in order to develop a good serological assay you need both gold standard postive and negative controls. With most infectious diseases you can use sera from individuals who have never had the disease as negative controls and people who have contracted the disease as positive controls. For HHV-8, positive controls have always been pateints with Kaposi's sacroma. The result has been that almost all assays can discern these samples with great reproducibility due to the fact that the HHV-8 antibody titers are extremely high. However, since the general population does not have KS, their titers are much lower and the problem becomes how to distinguish between a low titer positive and a true negative sample? What is required is a gold-standard negative for which there is a great debate on how to identify these samples. As a primary HHV-8 infection does not always result in clinical disease it is not possible to identify a negative sample by the lack of clinicalsymptoms. Further, some studies have reported seropositivity among children making their sera not fool proof for being seronegative.

It is my opinion that the lack of a gold standard negative control sera is the biggest problem for the development of a standardized assay. I would suggest that at present the best we can do is to use samples from individuals who are at low risk for KS, seronegative by all of the current assays (ELISAS and IFAs) as well as negative for viral DNA in plasma and circulating PBMCs and finally, negative for HHV-8 specific CTL responses.

Thank you for answering my question, your explanation has helped a lot. I appreciate your time.