The CDC updated its Lyme disease Surveillance Case Definition this year. Their Website states,
NOTE: A surveillance case definition is a set of uniform criteria used to define a disease for public health surveillance. Surveillance case definitions enable public health officials to classify and count cases consistently across reporting jurisdictions. Surveillance case definitions are not intended to be used by healthcare providers for making a clinical diagnosis or determining how to meet an individual patient’s health needs.
Typically, reporting criteria for reportable diseases are very strict to ensure that only cases of the disease in question are being reported. The CDC has always noted that their very strict reporting criteria for Lyme disease should not be used in a clinical setting to determine diagnosis and treatment. That's because it's well known that the rigor of strict reporting criteria can be detrimental in a clinical setting.
Of course, that means nothing when the diagnostic and treatment guidelines authored by the Infectious Diseases Society of America (IDSA) and enforced by the insurance industry, dictate exactly that nobody should be diagnosed with Lyme disease unless they meet the CDC surveillance criteria. Anyone who has been through the Lyme meat-grinder knows that.
So, the disclaimer is just that: a meaningless set of words employed as cover for harmful guidelines. If you continue past the gobbledygook to the "Laboratory Criteria," though, something curious appears. Take a look at "Presumptive laboratory evidence":
Presumptive laboratory evidence:
Positive IgG immunoblot(5), interpreted according to established criteria(3), without positive or equivocal first-tier screening assay.
So you could actually be counted as a presumptive "case" of Lyme disease based solely on a "positive" IgG Western blot, without regard to any first-tier test. Now, look at note number five referenced above:
5. While a single IgG WB is adequate for surveillance purposes, a two-tier test is still recommended for clinical diagnosis.
IF you can get a Western blot without first being tested by ELISA, OR you are tested by Western blot DESPITE a negative ELISA, AND that Western blot comes up positive, they will count you as a "presumptive case" of Lyme disease. Am I the only one who finds it incredibly disturbing that the surveillance reporting criteria have been changed to be LESS restrictive than the clinical diagnostic criteria? Why bother with the disclaimer?
The CDC is perfectly happy to count you as a case of Lyme disease at the same time they deny you a Lyme disease diagnosis and treatment.