Seroprevalence Trends and Molecular Epidemiology of Viral Hepatitis in Croatia

Abstract

Viral hepatitis is a significant cause of morbidity and mortality worldwide. In Croatia, hepatitis B virus (HBV) and hepatitis C virus (HCV) are widely distributed, especially in some high-risk groups such as people who inject drugs (PWID), prisoners, and highly promiscuous groups. The seroprevalence of HBV ranges from 7.0% in the general population to 38.8% in PWID, depending on the region. The seroprevalence of HCV is highest among PWID (29–75.5%) as compared to 0.9% in the general population. Analyzing the distribution of HCV genotypes, no substantial changes in the molecular epidemiology of the two most frequent HCV genotypes (1 and 3) in the past 20 years were observed. However, the predominance of subtype 1b compared to subtype 1a as detected in 1996–2005 was not confirmed in 2008–2015. Hepatitis A virus (HAV) incidence was high in the past with a decreasing trend since the 2000s, except for an outbreak in 2017–2018 as part of the large European outbreak, which was mainly among men who have sex with men. Hepatitis E virus (HEV) is an emerging virus detected for the first time in Croatia in 2012. The seroprevalence of HEV is high among hemodialysis patients (27.9%) and liver transplant recipients (19.3–24.4%). In addition, higher seroprevalence rates were observed in animal-related professions (e.g., veterinarians, 15.2%; hunters, 14.9%). All detected HEV strains belonged to genotype 3.

Seroprevalence Study of Anti-HBs Antibodies in the General Population of Vojvodina, Serbia

“…Seropositivity was significantly higher in one-year-old children (94.5% in 2017) compared to children who received a vaccine against HBV at the age of 12 years (65% in the same year), which might indicate a natural decline in anti-HBs levels over time, as previously demonstrated [ 25 , 26 ]. Data from many studies showed a prevalence of anti-HB seropositivity that was similar to our results and was significantly higher in children, adolescents, and young adults [ 5 , 6 , 27 , 28 ]. The highest coverage of HB vaccination and the highest anti-HBs seropositivity was at the age of 1–4 years.…”

First detection of tick‐borne encephalitis virus (TBEV) in raw milk samples in North‐Western Iran

“…Although it is generally expected that IgG antibodies to TBEV remain detectable for a longer period compared to the virus itself, our study presents a contrasting scenario. This can be attributed to two key factors: The rapid slaughter of animals, which likely restricted the full development of their antibody response, and the seasonal aspect of our sample collection, conducted during summer when TBEV is known to be more active (Blomqvist et al., 2021; Vilibic‐Cavlek et al., 2023). As a result, the virus is detectable primarily during the initial clinical phase, highlighting the importance of using both serological and molecular methods for accurate diagnosis and treatment (Balogh et al., 2010; Grešíková et al., 1975).…”