Genetic stability of master and working strain used for HAVAX® vaccine production in Vietnam

Tóm tắt

Hepatitis A Virus (HAV) is a single, positive-strand RNA virus that belongs to the Picornaviridae family, genus Hepatovirus. Its genome consists of approximately 7500 ribonucleotides. Infection with HAV can lead to hepatitis A, a short-term but highly contagious liver disease and cause big burden, especially for resource-limited settings. Vaccination against hepatitis A is the most effective prevention and control of viral hepatitis. In Vietnam, HAVAX^®, a formaldehyde-inactivated vaccine derived from the HAV p16 HM-175 strain, is produced by the Company for Vaccine and Biological Production No.1 (VABIOTECH). The production of a vaccine requires the master and working seed systems and one of the requirements of vaccine strain is its genetic stability. However, up to now, the complete genome of HAV strains used in HAVAX^® vaccine have never been identified by the manufacturer. This study investigated the genetic stability of the VABIOTECH HAV working strain by next-generation (NGS) and Sanger sequencing techniques. The complete consensus assemblies of both master and working strains were obtained. Analysis of genetic stability of the working strain compared with its master strain at nucleotide and amino acid levels showed an absolute homogeneity in both coding and non-coding regions ensuring the genetic qualification for the HAVAX^® vaccine production.