Hobo Spider Bite

Hobo Spider Bites Are Dangerous

The hobo spider is thought to be one of a few species of spider in the United States that is harmful to humans. Reactions to its bite have been reportedly similar to that of a brown recluse. Though the tissue damage caused by a hobo spider seems less severe than that from a brown recluse, it is still important to seek treatment if symptoms develop.

Hobo spider bites have been linked to necrotic arachnidism and systemic poisoning. However, uncertainty exists to how well documented the link between necrotic arachnidism and the hobo spider really is. Has it been hobo spiders in all cases?

Symptoms

Necrosis
Many people are aware of this tissue damage, known as necrosis, which can result from the bites of these spiders.

hobo-spider-bite
hobo bite

Blisters
Other symptoms may include a blister at the site of the bite, headache, fatigue, nausea, joint pain, or impaired vision. These can appear 24 to 36 hours following a bite.

Necrotic Arachnidism

Consequences, or sufferings, due to poisoning by a hobo spider are called tegenarism; the name is related to the name tegenaria. Tegenarism is probably the leading cause of spider envenomations in the northwestern USA and Canada, as black widows are not abundant that far north. The effects of hobo spider’s bites are very similar to those of the brown recluse spider, and often people bitten by hobo spiders think they were bitten by a brown recluse spider, although those two species do not coexist in the same geographic regions.

Treatment

If bitten, a victim should seek medical attention and, if possible, take the spider along for identification. The bite of the hobo spider has not been known to be fatal in healthy people.

It is worth mentioning that some scientists and other experts are not convinced that the bite of a hobo spider is harmful. They feel that the evidence of these bites has been circumstantial and that the hobo spider is rarely caught in the act.

Bite Prevention

Outside
Preventing bites by hobo spiders in high risk situations calls for simple, common sense measures. When working in enclosed infested areas, particularly in such places as the crawl spaces beneath mobile homes, wear protective clothing, including long sleeves tucked into gloves, long pants tucked into boots, and coveralls or a jacket with a hood. Rubber bands over pant legs and sleeves will minimize the possibility of a spider running up an arm or leg in a confined situation. Wear gloves when working outdoors in potential habitats such as rock gardens, and when moving wood. Keep bare hands out of places that you cannot see, and do not use bare hands to turn over possible hiding places: Many bites by snakes and spiders occur when the victim uses bare fingers to turn over wood or other objects that conceal the hidden organism.

Inside
Indoors, shake clothing out that has been stored or laid down in spider inhabited dwellings. Exercise caution when moving boxes or other objects that have been stored in basements, cellars or greenhouses within the range of the hobo spider. A significant number of hobo spider bites occur in bed, when the sleeping person inadvertently rolls over or places a limb on the arachnid. In many instances this could be prevented by eliminating the spiders’ means of getting in or onto the bed. Hobo spiders usually get onto beds by climbing bedspreads or other linen which touches, or is very close to the floor; they are not proficient at scaling slick surfaces, such as polished wood or metal bedposts. Keeping the sides and the front of bedspreads at least eight inches above the floor, and keeping beds at least eight inches from walls with porous surfaces, will minimize the possibility of acquiring an unwelcome eight-legged bed partner.

Fact Sheets:
How to Misidentify the Hobo Spider (PDF)
https://s3.wp.wsu.edu/uploads/sites/2061/2014/01/HoboSpider.pdf