Proverbs 28:22  "He that hath an evil eye hasteth after riches, And knoweth not that want shall come upon him." Yes written in the Bible quite a time ago. Some consider a myth. The evil eye is a human look believed to cause harm to someone or something else. "The supernatural harm may come in the form of anything from a minor misfortune to disease, injury or even death. Folklorist Alan Dundes, in his edited volume "The Evil Eye: A Casebook," notes that "the victim's good fortune, good health, or good looks — or unguarded comments about them — invite or provoke an attack by someone with the evil eye. If the object attacked is animate, it may fall ill. ... Symptoms of illness caused by the evil eye include loss of appetite, excessive yawning, hiccups, vomiting, and fever". Quote from Benjamin Radford @ http://www.livescience.com/40633-evil-eye.html.  
 
 As strange as it sounds, sometimes being too close or around certain people with hidden ill intentions may generate an immediate or after effect such as the need to sleep, abrupt coughing or the feeling of immediate anger. That feeling along with the situation you may be in, ie work, an outing or perhaps a personal moment with someone you barely know can lead to damaging effects of the body, mind and spiritual calibration of oneself. Of course this has not been scientifically proven, however it does leave the question of good vs bad energy, the long term effects and results of how people interact with one another.
 
 Even bad mouthing a person or you bad mouthing them when they're present or not present can have consequential effects either way. See Proverbs 26:2  "An undeserved curse has no effect. Its intended victim will be no more harmed by it than by a sparrow or swallow flitting through the sky." So with knowledge of the evil eye compared to cursing, does the same concept apply? A sorrowful myth or deadly truth?  edited 11-21-2016. As an addendum, below is a PDF article regarding signs and symptoms to this controversial topic.

File credit: Mary Smith

​par·a·sit·ic
[ˌperəˈsidik]

ADJECTIVE

1. (of an organism) living as a parasite:
   "mistletoe is parasitic on trees"
   • resulting from infestation by a parasite:
     "mortality from parasitic diseases"
   • derogatory
     habitually relying on or exploiting others:
     "attacks on the parasitic existence of Party functionaries"