The Black Huntsman Disease

Explorers of The Black Forest infrequently encounter the Black Huntsman. This spider is small, males reaching the size of a thumb nail and females being about 50 larger, carries a venom that it uses to hunt mammals. The venom cases a combination of disorientation and hyperactivity in the host. 
The odd part of the venom is that once bitten, the mammalian host is also able to produce the venom. The later stages of symptoms of the original infection is the inflammation of the thighs, neck, armpits and groin. Buboes filled with a replica of the of the original venom are raised and are prone to burst. Burst buboes further propagate the disease within mammalian populations. 
Interestingly, it appears the venom is easily able to transfer between mammalian species. 
Additional testing also proves that the venom is extremely nutritious to arachnids. 

Treatement:

Early Stage Intervention:

If the patient has not yet developed buboes there are any number of gastrointestinal purgatives that are able to help pass much of the venom. The course of purgatives should be continued aggressively until symptoms subside. 
If purging is unavailable and the original location of the bite is conducive, local excision can provide benefit. In more advanced cases pursuing amputation of larger areas may be pursued. 

Late Stage Intervention:

Once swelling of the neck, groin, armpits, or thighs has begun purgatives become ineffective. The treatment should switch to providing extremely nutritious food to the patient while lowering their body temperature below 20 degrees. This will likely cause a hypothermic reaction in the patient. It needs to be maintained until small amounts of venom accumulate in the buboes. Lancing the buboes and maintaining clean incision sites that are continuously drained until no more venom accumulates will eventually clear the sites without causing greater damage to the host. 

Destruction of the Venom:

Whether in the spider, the patient, or found in the environment the venom remains potent until it is fully frozen. The oil-like consistency remains liquid until approximately -10 degrees. Once that temperature is reach even thawing the venom does not return it to potency.

Type

Parasitic