First, if your husband is "extremely" allergic to wasp venom, then he
should see an allergist, and get de-sensitized. Your health insurance will
probably cover it...

...our policy covered our daughter when she was de-sensitized to honey bee
venom. After the initial episode...where she almost died...we had her
tested. Since I had pulled out the stinger, I knew she had been stung by a
honey bee. The doctor only tested her for honey bee venom allergy, as wasp
venom is a different chemical, and she probably wasn't allergic to that.
She probably developed her allergy by being exposed to venom on my clothes,
and in my truck...without being stung regularly. So, testing her for
allergy to other stinging insects was a waste of time...according to her
allergist.

She is now able to withstand a sting with no reaction.

Mike