A young Asian elephant has died at Sydney's Taronga Zoo following a "sudden and acute" battle with herpes.

Zookeepers noticed eight-year-old Tukta had become lethargic and was not eating on Monday.

The veterinary team was called in and suspected she was suffering a case of Elephant Endotheliotropic Herpesvirus (EEHV).

Taronga Zoo said EEHV was present in almost all Asian elephants but it only causes illness when the animals are young.

"Despite the swift action of everyone involved, she tragically lost her fight against the virus later that afternoon," the zoo said in a statement.

Director and CEO Cameron Kerr said the death was like losing a member of the family.

"Our hearts are broken by Tukta's sudden and unexpected loss," he said.

A newborn Tukta has a splash at Taronga Zoo in 2010. ( AAP: Paul Miller )

"She was a much-loved member of Taronga's elephant herd who loved caring for her little brother Jai Dee."

The zoo said the elephant received the best care and expertise available in Australia.

Senior Veterinarian Dr Larry Vogelnest said he immediately suspected EEHV after examining Tukta.

The disease poses no risk to humans but progresses rapidly in elephants and is almost always fatal.

"The virus that Tukta succumbed to is naturally carried by Asian elephants, and occasionally causes disease in elephants, most commonly between one and eight years of age," Dr Vogelnest said.

"There is no vaccine available for this virus, and at present drug treatment is effective only in one third of cases."

Tukta was the first female Asian elephant born at the zoo.

She was born in November 2010, exactly four years after Asian elephants were brought to Sydney for a regional breeding and conservation program.