Should badgers be tested for TB prior to vaccination?

Yes.  It is misguided and dangerous to vaccinate against TB without prior testing.  I believe that vaccinating already infected badgers could result in the emergence of a new stronger strain of the disease.  Also, these already infected and vaccinated badgers will continue to infect other animals, and their future cubs could be born with the disease and the cycle will continue.

TB has remained a major problem in many Third World Countries even though they have been fully implementing the World Health Organisation (WHO) TB vaccination program for decades.  All babies are vaccinated against TB without prior testing.  Therein lies the problem, that babies born with congenital TB are vaccinated instead of being treated.  On the other hand, polio has been eradicated in countries which fully implement the WHO vaccination program.  This program also vaccinates without prior testing.  However, the enormous difference is that polio is an obvious disease, is easily seen and the babies are treated not vaccinated if they have the disease.  TB is not an obvious disease.  It does not become obvious until it is quite advanced and that usually takes a long time.