Hepatitis A Virus Infection: Epidemiology, Diagnosis, and Prevention in the 21st Century

Abstract Hepatitis A virus infection (HAV) is an acute infectious disease caused by the hepatitis A virus (HAV). It is primarily transmitted via the fecal-oral route, and the clinical course depends on the patient's age and comorbidities. Treatment is symptomatic, while the most effective form of prevention remains vaccination. This article presents the current knowledge on the epidemiology, clinical course, treatment, and prevention of hepatitis A. Background: Hepatitis A virus (HAV) is an acute infectious disease of the liver transmitted primarily via the fecal-oral route. Despite the availability of effective vaccines, HAV remains a significant public health concern in both low-and high-income countries. Objectives: This article aims to provide an updated review of HAV infection, including its etiology, transmission routes, clinical manifestations, diagnostic methods, treatment strategies, preventive measures, and implications for public health. Methods:The article presents a comprehensive synthesis of current literature, epidemiological reports from Poland and Europe, and WHO/ECDC guidelines, with a focus on diagnostic criteria, disease burden, and vaccination strategies. ResultsHAV infection typically follows a self-limiting course but may lead to serious complications, especially in older adults or individuals with preexisting liver disease. Diagnosis relies on anti-HAV IgM detection, supported by biochemical and, when needed, molecular tests. Treatment is supportive, as no antiviral therapy exists. Prevention through vaccination is highly effective and recommended for high-risk populations. ConclusionHAV remains a globally relevant infectious disease. Surveillance, public health interventions, and universal or targeted vaccination are key to limiting its spread and impact. Improving sanitation and access to immunization in at-risk groups is critical to long-term control. Keywords: Hepatitis A, HAV, acute viral hepatitis, acute liver infection, fecal-oral transmission, public health, epidemiology.