Hydatid disease is a common but little studied disease in Himachal Pradesh, India. The definite hosts are various carnivores (meat eaters), and dog is the most common host. Sheep, cattle, goats and swine are common intermediate hosts. Humans are infected through faeco-oral route by the ingestion of food and milk, contaminated by dog faeces containing the ova of parasite or direct contact with dogs. Eggs lose their envelop in stomach and embryos are released, which then pass through the gut wall into the portal system and are carried to the liver where most of the larvae are entrapped and encysted. Some may reach the lungs and very rarely some may pass through the capillary filter of liver and lungs and enter into systemic circulation and reach intracranial cavity. Hydatid cyst disease in childhood is still a serious health problem in the rural area. The brain involvement rate varies from 1-2% in hydatid disease. Especially in children, hydatid cysts can grow to enormous sizes, and the cases can remain neurologically intact. Severe headache in childhood should be taken into consideration carefully in our area where hydatid disease is common. It is a big challenge to anaesthesiologist to manage patient intraoperatively
