Another excellent plenary session presentation with some clinically relevant findings for primary care physicians and health promotion teams.
Associate professor Jo-Ann Passmore, from the University of Cape Town where she also heads the Genital mucosal and STI laboratory gave an insightful presentation on the association between genital tract immunity and susceptibility to HIV and STIs. Her group investigated the markers of inflammation on the vaginal mucosal in South African women prior to acquisition of HIV infection. They measured series of inflammatory cytokines and did screening for the STIs.
Interestingly, they found increased levels of pro inflammatory cytokines MIP-1β, MIP-1α which bind to the HIV CCR5 and facilitate entry of the HIV into the target cells. They also reported increased levels IP-10, and IL-8. The risk of HIV acquisition was significantly higher in women with evidence of genital inflammation, defined by at least 5 of the 9 inflammatory cytokines being raised [OR 3.2; 95% CI 1.3-7.9].
Amongst the STIs, Chlamydia was found to be the most inflammatory STI, while Bacterial Vaginosis was also associated with upregulation of the pro inflammatory cytokines.
Another interesting finding from this study was that there was no correlation between increased genital inflammatory cytokines and the plasma inflammatory cytokines. The clinical and immunological relevance of this finding in the context of long term immune activation for those who eventually got infected and the utility of genital inflammatory markers in clinical practice remains to be seen.
Although this study was done in South Africa, The findings further highlight the importance of screening for STIs particularly for all sexually active adolescents and women even in Australian setting. Also for health care providers and health promotion teams working with CALD communities and Sex workers, this is work provide another compelling evidence for ramping up STI testing campaigns in order to reduce the new transmission of HIV and other STIs.