Evidence map›Paper›PMID 42163135›Full record

ArticleBMC infectious diseases2026

Genetic variability of hepatitis A virus genotype I strains in Bulgaria, 2011-2023.

Elitsa Golkocheva-Markova, Alessandra Lo Presti, Michele Equestre, Stefania Taffon, Angela Costantino, Elisabetta Madonna, Cinzia Marcantonio, Ludovica Arcopinto, Giulia Costanzi, Stanislav Kotsev and 3 more

Abstract read
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Article in BMC infectious diseases, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

13 authors.

Elitsa Golkocheva-Markova *NRL Hepatitis Viruses, Department of Virology, National Centre of Infectious and Parasitic Diseases, Sofia, Bulgaria.
Alessandra Lo Presti *National Reference Laboratory for HAV, Viral Hepatitis Unit, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy. alessandra.lopresti@iss.it.
Michele EquestreDepartment of Neuroscience, Istituto Superiore di Sanità, Rome, Italy.
Stefania TaffonNational Reference Laboratory for HAV, Viral Hepatitis Unit, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
Angela CostantinoNational Reference Laboratory for HAV, Viral Hepatitis Unit, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
Elisabetta MadonnaNational Reference Laboratory for HAV, Viral Hepatitis Unit, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
Cinzia MarcantonioNational Reference Laboratory for HAV, Viral Hepatitis Unit, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
Ludovica ArcopintoNational Reference Laboratory for HAV, Viral Hepatitis Unit, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
Giulia CostanziNational Reference Laboratory for HAV, Viral Hepatitis Unit, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
Stanislav KotsevDepartment of Infectious Diseases, Pazardzhik Multiprofile Hospital for Active Treatment, Pazardzhik, Bulgaria.
Valeri VelevDepartment of Epidemiology and Hygiene, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria.
Anna Rita CiccaglioneNational Reference Laboratory for HAV, Viral Hepatitis Unit, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
Roberto BruniNational Reference Laboratory for HAV, Viral Hepatitis Unit, Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundThe HAV transmission generally occurs through faecal-oral transmission, contaminated water or food, poor sanitary conditions or poor hygiene. Bulgaria is considered a country in transition between an intermediate and a low endemicity profile with significant number of cases and cyclic outbreaks. A phylogenetic, comparative analysis was applied to genotype I Bulgarian sequences collected from 2011 to 2023 to investigate the HAV circulation, the molecular epidemiology, the phylogenetic relationships respect to foreign sequences and gene flows between different Bulgarian towns.

methodsFive different HAV IA and IB VP1-2A dataset were investigated through phylogenetic analysis. The sequence alignments were conducted through MAFFT, under the Galaxy platform, followed by manual editing with Bioedit. Bayesian phylogeny was obtained with BEAST, the gene flow migration analysis in Bulgaria was explored through Mac Clade.

resultsGenotyping of the HAV sequences from Bulgaria revealed two main supported clades corresponding to the IA (n = 115) and IB (n = 120) subtypes. Phylogenetic analysis in IA highlighted a major cluster with strains strictly related to the frozen berries European outbreak. Other minor clusters indicated the simultaneous circulation of different variants. In HAV IB a major cluster of very similar sequences was reported, confirming the low variability. The Bayesian tree indicated intermixing between Bulgarian and foreign strains both in IA and IB. Time scaled phylogeny revealed that HAV IA began circulating in Bulgaria before the genotype IB, confirming previous data. For HAV genotype IA the gene flow analysis indicated bidirectional exchanges involving Sofia and Samokov (each 3.3% of exchange) and Samokov with Dolna Banja (each 3.3% of exchange). Other supported flows (3.3% of exchange) were identified. For IB gene flow analysis showed a 30% from Sofia to Samokov, a 10% from Sofia to Pernik, from Sofia to Novachene and from Novachene to Botevgrad.

conclusionsThe Bayesian approach allowed to estimate the origin, circulation of the HAV epidemic in Bulgaria, to follow the trend of the infections during time. Gene flows could be explained by infection transmitted through trade, importation/exchange of contaminated food, population movements and geographic proximity. The findings can be useful in public health to plan more effective preventive measures.

Indexed as

Genetic VariationGenotypeHepatitis AHepatitis A virusBayes TheoremBulgariaGene FlowHumansMolecular EpidemiologyPhylogenyBayesian approachEpidemicEvolutionHAVPhylogenyTyping

Identifiers

PMID42163135
PMCPMC13371287

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.