Contagious diseases are looked upon as the result of the susceptibility of the human system to the attack of germs and microbes. It is the inborn belief of a real Hindu that every tree, plant and animal may be influenced by invisible intelligences with very fine invisible bodies going by the names spirits or devatas. Some of these devatas are beneficent while some are in malevolent. The beneficent deities are quite incapable of doing any harm by nature. If at all they influence human beings, it would be only to do them good. On the other hand, the evil devatas create the epidemic germs that attack children and others causing them unbearable trouble by their presence in the houses.
Good devatas influence the growth of the children in different ways like physically, mentally and morally by their mere presence in a house. Whereas, the bad devatas breed out worms of rotten fruits and thus microbes of epidemics to trouble children and others.
People believe that the evil devatas are simply having their play and enjoyment at the expense of the poor afflicted children and others. Quite ideally therefore they actually wait for the suitable opportunity to get rid of them. Similarly people whose children are attacked with small-pox, measles, etc., try not to anger the devatas behind those diseases but to propitiate them. Medicines and drugs if administered, are considered to displease the devatas who accordingly make the disease more virulent. Hence people are terribly afraid to administer medicines to children. People have found out by experience that gingelly oil heated to fry mustard seed in it, increases the virulence of the smallpox. Flowers, scents, etc., also make the patients worse. So when there is a case of small-pox in a house no gingelly oil should be heated to fry mustard to flavour vegetables with. No inmate of the house should anoint his or her body with gingelly oil. No shaving is permitted in a house containing a case of small-pox.
Sexual intercourse of people in the house would be the cause of greatest injury to the patient. Hence young men and women should be made to be very careful and guarded, not only to save the patient from harm but also to save him from loss of eyesight. The loss of eyesight is considered most common after a virulent attack of small-pox
A particular period of time is patiently waited to elapse even after the disease is cured. After this the deity is properly worshipped and sent off in a manner supposed to be befitting her dignity.
Another noteworthy feature is that rice, etc., are not to be bestowed in charity from an infected house. This is perhaps due to the fear that the beggars might be impure. It may also be done with the intention that the contagion may not be carried through grain, food, etc., bestowed in charity
After a patient is cured and the scabs formed have fallen off which generally takes place on the twenty-first day after the attack, the goddess is not sent off for some days more.