Not only did that immunization protect Bill from the full effects of the venomous bites, and it is important to say that he did not have a full immunity as one who is newly vaccinated against smallpox might have, but instead the injections provided a very high level of resistance. So high in fact, that most cobra bites did not affect him except for local tissue damage, and coral snake bites were no worse than a bee sting; the killing power of his injections was far greater than what a coral snake could deliver in a single bite. The added-benefit of that immunity was to be able to to help others in a very unique fashion by donating his special blood to 21 snakebite victims, all of whom survived. The farthest he was ever called upon to rescue a snakebite victim was to help a young boy bitten by a tropical coral snake in the jungles of Venezuela. The boy received Bill's blood, he recovered, and Bill was made an honorary citizen of Venezuela.
He also freely shared his stock of commercial antivenin to come to the aid of victims of exotic snakebite here in the U.S. which would occur upon occasion to a reptile importer, hobbyist, or other venom producer. He would never accept offers of reimbursement for donating blood or his own private stock, he was just happy to help any way he could, always.