Comparative Study of Different Latent Infections of Herpes Simplex Virus Type I in a Murine Model

This study aims to compare the different latent infections of herpes simplex virus type I in a murine model. One hundred and twenty BALB/c mice were randomly assigned into either of three groups: intravenous inoculation group, ocular abrasion group, and intranasal inoculation group. Six weeks later, the trigeminal ganglia (TG) were removed to detect the expression of HSV-I antigen. HSV DNA in TG was also detected by polymerase chain reaction to confirm latent infection. The rate of HSV DNA in TG detected in the intravenous inoculation group was 18/22 and 22/26 in the ocular abrasion group, both of which were higher than the rate detected in the intranasal inoculation group (18/30). The expression of HSV antigen in TG in these three groups was all negative. Mortality rate in the intravenous inoculation group was 8/30, which was much higher than those of the two other groups. Intranasal virus dripping, cornea abrasion, and intravenous injection can detect latent HSV-I infection in a murine model. Compared to two other groups, the cornea abrasion group showed less severe signs, a quicker recovery rate in acute infection, and higher incidence rate of latent infection. Therefore, it is an ideal method in the presence of latent HSV-I infection.