'20 people of 90 hospitalised have contracted anthrax. Two-thirds of them have the skin form of the disease, which is most straightforward to cure. Picture: Channel 1

Today 90 people, including 54 children, are in hospital following the anthrax emergency on the Yamal Peninsula in northern Siberia. The 20 confirmed cases is a dramatic rise on yesterday's fire of eight.

Numbers of those in hospital also exceed the total of 64 herders and their families who were at the apex of the infection, suggesting that the 'at risk' circle is now wider than the nomads at a camp at Yar-Sale in Yamalski district where the disease was identified.

Russia's chief epidemiologist Lyudmila Volova said today: '20 people of 90 hospitalised have contracted anthrax. Two-thirds of them have the skin form of the disease, which is most straightforward to cure. The others have more complicated intestinal form.'

Natalya Khlopunova, the local governor's spokesperson, said that all those in hospital 'are showing good signs'. Pictures: Press Service of Yamalo-Nenetsk Governor's Office, Yamal Region

The medical crisis was caused after reindeer became contaminated with zombie anthrax bacteria which had been frozen in the Siberian permafrost.

Experts say the anthrax was embedded in a human or reindeer corpse, and that unusually hot summer weather in this Arctic location, awoke the deadly infection which had been dormant since at least 1941, when the last outbreak occurred.

The cause of the anthrax outbreak could have been infected human remains from a local Nenets burial ground. Picture: Znak.com

Almost 2,500 reindeer died from the epidemic in the Yamalo-Nenets autonomous region, an area famed for its high quality venison. A 12 year old boy died on Saturday after eating infected reindeer meat, and drinking blood from the animal, say reports.

His grandmother perished a day earlier, but it is as yet unclear if she was an anthrax victim.

Natalya Khlopunova, the local governor's spokesperson, said that all those in hospital 'are showing good signs. Doctors are monitoring their condition round the clock'.

A 12 year old boy died after eating infected reindeer meat, and drinking blood from the animal. Archive picture showing Nenets family ejoying fresh venison in tundra: Yamal Region

Despite this rare sign of hope, the authorities now have two key concerns. The first is fear for the survival of those now suffering from the intestinal form of the disease.

The second is the deep concern that anthrax could spread to other areas of Russia.

A major operation involving Russia's bio-warfare troops is underway to incinerate at high temperatures the carcasses of the dead infected reindeer. 70 reindeer corpses were 'eliminated' on Tuesday morning.

A key danger is the spread of infected meat, which is the main carrier of the infection. The specific risk is black market meat from poachers. The regional government last night banned the export of any meat, antlers, or skins from the Yamalski district.

A major operation involving Russia's bio-warfare troops is underway to incinerate at high temperatures the carcasses of the dead infected reindeer. Pictures: Vesti.Yamal, Yamal Region

Infectious disease physician Sofia Rusanova said: 'The main task now is to eliminate all the infected meat. Anthrax is not passed from person to person, but only one piece of infected meat can provoke the decease.'

The Russian Emergencies Ministry today announced 'life sustenance camps' with 600 beds for herders and their families displaced because of an evacuation ordered in the wake of the outbreak.

Officials plan to send Mi-26 and two Ilyushin-76 airlifters to regional capital Salekhard, near which the camps will be located. But 16 herders refused to leave their reindeer in the infected areas.