Improvement of Procedure for HAV Detection in Bottled Water

Abstract

Hepatitis A virus (HAV) is responsible for around half of the total number of hepatitis infections diagnosed worldwide. HAV infection is mainly propagated via the fecal–oral route, and as a consequence of globalization, foodborne outbreaks are reported with increasing frequency. A future standard (CEN/TC 275/WG6/TAG4) for norovirus and HAV detection in food will consider bottled water as a food product; therefore, a validated method for routine monitoring of HAV in bottled water is required. In this study, we describe the validation of a procedure to monitor and quantify HAV in bottled water samples by real-time RT-PCR. Initial experiments focused on evaluating the elution conditions suitable for HAV release from positively charged membrane. Finally, elution with 50 mM glycine and 1 % beef extract (pH 9.5), using an ultrasound cleaning bath, and concentration by ultrafiltration were the methods selected to evaluate HAV detection limit in different types of bottled waters. The HAV detection limit was determined between 0.2 and 20 TCID₅₀/L of bottled water depending on the composition of the bottled water, which highlights the importance of evaluating different types of bottled waters when a method has to be standardized.