Figure 1

CHIKV immunity provides cross-protection against MAYV infection and disease in an immunocompetent mouse model. (a) Virus-specific neutralizing antibody titers (solid bars) and MAYV cross-neutralization antibody titers (empty bars) were determined prior to MAYV challenge. Dashed lines indicate the upper and lower limits of detection (1:640 and 1:20, respectively); (b) footpad swelling were determined daily throughout the study; (c) Viremia was measured daily for four days post-infection. All plotted values in (b,c) are mean ± S.D. Data in (b) were analyzed using a repeated measures ANOVA with a Bonferroni multiple comparison post hoc analysis, and data in (d) were analyzed with a one-way ANOVA with a Bonferroni post hoc analysis. There were no significant differences in percent weight change among groups; however, footpad swelling was significantly different between the PBS (i.e. PBS-vaccinated and PBS-challenged) control and all other groups except CHIKV-99659 and MAYY/IRES. Additionally, viremia was significantly different between the PBS control and all other groups except CHIKV-99659 and MAYY/IRES on days one and two, and EILV/CHIKV, CHIKV-99659 and MAYY/IRES on days three and four. Statistically significant values are denoted by *p < 0.05.