And in case if you are bitten by a black widow or a brown recluse, there are chances of some poisonous reactions to venom. You need to visit the doctor as soon as possible. You might be hospitalized as well, depending on the severity of the spider bite. There are also many deaths associated with spider bites. If there is too much spider infestation at your home, it is better to get help from professionals by hiring spider pest control services. While most spiders are not harmful, some spiders like the black widow can deliver venom that can cause severe damage to the body and cause medical issues.