Dogs are usually have an intestinal worm called Echinococcus granulosus (or dog tape worm). The dogs excrete eggs of this worm in their faeces. These eggs are then found in their fur. Humans get infection by ingestion of these eggs. Man is the intermediate host. In other words man harbours the larval stage of this worm in the internal organs particularly liver and lungs and sometimes in brain. This is called Hydatid disease. The pet dogs therefore should regularly be dewormed; they should be kept clean; you should wash your hands with soap and water after handling the dog every time. In addition, one may be allergic to the danders and animal hairs. It may precipitate respiratory allergy from allergic rhinitis to bronchial asthma. The persons having these problems should avoid household pets like dogs and cats. Sometimes fungal skin infections may be transmitted through animal hairs. Therefore, the animals should be kept clean, so also the owner!