Age and Gender Trends in the Prevalence of Markers for Hepatitis E Virus Exposure in the Heterogeneous Bulgarian Population

First Insight into the Seroprevalence of Hepatitis E Virus and Associated Risk Factors Among Liver Transplant Recipients from Bulgaria

Introduction: Hepatitis E virus (HEV) infection is caused by viruses belonging to the Hepeviridae family. HEV infection can be self-limiting; however, extrahepatic manifestations may be present. The purpose of the current study was to establish the seroprevalence of HEV among Bulgarian liver transplant recipients (LTRs) and to identify associated risk factors. Materials & Methods: The present study was conducted between April 1, 2023, and October 30, 2023, at the Military Medical Academy, Sofia, Bulgaria. All serum samples were tested for anti-HEV IgG/IgM using HEV IgG/IgM enzyme-linked immunosorbent assay on Dia.Pro (Milan, Italy). Each participating LTR completed a detailed paper-based closed-ended questionnaire regarding the associated risk factors for HEV infection. Results: The study included 73 LTRs with a mean age of 47.0 ± 14.0 years. Anti-HEV IgG antibodies were detected in 25 LTRs (34.2%), including 20 males (37.7%) and 5 females (25%). All participants were HEV-IgM negative. HEV seropositivity rates were higher but not statistically significant in LTRs aged >60 years than in those aged <60 years (40% vs. 32.7%). A significant factor by logistic regression was "high level of education" (odds ratio [OR] = 2.917; p = 0.038). Conclusion: To the best of our knowledge, this is the first seroepidemiological HEV study among LTRs from Bulgaria that found a high seroprevalence (34.2%).

Editorial: Epidemiology and Control of Hepatitis Viruses

Five hepatitis viruses-hepatitis A (HAV), hepatitis B (HBV), hepatitis C (HCV), hepatitis D (HDV), and hepatitis E (HEV)-have a huge impact on human health with their ability to cause acute and often chronic infection [...].

Epidemiological assessment of hepatitis E virus infection among 1565 pregnant women in Siem Reap, Cambodia using an in-house double antigen sandwich ELISA

AIM

This study investigated hepatitis E virus (HEV) prevalence among pregnant women in Siem Reap, Cambodia, by developing a cost-effective, user-friendly in-house enzyme-linked immunosorbent assay (ELISA) for detecting total anti-HEV immunoglobulins (Ig).

METHODS

The in-house ELISA was designed for large-scale screening in resource-limited settings. Its performance was benchmarked against two commercial tests: the Anti-HEV IgG EIA (Institute of Immunology, Co. Ltd) and the Anti-HEV IgG RecomLine LIA (Mikrogen). The in-house ELISA demonstrated a sensitivity of 76% and 71.4%, and a specificity of 94.1% and 98.6%, against the two commercial tests, respectively, with overall agreement rates of 92.4% and 94.3%.

RESULTS

Among 1565 tested pregnant women, 11.6% were anti-HEV positive. Prevalence increased with age, particularly in women aged 35-40 years and over 40 years. No significant associations were found with education, number of children, family size, or history of blood transfusion and surgery, except for the occupation of the family head as a public officer. Of the total anti-HEV positive women, 22.7% had anti-HEV IgM, indicating recent or ongoing infection.

CONCLUSION

The study concluded that the in-house ELISA is a viable option for HEV screening in regions with limited resources due to its high accuracy and cost-effectiveness. It is particularly suitable for large-scale studies and public health interventions in areas where HEV is endemic and poses a significant risk to pregnant women.

Hepatitis E Virus (HEV) Infection Among Immunocompromised Individuals: A Brief Narrative Review

Hepatitis E virus (HEV) is a single-stranded positive-sense RNA virus that belongs to Hepeviridae family. HEV is the most common cause of acute viral hepatitis worldwide. According to the World Health Organization (WHO), there are estimated 20 million HEV infections worldwide every year, leading to estimated 3.3 million symptomatic cases of HEV infection. The WHO estimates that HEV infection caused approximately 44,000 deaths in 2015, which represents 3.3% of mortality rates due to viral hepatitis. In low-income (LI) countries and lower-middle-income (LMI) countries, HEV is a waterborne infection induced by HEV genotype (gt) 1 and HEV gt 2 that cause large outbreaks and affect young individuals with a high mortality rate in pregnant women from South Asian countries and patients with liver diseases. HEV gt 3, HEV gt 4, and HEV gt 7 are responsible for sporadic infections with zoonotic transmission mainly through the consumption of raw or undercooked meat from different animals. Acute HEV infection is relatively asymptomatic or mild clinical form, in rare cases the disease can be moderate/severe clinical forms and result in fulminant hepatitis or acute liver failure (ALF). Furthermore, HEV infection is associated with extrahepatic manifestations, including renal and neurological clinical signs and symptoms. Pregnant women, infants, older people, immunocompromised individuals, patients with comorbidities, and workers who come into close contact with HEV-infected animals are recognized as major risk groups for severe clinical form of HEV infection and fatal outcome. Chronic HEV infection can occur in immunocompromised individuals with the possibility of progression to cirrhosis.

Butchering activity is the main risk factor for hepatitis E virus (Paslahepevirus balayani) infection in southwestern Nigeria: a prospective cohort study

Introduction

Paslahepevirus balayani (Hepatitis E virus; HEV) is an emerging virus that poses as a public health threat. The virus is now reported to be the leading cause of acute viral hepatitis, with a unique impact on African settings. Our aim was to evaluate the prevalence and risk factors for HEV infection in three cohorts (animal handlers, villagers, and students).

Methods

A prospective cross-sectional study was carried out on a total of 752 subjects from southwestern Nigeria. In all individuals, anti-HEV IgG and anti-HEV IgM antibodies were evaluated by using ELISA (confirming positive results via immunoblotting), and serum viral RNA was evaluated by using two RT-PCR assays.

Results

The overall seroprevalence of HEV IgG and HEV IgM was 14.9% (95% CI: 12.5-17.6%) and 1.3% (95% CI: 0.7-2.5%), respectively. We observed the highest seroprevalence among animal contact individuals, with butchers being the population with the highest HEV IgG seroprevalence (31.1%). Similarly, HEV IgM was higher in the animal contact group (2.2%) than in the non-animal contact cohort (0%).

Discussions

Viral RNA was not detected in any of the samples. Butchering was significantly associated with higher HEV prevalence. Although all efforts to prevent HEV in Africa have focused on the chlorination of water, our study suggests that most new infections could currently be linked to animal manipulation. Therefore, education and guidelines must be provided in southwest Nigeria to ensure that animal handling and processing methods are safe.

First Insight into the Seroepidemiology of Hepatitis E Virus (HEV) in Dogs, Cats, Horses, Cattle, Sheep, and Goats from Bulgaria

In recent years, hepatitis E virus (HEV) infection has been found to be widespread among different animal species worldwide. In Bulgaria, high HEV seropositivity was found among pigs (60.3%), wild boars (40.8%), and East Balkan swine (82.5%). The aim of the present study was to establish the seroprevalence of HEV among dogs, cats, horses, cattle, sheep, and goats in Bulgaria. In total, 720 serum samples from six animal species were randomly collected: dogs-90 samples; cats-90; horses-180; cattle-180; sheep-90; and goats-90. The serum samples were collected from seven districts of the country: Burgas, Kardzhali, Pazardzhik, Plovdiv, Sliven, Smolyan, and Stara Zagora. The animal serum samples were tested for HEV antibodies using the commercial Wantai HEV-Ab ELISA kit (Beijing, China). The overall HEV seroprevalence among different animal species from Bulgaria was as follows: dogs-21.1%; cats-17.7%; horses-8.3%; cattle-7.7%; sheep-32.2%; and goats-24.4%. We found the lowest overall HEV seropositivity in Plovdiv district (6.2%; 4/64; p = 0.203) and Smolyan district (8.8%; 4/45; p = 0.129), vs. the highest in Pazardzhik district (21.6%; 29/134; p = 0.024) and Burgas district (28.8%; 26/90; p = 0.062). To the best of our knowledge, this is the first serological evidence of HEV infection in dogs, cats, horses, cattle, sheep, and goats from Bulgaria. We found high HEV seropositivity in small ruminants (sheep and goats), moderate seropositivity in pets (dogs and cats), and a low level of seropositivity in large animals (horses and cattle). Previous Bulgarian studies and the results of this research show that HEV infection is widespread among animals in our country. In this regard, the Bulgarian health authorities must carry out increased surveillance and control of HEV infection among animals in Bulgaria.