Hepatitis E, previously known as enterically transmitted non-A, non-B hepatitis, is an infectious viral disease with clinical and morphologic features of acute hepatitis. The disease was recognized first as a distinct clinical entity in the 1980s, when sera from persons affected during a large waterborne epidemic of viral hepatitis during 1955–1956 in Delhi, India<sup>116 Vishwanathan R. Infectious hepatitis in Delhi (1955–56): A critical study: Epidemiology Indian J Med Res 1957 ;  45 (suppl 1) : 1-29

Cliccare qui per andare alla sezione Riferimenti</sup> and another epidemic in Kashmir were found to lack serologic markers of acute hepatitis A and B.<sup>56 Khuroo M.S. Study of an epidemic of non-A, non-B hepatitis: Possibility of another human hepatitis virus distinct from post-transfusion non-A, non-B type Am J Med 1980 ;  68 : 818-823  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti, 119 Wong D.C., Purcell R.H., Sreenivasan M.A. , e al. Epidemic and endemic hepatitis in India: Evidence for a non-A, non-B hepatitis etiology Lancet 1980 ;  2 : 876-879  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti</sup> The first proof of the existence of a new viral hepatitis agent was obtained in 1983, when viruslike particles were detected by immune electron microscopy in feces collected from a volunteer infected with fecal material from patients who had suspected enterically transmitted non-A, non-B hepatitis.<sup>12 Balayan M.S., Andjaparidze A.G., Savinskaya S.S. , e al. Evidence for a virus in non-A, non-B hepatitis transmitted via the fecal-oral route Intervirology 1983 ;  20 : 23-31

Cliccare qui per andare alla sezione Riferimenti</sup> The disease was transmitted successfully to cynomolgus monkeys that excreted similar viruslike particles in their feces.<sup>12 Balayan M.S., Andjaparidze A.G., Savinskaya S.S. , e al. Evidence for a virus in non-A, non-B hepatitis transmitted via the fecal-oral route Intervirology 1983 ;  20 : 23-31

Cliccare qui per andare alla sezione Riferimenti</sup> The genome of this virus, known as hepatitis E virus (HEV),<sup>90 Purcell R.H., Ticehurst J.R. Enterically transmitted non-A, non-B hepatitis: Epidemiology and clinical characteristics Viral Hepatitis and Liver Disease New York: Alan R. Liss (1988).  131-137

Cliccare qui per andare alla sezione Riferimenti</sup> was cloned in 1990<sup>93 Reyes G.R., Purdy M.A., Kim J.P. , e al. Isolation of a cDNA from the virus responsible for enterically transmitted non-A, non-B hepatitis Science 1990 ;  247 : 1335-1339

Cliccare qui per andare alla sezione Riferimenti</sup> and fully sequenced shortly thereafter.<sup>99 Tam A.W., Smith M.M., Guerra M.E. , e al. Hepatitis E virus (HEV): Molecular cloning and sequencing of the full-length viral genome Virology 1991 ;  185 : 120-131  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti, 104 Tsarev S.A., Emerson S.U., Reyes G.R. , e al. Characterization of a prototype strain of hepatitis E virus Proc Natl Acad Sci U S A 1992 ;  89 : 559-563  [cross-ref]

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The occurrence of the first recorded epidemic of hepatitis E as late as 1955 and the infrequency of this disease in developed countries suggest that hepatitis E is a new, emerging infectious disease. However, several epidemics of enterically transmitted hepatitis with epidemiologic features similar to those of hepatitis E outbreaks occurred in Europe and the United States in the 18th and 19th centuries.<sup>17 Blumer G.B. Infectious hepatitis in the United States JAMA 1923 ;  49 : 230-234

Cliccare qui per andare alla sezione Riferimenti, 28 Cockayne E.A. Cattarhal jaundice, sporadic and epidemic, and its relation to acute yellow atrophy of the liver Q J Med 1912 ;  6 : 1

Cliccare qui per andare alla sezione Riferimenti</sup> It can be postulated, therefore, that HEV infection may have occurred in various parts of the world and only recently has become restricted to certain geographic areas, mostly underdeveloped with poor environmental sanitation.