The Melbourne academic has been in prison for more than 700 days after being convicted of espionage - a charge Australia rejects.

Ms Moore-Gilbert has enough money to buy food and water inside the infamous Qarchak prison, but is closely monitored by fellow inmates everywhere she goes, sources inside the jail said.

Roya Boroumand, executive director of the Abdorrahman Boroumand Centre for Human Rights in Iran, told nine.com.au the Australian prisoner is under watch by two other inmates who report her movements to prison officials.

"It appears that she is followed by a couple of prisoners who report about anyone trying to talk to her."

Ms Boroumand said the prisoners who kept watch on the Australian had been picked by prison authorities.

It appeared Ms Moore-Gilbert had escaped the coronavirus that was sweeping through the inmate population.

The Human Rights' Activists News Agency (HRANA) said the Qarchak Prison - located in a desert region east of Tehran - provides harsh living conditions for its inmate.

An HRANA report said there is severe overcrowding and the jail has no separate rooms for inmates.

It also said prisoners sleep in large, open areas with only 600 beds for more than 2000 inmates, with hundreds left to sleep on the floor.

Diseases such as AIDS and hepatitis are also rife in the prison, the report said.

In December 2019, the US State Department determined that Qarchak Prison met the criteria for "gross human rights violations", describing it as "an environment that enables rape and murder".

Shortly after her transfer there in July, Ms Moore-Gilbert was visited by Australian Ambassador to Iran Lyndall Sach.

Diplomatic officials said she had access to food, medical facilities and books. They said Australia would continue to seek consular access to her.

Ms Moore-Gilbert was sentenced to 10 years' prison in a secret trial on espionage charges rejected by Australia as baseless.

She is a fellow and lecturer in Islamic Studies focusing on politics in the Arab Gulf states, according to her biography on the University of Melbourne's website.