Shitala (Sheetala), also called Sitala is a folk deity,worshiped by many faiths in regions of North India, West Bengal, Nepal, Bangladesh and Pakistan. As an incarnation of Supreme Goddess Durga, she cures poxes, sores, ghouls, pustules and diseases.
One story says Goddess Durga has incarnated as little Katyayani, the daughter of sage Katyayan to destroy all arrogant evil demonic forces of the world, in her real form as Durga, she killed many demons that were sent by Kaalkeya.
A demon named Jwarasur, the demon of fever, started spreading incurable diseases to Katyayani's childhood friends, such as cholera, dysentery, measles, smallpox etc. Katyayani cured the diseases of some of her friends. To relieve the world from all fevers and diseases, Katyayani assumed the form of Shitala Devi. Each of her four hands held a short broom, winnowing fan, jar of cooling water and a drinking cup. With her power, she cured all the children's diseases.
Katyayani then requests her friend, Batuk to go out and confront the demon Jwarasur. A battle ensued between the young Batuk and demon Jwarasur. Jwarasur succeeds in defeating Batuk. Then, Batuk, lying dead, magically faded into dust. Jwarasur was shocked that Batuk disappeared and wondered where he went. Then, what he doesn't know that Batuk has assumed the form of an awful male figure.
This person was three-eyed and had four arms. He held a battle-axe, sword, trident and demon head. He was pitch-black in color. His hair was flowing. Eyes blazed with fury. This figure wore a tiger-skin and a garland of skulls. Batuk assumed the form of Lord Shiva's ferocious form, the terrible Bhairav. Bhairav reprimands Jwarasur and tells him that he is the servant of Goddess Durga (incarnate as Katyayani).
A long discussion ensued but then converted into battle. Jwarasur created many demons from his powers but Bhairav managed to destroy all of them. Finally, Bhairav wrestled with Jwarasur and killed him with his trident.
