Siliguri, July 10 (IANS): The encephalitis toll in northern West Bengal went up to 11 on Friday as two more patients died in North Bengal Medical College and Hospital (NBMCH) here, a health official said.

A 40-year-old woman patient succumbed early on Friday to Japanese Encephalitis, while a 27-year -old Indo-Tibetan Border Police personnel perished of acute encephalitis syndrome on Thursday.

The first deaths were reported in May.

Encephalitis, caused due to bacterial or viral infections of the brain, injection of toxic substances or increased complications of an infectious disease and resulting in inflammation of the brain and affecting the patient's central nervous system, had claimed over 250 lives in West Bengal last year.

While the lesser symptoms include headache and fever, the more severe ones cause the onset of mental issues like seizures, confusion, disorientation, tremors and hallucinations.

For JE, while human beings are the dead-end hosts of the virus, pigs act as amplifying hosts that aid in spread of the disease.