NEW MICROBIOLOGICA, 36, 331-344, 2013 Zoonotic transmission of hepatitis E virus in industrialized countries Franco Maria Ruggeri 1 , Ilaria Di Bartolo 1 , Eleonora Ponterio 1 , Giorgia Angeloni 1 , Marcello Trevisani 2 , Fabio Ostanello 2 1 Istituto Superiore di Sanità, Deptartment of Veterinary Public Health and Food Safety, Rome, Italy; 2 Deptartment of Veterinary Medical Sciences, University of Bologna, Ozzano dell’Emilia, Italy INTRODUCTION Hepatitis E is an infectious viral disease with clin- ical and morphological features of acute hepati- tis. The etiological agent is the hepatitis E virus (HEV), first identified in the early 1980s (Emerson and Purcell, 2003). The disease is an important public health concern in developing countries where it is frequently epidemic (Aggarwal, 2011). Industrialized countries were previously thought to be free from HEV, with a limited number of cases reported only in people who had travelled to endemic areas. However, more recent studies have documented a number Corresponding author Fabio Ostanello Dipartimento di Scienze Mediche Veterinarie Alma Mater Studiorum Università di Bologna Via Tolara di Sopra, 50 40064 Ozzano dell’Emilia, Bologna, Italy E-mail: fabio.ostanello@unibo.it of sporadic cases in developed areas, including Europe, among patients who had no history of travelling to hepatitis E endemic countries. Furthermore, a high anti-HEV seroprevalence has been detected in a significant proportion of healthy individuals of non-endemic countries (Aggarwal and Jameel, 2011). Since the early 1990s, serological evidence of HEV infections and virus detection have been re- ported in many animal species both in developed and developing countries, suggesting the possi- bility that these species may become infected with HEV-like viruses (Emerson and Purcell, 2003). In 1997, a swine HEV strain was identified for the first time in the USA. The swine HEV strain resulted genetically correlated to two human HEV strains detected in the USA in the same pe- riod from patients who had not travelled to en- demic areas (Meng et al., 1997). Since then, swine HEV strains have been detected across the globe. Frequently, a strict genetic correlation between human and swine strains from the same geo- Hepatitis E is an infectious viral disease with clinical and morphological features of acute hepatitis. The disease rep- resents an important public health problem in developing countries, where it is often related to outbreaks mainly as- sociated with consumption of contaminated water. During recent years, an increasing number of sporadic cases have also been described in industrialized countries. Besides humans, the hepatitis E virus (HEV) has also been identified in animals. In 1997, the virus was first detected in swine, and is now considered ubiquitous. Human and swine HEV strains from the same geographical region present a high level of nucleotide identity, and experimental infections have confirmed the cross-species transmission of swine strains to humans and of human strains to non-human pri- mates. Studies on anti-HEV antibodies detection have demonstrated that people working in contact with swine or wild boar have a higher risk of infection than normal blood donors. In Japan and more recently in France, cases of hepa- titis E have been associated with ingestion of uncooked meat from pigs, wild boar, or deer. The disease is currently considered an emerging zoonosis. KEY WORDS: Emerging diseases, Hepatitis E, Pigs, Public health, Viruses, Zoonoses. SUMMARY Received July 3, 2013 Accepted August 3, 2013