Special Containment Procedures: All containment efforts have been null and ineffective, partial breach of veil has occurred. Level 4 or necessary Foundation personnel are to review PROTOCOL-GAIUS (See Addendum 5158-L4) and follow procedures for coverup.
SCP-5158 is to be monitored and data collected for any significant changes in growth of SCP-5158 and SCP-5158-A, any sudden changes are to be immediately to be brought to the attention of the O5 Council. Individuals affected by SCP-5158 are designated as SCP-5158-A with SCP-5158-A individuals experiencing of more severe signs of SCP-5158 are to be apprehended and taken in for psychological counseling and monitoring until either expiration of subject or subject is no longer affected by SCP-5158.
Class A or B amnestics may be administered for afflicted individuals or family members as necessary.
Description: SCP-5158 is identified as an anomalous global phenomenon that occurs at the start of each new month. It is characterized by SCP-5158-A individual(s) who experiences or displays one or more of the following physical or psychological signs of being affected. Symptoms typically do not start showing until 2-3 days after initial exposure:
- Irrational fear of spiders and/or all arachnids, such as Scorpions, mites, and ticks
- Hallucinations of physical manifestations of arachnids, henceforth known as SCP-5158-B
- Physical injuries such as bite marks that match those of the chelicerae (teeth) of the particular arachnid. This includes the effects of the toxicity of poison within said bite(s), however it is not fatal in 98% of cases, even when measured to be in lethal levels.
- Household display physical signs of arachnid infestation, this could include webs, excess of flies or other species of bugs, burrows, nests that contain hatched egg sacks, etc.
- Loss of mental instability, abnormal behavioral, psychological, and mental patterns. Often apparent in only severe cases of SCP-5158-A subjects.
- Skin lesions, caused by urticating hairs of various tarantula species in SCP-5158-B manifesations.
Victims of SCP-5158 often display mental instability or loss of stability approximately a week after exposure, primarily believed to be the cause of greater frequency of sightings of manifestations. Typically in severe cases, SCP-5158-A are admitted to civilian psychiatric facilities under the guise of insanity.
In order to minimize such cases, any and all individuals that display abnormal mental, behavioral, or social patterns after designated as SCP-5158-A are to be immediately apprehended and taken into Foundation custody for more effective psychological counseling, therapy, and testing.
Addendum 5158 Discovery Notes
Addendum 5158-L4:






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