Age-Specific Seroprevalence of Anti-Hepatitis A Antibody Among 1-30 Years Old Population of Savadkuh, Mazandaran, Iran With Literature Review

Abstract

BackgroundTo determine age-specific seroprevalence rates of hepatitis A virus (HAV) immunoglobulin G (IgG) antibody in Savadkuh district, Mazandaran province, north of Iran, as well as to compare the collected data with earlier seroprevalence studies in the region and Iran in order to draw a proper epidemiological pattern for HAV infection in the country.ObjectivesThis study aimed to assess an age-specific HAV seroprevalence among 1- to 30-yearold people in Savadkuh, a less developed district of Mazandaran province, north of Iran.Patients and MethodsThe study participants were 984 subjects who aged from one to 30 years and were residents of rural and urban areas of Savadkuh. They were selected using cluster sampling method and divided into five age groups: 1-2.9 (316 cases), 3-6.9 (254 cases), 7-10.9 (201 cases), 11-17.9 (115 cases), and 18-30 (98 cases). Anti-HAV antibody was measured by ELISA method. Seroprevalence rates among different age groups and their relationship to residency, educational levels of parents, water supply, and waste water disposal system was analyzed using chi-squared test.ResultsOverall seroprevalence rate was 19.20 % with no significant difference between rural and urban residents. The seroprevalence rates increased significantly with age: from 5.7 % in age group 1-2.9 year to 34.8 % in adolescents, and to 68.4 % among young adults (P < 0.0001); regardless of significant differences in educational levels among parents of residents in two areas it did not affect seroprevalence rates. Findings of this study and reviewing other reports from the region and the country suggest an epidemiological shift towards lower rates of anti-HAV antibody seroprevalence.ConclusionsIt appears that anti-HAV antibody seroprevalence rate has been declining among Iranians and thereby more children would be susceptible to this infection. This would necessitate revising current strategies of preventative measures in Mazandaran and Iran.

The seroprevalence of hepatitis A in Istanbul, Turkey

“…The seroprevalence of HAV in Turkey varies among geographical regions, but most regions have an intermediate endemicity [6,7]. HAV infections can be prevented by immunization and HAV vaccine may be used for prophylaxis [5].…”

“…Since, most infections, especially in children, are subclinical, we can estimate HAV infection prevalence in a population by determination of the anti-HAV antibodies [4]. The distribution of anti-HAV antibody seroprevalence over several age groups can be used as a marker of a useful HAV epidemiologic pattern relating to viral transmission through a community [5]. Serologic studies help to determine the patterns of endemicity which have been identified as low, medium and high.…”

A Seroepidemiologic Study of Hepatitis A in Seven to Eighteen-Year-Old School Children in Birjand: New Concerns and Opportunities

“…Table 3 shows the seroprevalence of hepatitis A in different parts of Iran. In Saffar et al's study on HAV seroprevalence in individuals aged 1 to 30 years in Savadkooh, the data showed that the anti-HAV seroprevalence rate increased significantly with age from 5.7% in the age group of 1 to 2.9 years to 34.8% in adolescents (24). Altogether, studies by Alian et al (16), Mehr et al (17), and Sofian et al (18) in different parts of Iran and on various age groups showed inconsistencies in seroepidemiology of HAV between different age groups and within the same age group of different regions.…”

The Trend of Hepatitis A Epidemiology in Children, Based on Two Studies in the North of Iran

“…Available data documented that the risk of death due to HAV infection in patients with underlying chronic liver disease was 23 times more than those without chronic liver disease (11). On the other hand in recent years, a few studies from developing countries reported a changing trend of HAV epidemiology with shift to intermediate or low endemicity, because of improved sanitary condition and hygiene practices (6,(12)(13)(14)(15). Due to absence of HAV vaccination, Iran was previously considered a country with hyperendemic hepatitis A infection.…”

“…Due to absence of HAV vaccination, Iran was previously considered a country with hyperendemic hepatitis A infection. The studies in Iran indicate that HAV infection is decreasing, especially in children (13,16,17). Based on the obtained information, mass immunization of all children could be suggested, but there are also barriers such as cost and feasibility; therefore, considering these problems, at least vaccination in high risk children, such as those with chronic liver diseases, can be recommended.…”