PPD tests: done 'em and read 'em by the hundreds
1. Your first "reactive" (not called "positive" anymore) reaction will not be very imprssive unless you are fighting TB vigorously right now.
2. Redness is not the criterium for reactivity, nor is elevation, but induration is.
3. A reactive TB test is not usually an allergy, (almost never ever) but a revelation that your body has antibodies in plenty against TB.
4. Each subsequent test after a reactive one will be more reactive, especially if TB is causing yor antibody titres to rise. Once you are confirmed as "reactive", you should have the chest xray instead.
5. No, testing once or twice "too close together" with modern PPD solution will not cause a "reactive" result unless you are already circulating antibodies.
6. A confirmed (read by a pro) "reactive" test means you almost certainly have TB in your body somewhere, but as in the majority of people with normal immune systems your body is handling it, walling it into a tubercle and sending out antibody "watchdogs". Very most likely will never ever go as far as to cause one cough and therefore extremely difficult to transmit. But if we told everyone who tested "reactive" that they had TB infection, they'd freak.
We don't tell people who have had chickenpox they are herpes carriers but
they are. We don't remind people with successful oral polio immunization that they are carrying "tame"polio in their central nervous system. Don't worry, be happy, get the appropriate tests and seize the day.
PS: I was told health care workers in correctional situations by year twenty of employment had a better than even chance of testing "reactive". I get erythema from the injection medium but no induration, and I've been crowded in with tuberculars lots of times without knowledge, as have we all. We're pretty tough birds!
