scholarly journals A Study of Hepatitis A Seroprevalence in a Paediatric and Adolescent Population of the Province of Florence (Italy) in the Period 2017–2018 Confirms Tuscany a Low Endemic Area

Vaccines ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1194
Author(s):  
Beatrice Zanella ◽  
Sara Boccalini ◽  
Massimiliano Alberto Biamonte ◽  
Duccio Giorgetti ◽  
Marco Menicacci ◽  
...  
Keyword(s):  
Children And Adolescents ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Qualitative Evaluation ◽  
Risk Groups ◽  
Enzyme Linked Immunosorbent Assay ◽  
Surveillance Systems ◽  
Subclinical Infection ◽  
Significant Difference ◽  
Status Data

Background: Italy is considered an area with very low HAV (hepatitis A virus) endemicity. Currently in Italy the anti-HAV vaccine is recommended only for specific risk groups and there is no universal vaccination program. The aim of this study was to assess the level of immunity against hepatitis A in a sample of children and adolescents from the province of Florence. Methods: A total of 165 sera were collected from subjects aged 1 to 18 years, proportionally selected according to the general population size and stratified by age and sex. A qualitative evaluation of anti-HAV antibodies was performed using the enzyme-linked immunosorbent assay (ELISA). Anamnestic and vaccination status data were also collected. Results: Our study showed a hepatitis A seroprevalence of 9.1% in the enrolled population. A statistically significant difference in the prevalence of anti-HAV was found between Italian and non-Italian subjects. About half of the population having anti-HAV antibodies was reported to be vaccinated, and no cases of hepatitis A were found. Conclusions: The data from our study confirmed Tuscany as an area with low HAV endemicity and showed that hepatitis A seroprevalence is significantly higher in foreign children and adolescents. The presence of more seropositive subjects than those vaccinated was probably due to a natural immunization achieved through a subclinical infection and/or to underreporting of the surveillance systems.

Detection of Hepatitis a Virus in Drinking Water by Enzyme -Immunoassay Using Ultracentrifugation for Virus Concentration

1985 ◽  
Vol 17 (10) ◽  
pp. 39-41 ◽  
Author(s):  
A. Schnattinger
Keyword(s):  
Membrane Filtration ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Solid Phase ◽  
Phosphate Buffer Solution ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Concentration ◽  
Buffer Solution ◽  
Solution Ph ◽  
Two Stage

Ten litres of tapwater were seeded with 200 µl (8×108 HAV particles) of a commercial (Organon Teknika) suspension of hepatitis A virus. Following WALTER and RÜDIGER (1981), the contaminated tapwater was treated with a two-stage technique for concentration of viruses from solutions with low virus titers. The two-stage technique consists of aluminium hydroxideflocculation (200 mg/l Al2(SO4)3. 18 H2O, pH 5,4-5,6) as first stage, the second stage of a lysis of aluminium hydroxidegel with citric acid/sodium citrate-buffer (pH 4,7; 1 ml/l sample), separation of viruses from the lysate by ultracentrifugation and suspension in 1 ml phosphate buffer solution (pH 7,2). A commercial solid phase enzyme-linked immunosorbent assay (ELISA) was used for the detection of HAV. HAV was detecterl in the 10.000:1 concentrates, but not in the seeded 101 samples. Approximately 4×108 of the inoculated 8×108 HAV particles were found in the 1 ml concentrates. The efficiency of detection is about 50%, the virus concentration 5000-fold. Although the percentage loss of HAV in comparison with concentration by means of membrane filtration is similar, the ultracentrifugation method yields a larger sample/concentrate ratio, so that smaller amounts of HAV can be detected more efficiently because of the smaller end-volume.

scholarly journals Hepatitis A virus infections, immunisations and demographic determinants in children and adolescents, Germany

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Kai Michaelis ◽  
Christina Poethko-Müller ◽  
Ronny Kuhnert ◽  
Klaus Stark ◽  
Mirko Faber
Keyword(s):  
Children And Adolescents ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Virus Infections

scholarly journals Susceptibility to Hepatitis A Virus Infection in the United States, 2007–2016

2020 ◽  
Vol 71 (10) ◽  
pp. e571-e579 ◽  
Author(s):  
Shaoman Yin ◽  
Laurie Barker ◽  
Kathleen N Ly ◽  
Greta Kilmer ◽  
Monique A Foster ◽  
...  
Keyword(s):  
United States ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Risk Groups ◽  
The United States ◽  
Poverty Level ◽  
Health And Nutrition ◽  
National Immunization ◽  
Vaccination Recommendations ◽  
Sex With Men

Abstract Background Despite national immunization efforts, including universal childhood hepatitis A (HepA) vaccination recommendations in 2006, hepatitis A virus (HAV)–associated outbreaks have increased in the United States. Unvaccinated or previously uninfected persons are susceptible to HAV infection, yet the susceptibility in the US population is not well known. Methods Using National Health and Nutrition Examination Survey 2007–2016 data, we estimated HAV susceptibility prevalence (total HAV antibody negative) among persons aged ≥2 years. Among US-born adults aged ≥20 years, we examined prevalence, predictors, and age-adjusted trends of HAV susceptibility by sociodemographic characteristics. We assessed HAV susceptibility and self-reported nonvaccination to HepA among risk groups and the “immunization cohort” (those born in or after 2004). Results Among US-born adults aged ≥20 years, HAV susceptibility prevalence was 74.1% (95% confidence interval, 72.9–75.3%) during 2007–2016. Predictors of HAV susceptibility were age group 30–49 years, non-Hispanic white/black, 130% above the poverty level, and no health insurance. Prevalences of HAV susceptibility and nonvaccination to HepA, respectively, were 72.9% and 73.1% among persons who reported injection drug use, 67.5% and 65.2% among men who had sex with men, 55.2% and 75.1% among persons with hepatitis B or hepatitis C, and 22.6% and 25.9% among the immunization cohort. Susceptibility and nonvaccination decreased over time among the immunization cohort but remained stable among risk groups. Conclusions During 2007–2016, approximately three-fourths of US-born adults remained HAV susceptible. Enhanced vaccination efforts are critically needed, particularly targeting adults at highest risk for HAV infection, to mitigate the current outbreaks.

scholarly journals Exposure to enteroviruses and hepatitis A virus among divers in environmental waters in France, first biological and serological survey of a controlled cohort

1994 ◽  
Vol 113 (3) ◽  
pp. 541-549 ◽  
Author(s):  
D. Garin ◽  
F. Fuchs ◽  
J. M. Crance ◽  
Y. Rouby ◽  
J. C. Chapalain ◽  
...  
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Training School ◽  
Environmental Waters ◽  
Viral Isolation ◽  
Viral Contamination ◽  
Coxsackievirus B4 ◽  
Concentration Technique ◽  
Significant Difference ◽  
Stool Specimens

SUMMARYAn epidemiological study of hepatitis A and enteroviruses was conducted in a military diving training school, by evaluating the viral contamination of water using an ultrafiltration concentration technique, and assessing seroconversion and the presence of virus in stool specimens obtained from 109 divers and 48 controls. Three of 29 water specimens were positive for enterovirus by cell culture and 9 by molecular hybridization. There was little or no risk of virus infection during the training course (49 h exposure) because there was no significant difference between divers and controls for both viral isolation and seroconversion. However, a higher percentage of coxsackievirus B4 and B5 seropositive divers suggests that these were more exposed during previous water training. No hepatitis A virus (HAV) detection and no seroconversion to HAV was observed. The rate of HAV seropositive subjects was 17% in this 24·5-year-old population

scholarly journals A Novel Marsupial Hepatitis A Virus Corroborates Complex Evolutionary Patterns Shaping the Genus Hepatovirus

2018 ◽  
Vol 92 (13) ◽  
Author(s):  
Ianei de Oliveira Carneiro ◽  
Anna-Lena Sander ◽  
Namá Silva ◽  
Andres Moreira-Soto ◽  
Andrea Normann ◽  
...  
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Genome Structure ◽  
Northeastern Brazil ◽  
Enzyme Linked Immunosorbent Assay ◽  
Evolutionary Patterns ◽  
Host Switch ◽  
Content Type ◽  
Evolutionary Origins ◽  
Phylogenetic Reconstructions

ABSTRACT The discovery of highly diverse nonprimate hepatoviruses illuminated the evolutionary origins of hepatitis A virus (HAV) ancestors in mammals other than primates. Marsupials are ancient mammals that diverged from other Eutheria during the Jurassic. Viruses from marsupials may thus provide important insight into virus evolution. To investigate Hepatovirus macroevolutionary patterns, we sampled 112 opossums in northeastern Brazil. A novel marsupial HAV (MHAV) in the Brazilian common opossum ( Didelphis aurita ) was detected by nested reverse transcription-PCR (RT-PCR). MHAV concentration in the liver was high, at 2.5 × 10 9 RNA copies/g, and at least 300-fold higher than those in other solid organs, suggesting hepatotropism. Hepatovirus seroprevalence in D. aurita was 26.6% as determined using an enzyme-linked immunosorbent assay (ELISA). Endpoint titers in confirmatory immunofluorescence assays were high, and marsupial antibodies colocalized with anti-HAV control sera, suggesting specificity of serological detection and considerable antigenic relatedness between HAV and MHAV. MHAV showed all genomic hallmarks defining hepatoviruses, including late-domain motifs likely involved in quasi-envelope acquisition, a predicted C-terminal pX extension of VP1, strong avoidance of CpG dinucleotides, and a type 3 internal ribosomal entry site. Translated polyprotein gene sequence distances of at least 23.7% from other hepatoviruses suggested that MHAV represents a novel Hepatovirus species. Conserved predicted cleavage sites suggested similarities in polyprotein processing between HAV and MHAV. MHAV was nested within rodent hepatoviruses in phylogenetic reconstructions, suggesting an ancestral hepatovirus host switch from rodents into marsupials. Cophylogenetic reconciliations of host and hepatovirus phylogenies confirmed that host-independent macroevolutionary patterns shaped the phylogenetic relationships of extant hepatoviruses. Although marsupials are synanthropic and consumed as wild game in Brazil, HAV community protective immunity may limit the zoonotic potential of MHAV. IMPORTANCE Hepatitis A virus (HAV) is a ubiquitous cause of acute hepatitis in humans. Recent findings revealed the evolutionary origins of HAV and the genus Hepatovirus defined by HAV in mammals other than primates in general and in small mammals in particular. The factors shaping the genealogy of extant hepatoviruses are unclear. We sampled marsupials, one of the most ancient mammalian lineages, and identified a novel marsupial HAV (MHAV). The novel MHAV shared specific features with HAV, including hepatotropism, antigenicity, genome structure, and a common ancestor in phylogenetic reconstructions. Coevolutionary analyses revealed that host-independent evolutionary patterns contributed most to the current phylogeny of hepatoviruses and that MHAV was the most drastic example of a cross-order host switch of any hepatovirus observed so far. The divergence of marsupials from other mammals offers unique opportunities to investigate HAV species barriers and whether mechanisms of HAV immune control are evolutionarily conserved.

Changing risk profile of hepatitis A in The Netherlands: a comparison of seroprevalence in 1995–1996 and 2006–2007

2011 ◽  
Vol 139 (8) ◽  
pp. 1172-1180 ◽  
Author(s):  
L. VERHOEF ◽  
H. J. BOOT ◽  
M. KOOPMANS ◽  
L. MOLLEMA ◽  
F. VAN DER KLIS ◽  
...  
Keyword(s):  
The Netherlands ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Risk Groups ◽  
Second World War ◽  
World War ◽  
Susceptible Population ◽  
Prophylactic Vaccination ◽  
The Cost ◽  
Second World

SUMMARYThe prevalence of antibodies to hepatitis A virus (HAV) was assessed in a nationwide sample (n=6229) in The Netherlands in 2006–2007, and compared to the seroprevalence in a similar study in 1995–1996 (n=7376). The overall seroprevalence increased from 34% in 1995–1996 to 39% in 2006–2007, mainly due to vaccination of travellers and an increased immigrant population. Risk factors remain travelling to, and originating from, endemic regions, and vaccination is targeted currently at these risk groups. Our results show a trend of increasing age of the susceptible population. These people would also benefit from HAV vaccination because they are likely to develop clinically serious symptoms after infection, and are increasingly at risk of exposure through imported viruses through foods or travellers. The cost-effectiveness of adding elderly people born after the Second World War as a target group for prophylactic vaccination to reduce morbidity and mortality after HAV infection should be assessed.

scholarly journals Determinants of Hepatitis A Vaccine Immunity in a Cohort of Human Immunodeficiency Virus-Infected Children Living in Switzerland

2012 ◽  
Vol 19 (11) ◽  
pp. 1751-1757 ◽  
Author(s):  
Pierre Alex Crisinel ◽  
Klara Maria Posfay-Barbe ◽  
Christoph Aebi ◽  
Jean-Jacques Cheseaux ◽  
Christian Kahlert ◽  
...  
Keyword(s):  
T Cell ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Geometric Mean ◽  
Vaccine Dose ◽  
High Rate ◽  
Enzyme Linked Immunosorbent Assay ◽  
Healthy Children ◽  
Vaccine Responses ◽  
Cell Counts

ABSTRACTVaccination in HIV-infected children is often less effective than in healthy children. The goal of this study was to assess vaccine responses to hepatitis A virus (HAV) in HIV-infected children. Children of the Swiss Mother and Child HIV Cohort Study (MoCHiV) were enrolled prospectively. Recommendations for initial, catch-up, and additional HAV immunizations were based upon baseline antibody concentrations and vaccine history. HAV IgG was assessed by enzyme-linked immunosorbent assay (ELISA) with a protective cutoff value defined as ≥10 mIU/ml. Eighty-seven patients were included (median age, 11 years; range, 3.4 to 21.2 years). Forty-two patients were seropositive (48.3%) for HAV. Among 45 (51.7%) seronegative patients, 36 had not received any HAV vaccine dose and were considered naïve. Vaccine responses were assessed after the first dose in 29/35 naïve patients and after the second dose in 33/39 children (25 initially naïve patients, 4 seronegative patients, and 4 seropositive patients that had already received 1 dose of vaccine). Seroconversion was 86% after 1 dose and 97% after 2 doses, with a geometric mean concentration of 962 mIU/ml after the second dose. A baseline CD4+T cell count below 750 cells/μl significantly reduced the post-2nd-dose response (P= 0.005). Despite a high rate of seroconversion, patients with CD4+T cell counts of <750/μl had lower anti-HAV antibody concentrations. This may translate into a shorter protection time. Hence, monitoring humoral immunity may be necessary to provide supplementary doses as needed.

scholarly journals Comparative hepatitis A seroepidemiology in 10 European countries

2012 ◽  
Vol 140 (12) ◽  
pp. 2172-2181 ◽  
Author(s):  
S. KURKELA ◽  
R. PEBODY ◽  
G. KAFATOS ◽  
N. ANDREWS ◽  
C. BARBARA ◽  
...  
Keyword(s):  
Disease Burden ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Age Groups ◽  
Risk Groups ◽  
Vaccination Policy ◽  
Laboratory Results ◽  
Children And Young Adults ◽  
Middle Aged Adults ◽  
Local Laboratory

SUMMARYThe WHO recommends hepatitis A virus (HAV) immunization according to level of transmission and disease burden. We aimed to identify susceptible age groups by standardized serosurveys to inform HAV vaccination policy in participating countries: Belgium, Czech Republic, England, Finland, Germany, Italy, Lithuania, Malta, Romania, and Slovakia. Each country tested national serum banks (n = 1854–6748), collected during 1996–2004, for anti-HAV antibodies. Local laboratory results were standardized to common units. Forty-one per cent of those aged <30 years and 6% of those aged ⩾30 years were susceptible to HAV in Romania; compared to 70–94% and 26–71%, respectively, elsewhere. Romania reported high HAV incidence in children and young adults. Other countries reported HAV disease primarily in older risk groups. The results suggest low level of HAV transmission in most of Europe. Romania, however, appeared as an area with intermediate transmission. Vaccination of risk groups in countries with high susceptibility of young and middle-aged adults needs to be continued.

Evaluation of a Sensitive Reverse Transcription PCR–Enzyme-Linked Immunosorbent Assay for Detection of Hepatitis A Virus in Oysters (Saccostrea glomerata) on the East Coast of the Gulf of Thailand

2014 ◽  
Vol 77 (5) ◽  
pp. 859-863 ◽  
Author(s):  
URAIWAN INTAMASO ◽  
SITTHISAK KETKHUNTHOD
Keyword(s):  
Immunosorbent Assay ◽  
Reverse Transcription ◽  
Hepatitis A ◽  
East Coast ◽  
Hepatitis A Virus ◽  
Detection Sensitivity ◽  
Enzyme Linked Immunosorbent Assay ◽  
Gulf Of Thailand ◽  
Rt Pcr ◽  
The Gulf Of Thailand

Hepatitis A virus (HAV) contamination in food can lead to major health problems. We developed a combination reverse transcription (RT) PCR method plus enzyme-linked immunosorbent assay (ELISA) to detect HAV in fresh oysters harvested along the east coast of the Gulf of Thailand. Viral nucleic acid was extracted via the glycine–arginine–polyethylene glycol method followed by RT-PCR amplification with specifically designed primers against HAV and an ELISA to detect the digoxigenin-labeled RT-PCR products. The ELISA in concert with the RT-PCR protocol further increased the detection sensitivity by 100-fold for the HAV genome and 10-fold in artificially contaminated oysters. The overall sensitivity of the RT-PCR in combination with the ELISA was 31.88 pg and 16 PFU/g, respectively. The ELISA increases the specificity of the RT-PCR assay for detecting naturally occurring HAV in oysters. This combined RT-PCR-ELISA approach is a practical and sensitive method for HAV detection and can be utilized in routine screening for HAV in shellfish.

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