GUINEA PIG (CAVIA PORCELLUS) CAN BE OR NOT USED AS AN EXPERIMENTAL MODEL TO STUDY HEPATITIS A VIRUS INFECTION

Priorities for new hepatitis A virus (HAV) vaccine include  the existence of susceptible animal models to perform studies of infectivity, pathogenesis, humoral and cellular immunity, cytokine responses, antiviral drugs and vaccine efficacy. Previous study demonstrated that guinea-pigs (Cavia porcellus) appeared useful for studying some aspects of HAV pathogenesis and for testing safety of vaccines. The experimental infection was studied in twelve guinea-pigs inoculated intraperitoneally; four of them with the Brazilian HAV wild strain (HAF-203 accession: GenBank AF268396) (group 1); four received HAF-203 strain adapted to FRhK-4 cells (group 2) and, four uninfected animals inoculated only with medium 199 (group 3). One animal of each group was killed on days 14, 28, 42 and 56 postinoculation. All parameters investigated were normal, including liver histology, serum ALT/AST levels  and absence of RNA HAV in feces or liver samples. The seroconversion, at days 28  and 56 (group 1) confirmed HAV inoculation. However, anti-HAV titer alone did not guarantee immunity or predict susceptibility. We were unable to establish a guinea-pig as model of HAV. DOI:  http://dx.doi.org/10.17525/vrrjournal.v15i1.34