (n=2834) in the ≥40 years groups. The seropositivity rate was found 36.1% (n=1781) and 82.9% (n=4307) in patients &amp;lt;30 and ≥30 years groups, respectively (p&amp;lt;0.001). Conclusion: In recent decades, there has been a significant change in HepA seroprevalence. This change has resulted in the emergence of a young adult population susceptible to possible HepA outbreaks. Thus, seronegative young adults may be considered at risk for HepA and routine vaccination may be considered.

Age Group-Specific Assessment of Changing Seroepidemiology of Hepatitis A Virus Infection in North India.

Introduction Routine immunization against hepatitis A virus (HAV) infection has not been warranted in India, but an epidemiological shift from hyperendemicity to intermediate endemicity has been detected in recent years. The present studywas planned to gather theage group-specificseroprevalence data of hepatitis A IgG antibodies in various age groupsandevaluateany early trends of seroepidemiological shift. Method This was a hospital-based cross-sectional study. The detection of IgG antibodies for hepatitis A was done using an HAV Ab kit (Dia.Pro, Milan, Italy) in sera of individuals from >1 to 80 years of age and consenting to participate. Data on sociodemographic factors and potentially predisposing factors of HAV was collected on a predesigned questionnaire. At the time of final analysis, patients were divided into three groups children one to <18 years, adults ≥18 to <60 years, and old ≥60 to 80 years for comparative analysis. Result A total of 1,250 patients were included in the final analysis (129 children, 928 adults, and 193 old). The male/female ratio of the study participants was 1.4:1. The majority (85%) of them came from rural and semi-urban areas. They generally had lower socioeconomic status (SES) with poor literacy rates. Most of the enrolled cases(n=800/1,250, 64%) reported the use of groundwater, and 58.7% (n=734/1,250) consume water without any purification. Of the study participants,90.8% reported the use of toilets for defecation, and 96.7% of the cases use soap for handwashing after defecation. The majority of adult (90%) and old age (99%) participants were seropositive for anti-HAV IgG antibodies as compared to children (80%). No significant differences were observed in the seropositivity rates and the SES class of the study participants. Conclusion About 20% of children did not have anti-HAV IgG antibodies in the present study, indicating that they are not exposed to HAV. This could bebecause of their better living conditions such as the availability of safe drinking water and improved sanitation and hygiene. We support the current guidelines of the Indian Academy of Pediatrics (IAP), which recommends immunization for hepatitis A vaccination at 12 months of age. Adult vaccination is notneeded in North India.

Hepatit B Yüzey Antijeni (HBsAg) Pozitif Hastalarda Hepatit A ve Hepatit E Virüsü Seropozitifliği

Introduction: In this study, we aimed to determine the anti-HAV IgG and anti-HEV IgG seroprevalence in patients admitted to our clinic with Hepatitis B surface antigen (HBsAg) positivity. &#x0D; Material and Method: Data of 1827 patients followed up on for HBsAg positivity between 2010 and 2019 were obtained retrospectively. &#x0D; Results: The mean age of 1827 HBsAg positive patients was 42.71±14.84; there were 730 (39.96%) female patients and 1097 (60.04%)male. Of the 923 HBsAg positive patients whose anti-HAV IgG was measured, 830(%89,9) were detected to be positive, and 93 (10.1%) negative. Anti-HAV IgG negative patients were most often in the 21-30 age range (38.7%). Age medians were significantly different between the groups (p=0.001). HBsAg positive patients who were also positive for anti-HAV IgG tended to be older than anti-HAV IgG negative patients. In contrast, there was no significant difference in gender between anti-HAV IgG negative and positive patients (p=0.674). Of 143 HBsAg positive patients who were tested for anti-HEV-IgG, five were positive (3.5%).&#x0D; Conclusion: It is of interest that we found a lower rate of anti-HAV IgG positivity in young Chronic Hepatitis B patients. When hepatitis B virus is detected, a test for anti-HAV IgG should be requested from patients and if the test result is negative, the patient should be vaccinated. Our study data analysis also revealed a low anti-HEV IgG positivity.