Powassan virus is a tick-borne virus that causes severe disease in humans. There are a few synonyms for this viral disease, including POW virus, Deer tick virus, and Neuroinvasive Powassan virus. It is considered a rare disease, but the incidence of it has increased in recent years. The virus can cause fever, headache, vomiting, and other flu-like symptoms. It can also cause severe neurological complications such as encephalitis, meningitis, and even death. Powassan virus is a serious and potentially life-threatening disease, so it is important to take precautions to avoid tick bites when spending time outdoors in areas where ticks are prevalent.