Considering the commonality of arachnophobia in the general population, it should not be surprising to learn that homeowners often contact pest control professionals about indoor spider encounters. In many of these cases, residents want to see all scary-looking spiders eradicated from their home, and if they had it their way, the entire world. After cockroaches, ants and termites, issues with spiders account for the greatest number of calls made to pest control professionals. Most people with a paralyzing fear of spiders are well aware that the eight-legged creatures are largely harmless to humans, but knowing that unsightly arachnids are present within a home can be a source of significant psychological discomfort. However, at least two spider species that frequently invade Massachusetts homes are now considered by many pest control professionals to be dangerous to humans, and enacting pest control strategies to eliminate them from human-dwellings is justified.

Historically, having spiders professionally eradicated from homes has been considered unnecessary unless the invading spiders happen to be recluse or widow species, both of which cannot be found in Massachusetts. The northern black widow happens to be the one exception, as this species’ distribution extends well into Maine and southeastern Canada. That being said, northern black widows are very rarely spotted in Massachusetts homes, although medically harmful bites have been known to occur in the state. The two species that are gaining attention for inflicting necrotic bites wounds are yellow sac spiders and agrarian sac spiders, both of which are aggressive species that often inflict bites to humans within homes.

Yellow sac spiders and agrarian sac spiders are hairless, yellow to tan colored and their long legs allow them to travel rapidly across floors, walls and ceilings. While most bites inflicted by these two spider species will only result in pain and itchy welts, their willingness to inflict bites to humans make them an indoor hazard. The broad-faced sac spider is another common house spider that has been known to inflict medically harmful bites. Back in 2014, a woman in Connecticut had to be hospitalized after sustaining a bite from this species within her home. Bites from broad-faced sac spiders have necessitated the administration of potent antibiotics, and they are considered by many to be the most frequently encountered spider species in Boston homes and apartments, especially during the fall. Other spider species of minor medical importance that are commonly found in Massachusetts homes include wolf spiders, orb weaver spiders, and Parson spiders.

Have you ever had an infection that you believe resulted from a spider bite?