en Diagnostic/screening methods and protocols Diagnostic/screening methods and protocols Original article Original article <strong>Introduction:</strong> Early detection of acute Hepatitis A virus infection (HAV) allows adopting proper treatment measures, rapid recovery, and avoiding side effects. This study compares PCR assay with serology for diagnosing acute HAV infection. <strong>Methods:</strong> Twenty samples from patients presenting clinical symptoms of acute hepatitis were tested for anti-HAV IgM antibodies. Genomic RNA was extracted from IgM-positive samples, cDNA was synthesized and examined for genomic HAV using a specific HAV real-time detection kit and a nested PCR. <strong>Results:</strong> Among 20 sera, 14 were positive for anti-HAV IgM antibodies. The specific real-time PCR and nested PCR showed agreement, and both detected HAV genetic material in 3 out of 14 samples. <strong>Conclusion:</strong> High levels of anti-HAV IgM antibodies do not necessarily indicate acute HAV infection in people presenting clinical symptoms of the disease.&nbsp; Measuring IgM antibody levels alongside molecular detection of virus genome by DNA-based methods assay can lead to an accurate, timely, and reliable diagnosis of active HAV infection. Molecular diagnostic testing, Serological tests, Hepatitis A viruses 82 87 http://jommid.pasteur.ac.ir/browse.php?a_code=A-10-317-1&slc_lang=en&sid=1 Hossein Heydari h_heydari@pasteur.ac.ir 0000-0002-0146-9818 No Department of biology, North Tehran Branch, Islamic Azad University, Tehran, Iran Ahmad Majd ahmad_majd2005@yahoo.com 0000-0003-3707-7581 No Department of Biology, North Tehran Branch, Islamic Azad University, Tehran, Iran Mojtaba Hamidi-Fard mojtaba_hamidifard@yahoo.com 0000-0003-3399-3590 Yes Hepatitis and AIDS Department, Pasteur Institute of Iran, Tehran, Iran & Viral Vaccine Research Center, Pasteur Institute of Iran, Tehran, Iran Golnaz Bahramali bahramali@gmail.com 0000-0002-1762-4907 No Hepatitis and AIDS Department, Pasteur Institute of Iran, Tehran, Iran & Viral Vaccine Research Center, Pasteur Institute of Iran, Tehran, Iran Mohammad Reza Aghasadeghi mrasadeghi@pasteur.ac.ir 0000-0003-2186-0774 No Hepatitis and AIDS Department, Pasteur Institute of Iran, Tehran, Iran & Viral Vaccine Research Center, Pasteur Institute of Iran, Tehran, Iran