A rare Sumatran tiger attacked a worker at the Topeka Zoo in Kansas today, wounding the back of her head and neck before other staff members were able to coax the animal away with food, officials have said.

The zoo keeper was alert and awake when she was rushed to a hospital, where she was listed in stable condition.

The victim, the primary tiger keeper at the Topeka Zoo and Conservation Center, was in the predator's outdoor habitat when she was attacked, zoo director Brendan Wiley said at a news conference.

Somehow, the 7-year-old male tiger named Sanjiv entered the habitat, which is never supposed to happen when a person is present, Mr Wiley said.

Some visitors saw Sanjiv injure the worker, who suffered lacerations and punctures to her head and neck, and also was wounded on her back and an arm, he said.

After about 10 minutes other staff members were able to lure the tiger into an indoor pen using its food ration, Mr Wiley said.

The zoo was closed for 45 minutes after the attack and its six tigers, including Sanjiv and his four cubs, were kept in their pen. All the tigers except Sanjiv were later allowed back to the outdoor exhibit area.

Zoo officials did not plan any repercussions for Sanjiv.

"Sanjiv this morning did exactly what a tiger would when something comes into his territory," Brendan Wiley said, adding there was "absolutely no consideration to euthanise Sanjiv."

Tigers have killed several workers at zoos over the last few years.

In 2016, a male Malayan tiger killed a worker at the Palm Beach Zoo and Conservation Society in Florida.

A tiger mauled a worker at England's Hamerton Zoo Park in 2017, and last year a zoo worker in the Japanese city of Kagoshima was killed by a tiger, according to media reports.

Sumatran tigers are critically endangered, with fewer than 400 living in the wild, according to the World Wildlife Fund.