The mean age of the population was 40.98??17.10 years (range 11C83 years). 313 were women. Of these, 48 (9.7%) had IgG antibodies against HEV. No significant difference was observed between the sexes (or different age groups) and positive antibody. It has been reported that the prevalence rate of this infection is high in Tehran, which is indicative of the endemic nature of this infection in society. The results of this study are similar to those obtained from the east of Golestan province, Iran but different from those obtained from Isfahan province, Iran. As a high percentage of people are susceptible to the infection in society, it is likely to have the prevalence of an epidemic. A species and is a member of the genus and is placed in the family and in realm [[1], [2], [3]]. HEV is the second most common cause of acute hepatitis in adults and is transmitted through the orofaecal route [4]. Although HEV is the most significant factor in acute hepatitis infection in adult residents of Central Asia, the Indian subcontinent and South East Asia, it is the second leading cause of acute hepatitis infection (after hepatitis B) in the Middle East and North Africa [[5], [6], [7]]. The prevalence rate of HEV infection in developing countries with relatively low levels of health varies from 7.2% to 35%. However, the prevalence rate in developed countries is almost 3% [[8], [9], [10]]. Infection with this virus is usually self-limiting, and its mortality rate is relatively low at around 1%C4%; however, in the case of pregnant women, it increases by approximately 20% [[11], [12], [13]]. HEV has been recognized as a cause of chronic hepatitis, especially in immunocompromised individuals [[14], [15], [16]]. Although the infection may be asymptomatic in a group of people, it may cause clinical disease in another group. Of note, 15C60 days after infection with HEV, symptoms of clinical diseases appear (on average, at 40 days); they appear initially with mild symptoms including restlessness, anorexia, nausea and abdominal pain; subsequently, acute hepatitis appears with symptoms such as jaundice, dark urination, pale stools and hepatomegaly [10,17]. The IgM antibody against HEV is produced in the infected individuals’ sera at the onset of clinical symptoms and is detectable over a period of 2 weeks to 3 months. In the case of infected individuals, IgG antibodies appear later and persist for many years after the virus has disappeared, demonstrating an infection with HEV in the past [18,19]. In regions where the disease is endemic, the infection appears epidemically and endemically. Numerous cases of existing hepatitis E have been reported from Pakistan, Iraq and India [[20], [21], [22]]. Several cases of this disease have also been reported in Iran [23,24]; however, few studies have been conducted on the prevalence of HEV in Iran. Despite the fact that the majority of studies in Iran have been carried out on blood donor groups, there have been few research studies on the seroepidemiology of HEV in the general population in Tehran. Tehran, the capital of Iran, is a large city in the north of the country that has a continental-influenced Hot-summer Mediterranean climate. It is the most populous city in Rabbit Polyclonal to NRIP3 Iran and western Asia and has H4 Receptor antagonist 1 the second largest metropolitan area in the Middle East with population of about 10 H4 Receptor antagonist 1 million in the city and 15 million over the larger metropolitan area of Greater Tehran [[25], [26], [27]]. H4 Receptor antagonist 1 Tehran consists of several various ethnic groups including Iranian Azeris, Baloch, Assyrians, Arabs, Armenians, Georgians, Bakhtyaris, Talysh, Jews, Kurds and Circassians. However, the majority of people in Tehran identify themselves as Persians H4 Receptor antagonist 1 [28]. Studies concerning the prevalence of the virus in the general population help to predict the incidence of gastrointestinal hepatitis epidemics. The aim of this study is to determine the prevalence rate of HEV among different age groups of Tehrani residents over the years 2017C2018. Materials and methods This descriptiveCanalytical study was conducted over the years 2017 and 2018 in the eastern cities of Tehran province including Firoozkooh, Damavand, Pakdasht, Varamin, and the northern and eastern districts of Tehran (Fig.?1). The target population was selected by cluster sampling method from families living in these areas. Questionnaires containing demographic information were simultaneously filled in.