Rabid

"There was a -- whatever you want to call it -- a "rabid" attacking the closet door, and he just died. These things have a shelf life..."

- Sam Winchester

Rabids, named by Sam Winchester, were a new kind of creature created by the Darkness by corrupting humans. The corruption caused a mutation and made their behavior become aggressive, while still having a certain degree of intelligence. They can be cured by exposure to Holy Fire.

History
When the Darkness was released, she swept over the town of Superior, Nebraska where a road crew were infected and turned into Rabids. Some of the road crew attacked and killed a family that were on their way into town before being killed by Deputy Jenna Nickerson. More of the road crew made their way into town where they slaughtered everyone at a nearby hospital and started infecting the town. A few hours after the infection began, Sam and Dean Winchester came to the scene of the family's slaughter and encountered an infected member of the road crew who was still alive. They learned of the situation and went to the hospital where they found the slaughter there and learned that Rabids only have a limited lifespan. After they take the baby Amara from her infected father, Dean promises to get her to safety with Jenna's help while Sam insists on remaining behind to attempt to find a cure for the Rabid infection. As Rabids surrounded the hospital, Sam distracted them while Jenna and Dean made a run for it. In the process, Sam killed a Rabid and got splashed with its blood, infecting him. Now infected, Sam began a search for a cure in earnest, capturing a Rabid that was still capable of speaking for more information. However, Sam's efforts to find a cure were in vain until he remembered that a Reaper named Billie told him that he was "unclean in the biblical sense." Looking up purifications from the Bible, Sam found references to fire and holy oil. Near being consumed by his infection, Sam held a sponge doused in holy fire near his neck, burning away the Rabid infection. Now with a viable cure, Sam lured a group of Rabids into the hospital chapel where he encircled them in holy fire. The proximity to the holy fire cured the Rabids and the group and Sam went on to cure the surviving infected residents of Superior.

Months after the first outbreak, Amara unleashed a new kind of rabid that went on to infect anyone who made contact with the giant fog she sent. Hope Springs, Idaho was hit by this fog, a location Sam and Dean were also investigating at. According to one of the victims, this fog will harm all but Amara and Dean.

The outbreak was stopped by the direct interference of God, who cured all those infected and removed the fog entirely.

Characteristics
Rabids had black veins running across their neck and head, similar to when the Leviathan took control of Castiel's vessel. While they had increased aggression, they do not appear to be mindless, as they have been shown to have enough capacity to drive vehicles. One still retained enough humanity to name his daughter and let her go despite being moments from death. When capturing a Rabid, Sam asked if the Rabid could talk or if he was "too far gone", indicating that they can retain their minds to a degree at least under the infection before losing it completely. They also appear to have a pack mentality, as when Sam was cornered by three of them, rather than go for the kill, two of them held him while a third detected that he had been infected. Another infected person told Sam that rabids can smell other rabids. The mutation had a shelf-life which varied by person, but the infected would die hours after fully succumbing to it. If another rabid was detected, or a newly infected human, rabids would not attack. The rate of infection differed from person to person: one Rabid told Sam that "this thing, it ain't math" and "I've seen some people change fast, some change slow. But in the end we all end up the same: we go psycho and we go boom." The start of the infection happens very quickly as Sam was splashed with Rabid blood and moments later a pack of Rabids sensed him as one of them. As a Rabid's infection progressed, the blackness in their veins was shown to travel from near their shoulder up their neck and face with the further the blackness has spread indicating how far along the infection is. Being "unclean in the biblical sense", rabids could be cured through proximity to holy fire to the point that even being trapped in a circle of it can cure them.

Powers and Abilities

 * Aggression - They are very aggressive and were agitated if there were humans nearby.
 * Infection - They can infect normal humans through contact with their blood. Just being splashed in the face with a Rabid's blood is enough to infect a person.
 * Super Senses - Rabids are able to smell each other and other regular humans who have been just infected.
 * Telepathy - The kind of Rabid appearing in Don't Call Me Shurley share a telepathic link with Amara.

Weaknesses

 * Heart - A shot to the heart killed a rabid.
 * Throat - A slit throat killed a rabid.
 * Shelf life - A few hours after turning rabid, a rabid will die.
 * Holy Fire - Proximity to holy fire will cure a rabid.
 * Electricity - When a rabid received a shock, it could be stunned.

Appearances

 * Season 11
 * Out of the Darkness, Into the Fire
 * Form and Void
 * Don't Call Me Shurley
 * All in the Family

Trivia

 * This is the first monster that Sam has named.
 * The rabids somewhat have similar appearance to humans possessed by Leviathans or angels infected by Leviathans' poisons.
 * Besides vampires, Rabids are the only known monster type to have a cure. Castiel was able to cure Dean of being a Jefferson Starship, but he was powered by 50,000 souls at the time.
 * Despite being created by the Darkness which is pre-biblical, the Bible contains a cure for the Rabid infection. However, as this is a biblical purification, it is likely just coincidence and worked due to the Rabids being "unclean in the biblical sense."