Hepatitis E in Italy: 5 years of national epidemiological, virological and environmental surveillance, 2012 to 2016

Abstract

Increasing numbers of hepatitis E cases are being reported in several European countries, including Italy, but the burden of hepatitis E virus (HEV) infection is largely unknown in the latter. To gain a better understanding of HEV epidemiology at national level in Italy, we piloted a strengthened and integrated human (epidemiological and virological) and environmental HEV surveillance system between 2012 and 2016. Over the 5-year period, 169 confirmed hepatitis E cases were identified, with a national annual incidence of 0.72 cases per 1,000,000. Of 65 HEV-RNA positive samples of sufficient quality for molecular analysis, 66% were genotype HEV3, 32% HEV1 and 1% HEV4. The most frequent risk factor reported by all HEV3 infected cases, was the consumption of undercooked pork and sausage. For the environmental surveillance, 679 urban sewage samples were collected from 53 wastewater treatment plants and HEV-RNA was detected in 38/679 of the samples. Among these, 25 (66%) were genotype HEV3 and the remaining were HEV1. We demonstrate that autochthonous transmission and environmental circulation of genotype HEV3 is adding to travel-related HEV transmission in Italy. We recommend the ‘One Health’ approach to integrated surveillance, and to include HEV-related messages within health information campaigns focussing on food security.

Detection and Characterization of Hepatitis E Virus Genotype 3 in Wastewater and Urban Surface Waters in Germany

“…In the present study, 15 amplicons (9%) of the WWTP influent samples could be successfully sequenced. Using nested RT-PCR, similar results of 5-13.5% of influent samples positive for HEV RNA were reported from Italy and Spain (Rusiñol et al 2015;Iaconelli et al 2017;Alfonsi et al 2018). For genotyping, samples with virus concentrations steps were most suitable, since 13 amplicons were sequenced from ultracentrifugated or PEGprecipitated samples.…”

“…Most common detection methods are nested reverse transcription (RT) polymerase chain reaction (PCR) or quantitative RT-PCR (RT-qPCR) with or without prior virus concentration steps. In recent years, Italy, Norway and the UK have reported first investigations for a HEV surveillance in sewage (Idolo et al 2013;Myrmel et al 2015;Smith et al 2016a;Alfonsi et al 2018).…”

Stable HEV IgG seroprevalence in Belgium between 2006 and 2014

“…Modelled data correspond with observed variations in HEV IgG seroprevalence in Belgian provinces, although the observational data were not formally powered to detect discrete and statistically significant differences. Regional differences are important in HEV seroprevalence surveys, as previous studies have shown large heterogeneity with high seroprevalence in certain regions and lower in others 4,5,27 . Studies in France and Italy have shown areas of hyperendemicity, with HEV IgG seroprevalence in Southern France upwards of 60%, and 42.4%‐55.3% in Northern and Central Italy.…”

Molecular Characterization of HEV Genotype 3 in Italy at Human/Animal Interface

“…In Italy, only few data are available on HEV subtype circulation in humans. Few studies described the detection of HEV-3 strains in human cases (La Rosa et al, 2011;Romano et al, 2011;Festa et al, 2014;Garbuglia et al, 2015;Lucarelli et al, 2016;Alfonsi et al, 2018;Marrone et al, 2019) and their classification into the HEV-3c and HEV-3e subtype (Festa et al, 2014;Garbuglia et al, 2015).…”