We’ve talked about cytomegalovirus as a dangerous teratogen and opportunistic herpesvirus, but a recent study suggests that in many patients, CMV might be an important calibrator of your immune system. The study, conducted by Stanford researchers, found that young adults who are seropositive for CMV develop better antibody responses to the seasonal influenza vaccine. They didn’t find this affect in older adults, but they did find that a mouse model confirmed their observation in human subjects.
The most striking serological difference they found in children with latent CMV infections was an elevated level of circulating interleukin-13 (IL-13) and IFN-γ cytokines. They also found that CMV+ patients had higher CD8+ pSTAT1 and pSTAT3 responses to IL-6, especially in the younger cohort, when compared to the CMV− subjects.
It’s possible that CMV also enhances immune response to other vaccines as well: likely chickenpox (since they’re both herpesviruses).