manoochehr makvandi infectious and tropical disease research center, ahvaz jundishapur university of medical sciences, ahvaz, ir iran; research institute for infectious diseases of digestive system, ahvaz jundishapur university of medical sciences, ahvaz, ir iran; virology department, ahvaz jundishapur university of medical sciences, ahvaz, ir iran; infectious and tropical disease research center, ahvaz jundishapur university of medical sciences, ahvaz, ir iran. tel: +98-6113354389, fax: +98-6113361544 niloofar neisi virology department, ahvaz jundishapur university of medical sciences, ahvaz, ir iran davod khalafkhany virology department, ahvaz jundishapur university of medical sciences, ahvaz, ir iran kamyar makvandi school of medicine, ahvaz jundishapur university of medical sciences, ahvaz, ir iran eskandar hajiani gastroenterology and hepatology department, ahvaz jundishapur university of medical sciences, ahvaz, ir iran ali akbar shayesteh gastroenterology and hepatology department, ahvaz jundishapur university of medical sciences, ahvaz, ir iran

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