HAV Immunity in Iranian Medical Students

Hepatitis A in the Eastern Mediterranean Region: a comprehensive review

Introduction

With 583 million inhabitants, the Eastern Mediterranean Region (EMR) is a worldwide hub for travel, migration, and food trade. However, there is a scarcity of data on the epidemiology of the hepatitis A virus (HAV).

Methods

The MEDLINE and grey literature were systematically searched for HAV epidemiological data relevant to the EMR region published between 1980 and 2020 in English, French, or Arabic.

Results

Overall, 123 publications were extracted. The proportion of HAV cases among acute viral hepatitis cases was high. HAV seroprevalence rate ranged from 5.7% to 100.0% and it was decreasing over time while the average age at infection increased.

Conclusion

In the EMR, HAV remains a significant cause of acute viral hepatitis. The observed endemicity shift will likely increase disease burden as the population ages. Vaccinating children and adopting sanitary measures are still essential to disease prevention; vaccinating at-risk groups might reduce disease burden even further.

What is the context?

Hepatitis A is a viral liver disease caused by the hepatitis A virus.

It is generally transmitted by ingestion of contaminated food or water or through contact with an infected person.

Disease severity increases with age. Children under 6 years of age are usually asymptomatic, while adults are the most affected.

Limited information exists on the number of cases and transmission of hepatitis A in the Eastern Mediterranean region, which includes 21 countries and Palestine, as defined by the World Health Organization.

What is new?

We performed a literature review to summarize data on hepatitis A disease in the Eastern Mediterranean region over the last 40 years (1980-2020). As information for many countries is scarce or outdated, most of the data is from Egypt, Iran and Saudi Arabia.

We found that:

Hepatitis A virus is the most common cause of acute viral hepatitis.

Hepatitis A exposure varied according to the country’s income level.

Low- and middle-income countries showed a universal immunity to hepatitis A virus, although this is not the case anymore.

What is the impact?

Hepatitis A infections have decreased worldwide. Lower exposure to the virus has led to an increase in the susceptible population (including adolescent and adults).

Hepatitis A vaccination for children and high-risk groups such travelers should be considered in the Eastern Mediterranean region.

Evaluation of testing and vaccination status of healthcare workers in Turkey for hepatitis A: A multicenter study

BACKGROUND

This study aimed to investigate the prevalence of the disease and testing and vaccination status of healthcare workers in terms of hepatitis A infection as well as their awareness. This study is a multicenter descriptive study performed with healthcare workers.

MATERIAL AND METHODS

Testing status for hepatitis A, awareness of the results and vaccination status of healthcare workers were compared.

RESULTS

Of the 12,476 healthcare workers participating in the study, only 65% (8,115 healthcare workers) had awareness of hepatitis A test results. Of the participants, 6,481 (66.3 %) stated that they were not vaccinated against hepatitis A. Vaccination rates against hepatitis A decreased with increasing age (P < .01). The rates of vaccination in all departments where participants worked were above 60% (P < .05). While the rate of protection among those working in departments creating a risk for hepatitis A virus infection was higher, no difference among vaccination rates was observed compared with the other departments.

CONCLUSION

Vaccination of seronegative individuals is the safest way for hepatitis A, which can progress to fulminant hepatitis at advanced ages. It must be aimed primarily to increase the awareness of healthcare professionals and to increase the vaccination rates for hepatitis B and hepatitis A for the prevention of viral hepatitis. In our study, the awareness level was found to be above 50%, and the vaccination level was 35%, which is a rate that must be increased.

Hepatitis A, B and C seropositivity among first-year healthcare students in western Turkey: a seroprevalence study

Background

The risk of viral hepatitis among healthcare students (HCSs) is greater than that among the general population. Therefore, this study was conducted to investigate the seroprevalence of the hepatitis A virus (HAV), hepatitis B virus (HBV) and hepatitis C virus (HCV) among first-year HCSs at a university in Turkey and as a secondary objective, to determine the factors associated with HAV and HBV seropositivity.

Methods

This cross-sectional study was performed in first-year HCSs in Izmir, western Turkey. Data were collected using a self-administered questionnaire including items on sociodemographic characteristics, medical history, and hygiene. A total of 650 HCSs were tested for the HAV, HBV and HCV markers. Categorical variables were compared using the chi-square test. The association between independent variables and anti-HAV seropositivity and anti-HBs seropositivity was assessed by multinomial logistic regression analysis.

Results

The overall frequency of total anti-HAV seropositivity was 34.9%. HBsAg, total anti-HBc and anti-HBs seropositivity were found in 0.3, 1.2 and 93.7% of samples, respectively. All of the HCSs were negative for anti-HCV. Total anti-HAV seropositivity was found to be 1.73 times higher in those ≥21 years old, and it was 1.61 times higher in those who perceived their economic status to be average and 2.75 times higher in those who perceived their economic status to be low. Total anti-HAV seropositivity was found to be 4.37 times higher in those who lived in provinces with intermediate human development index levels. Total anti-HBs seropositivity was found to be 2.48 times higher in those ≤20 years old, and it was 2.13 times higher in those who perceived their economic status to be average.

Conclusions

Approximately two out of three HCSs were susceptible to HAV infection. Since HCSs are at high risk for HAV infection, they should be vaccinated before medical clerkships begin. Our results indicate that there is a high prevalence of anti-HBs seropositivity among HCSs. This result may be largely attributed to the implementation of a successful vaccination program in Turkey since 1998.

Comparison of the Prevalence and Risk Factors of Hepatitis A in 10 to 18-Year-Old Adolescents of Sixteen Iranian Provinces: The CASPIAN-III Study

BACKGROUND

Hepatitis A is a common health concern both in developing and developed countries. Hygienic and socioeconomic parameters deeply impact the prevalence and transmission of this disease. Evaluating the epidemiological distribution and risk factors for Hepatitis A virus (HAV) is necessary for policy makers to improve local and national preventive measures.

OBJECTIVES

The aim of this study was to compare the prevalence of hepatitis A infection in a sample of Iranian adolescents living in different provinces of Iran and to assess its family- and community-related risk factors.

METHODS

In this cross-sectional study, serum samples of 10 to 18-year-old adolescents, who were studied in a national health survey, were examined for anti-HAV antibodies. A total of 2,494 subjects were included from 16 provinces by multistage random cluster sampling. Demographic and socioeconomic factors related to HAV transmission were extracted by valid questionnaires. A multilevel analysis using mixed-effects logistic regression (melogit) was used to evaluate the association of risk factors with HAV infection.

RESULTS

The weighted prevalence of HAV varied significantly across the studied provinces (P = 0.001), ranging from 50.43% in the Fars province to 78.81% in Markazi province. HAV was significantly more prevalent in children whose mothers worked outside of the home (OR, 1.73; 95% CI, 1.14-2.62; P = 0.009).

CONCLUSIONS

The risk of symptomatic HAV infection is considerable in adolescents of all studied provinces; thus, universal HAV vaccination is recommended for all adolescents, regardless of their socioeconomic level. However, the risk is higher in some provinces, which seem to be transitioning from intermediate to low endemicity.

Hepatitis A Virus Infection, Vaccination and Iranian Healthcare Workers

CONTEXT

Hepatitis A virus (HAV) infection is an important public health problem. It is estimated that about 1.4 million cases of HAV infection occur every year worldwide. Non-immune healthcare workers (HCWs) can be at higher risk of HAV infection in comparison to general population and an appropriate preventive method should be considered for them.

EVIDENCE ACQUISITION

For finding related articles, a comprehensive search was performed in Scopus, PubMed and Google Scholar and all appropriate combinations of following keywords were considered; "healthcare provider", "healthcare personnel", "healthcare worker", "nurse" "medical students", "Iran", "Hepatitis A" and "vaccination". Also we did a search in Persian language in Google scholar and scientific information database (SID) to find related Persian literature.

RESULTS

A gradual shift in age of HAV infection has been seen from childhood toward adulthood. Data about HAV seropositivity among Iranian HCWs are very limited. However based on the recent studies, it seems that HAV seropositivity has been reduced among HCWs in comparison with the past. All recent studies have suggested HAV vaccination for HCWs.

CONCLUSIONS

Available limited studies show that Iranian healthcare personnel need HAV vaccination. However, for selecting an appropriate preventive method for this high risk group, more original studies are still needed.