there are other things besides HIV that cause low CD4/CD8 Ratio. Also HIV does so because it causes a drop in CD4. In my case the ratio is low because I have elevated CD8. I was first tested for HIV as a young child because I received blood transfusions in 1981.
Just found this interesting information...
"The absolute counts of lymphocyte subsets are known to be influenced by a variety of biological factors, including hormones, the environment, and temperature. The studies on diurnal (circadian) variation in lymphocyte counts have demonstrated progressive increase in CD4 T-cell count throughout the day, while CD8 T cells and CD19+ B cells increase between 8:30 a.m. and noon, with no change between noon and afternoon. Natural killer cell counts, on the other hand, are constant throughout the day.(8) Circadian variations in circulating T-cell counts have been shown to be negatively correlated with plasma cortisol concentration.(9-11) In fact, cortisol and catecholamine concentrations control distribution and, therefore, numbers of naive versus effector CD4 and CD8 T cells.(9) It is generally accepted that lower CD4 T-cell counts are seen in the morning compared with the evening (12), and during summer compared to winter.(13) These data, therefore, indicate that timing and consistency in timing of blood collection is critical when serially monitoring patients for lymphocyte subsets."
http://www.mayomedicallaboratories.com/test-catalog/Clinical and Interpretive/88826