Google on Monday launched a long-anticipated medical records service letting US users store and manage their health care information online.

Amid concerns over privacy, Google said it has built a secure computer platform separate from its search system to host medical records as part of an emphasis on keeping the health information protected.

"We have put in place the firmest privacy policy we can construct," Google vice president of search product and user experience Marissa Mayer said during a press event at the Internet giant's headquarters in Mountain View, California.

"It is our highest level of security."

Google Health has links to pharmacies, clinics and diagnostic labs. The service is free and enables people to have electronic copies of information such as prescriptions, lab test results, hospital stays, and medical conditions stored on Google computers.

Users of the service dictate how the information is shared.

For example, a user could set up a pre-existing relationship with hospital so that in case of emergency, his or her personal medical history could be instantly available to emergency room doctors.

Or, someone planning an exotic vacation could check the vaccinations they have or might need.

"Google, on your behalf, is storing a copy of your records," Google Health product manager Roni Zeiger said after demonstrating the service.

"This is a user controlled database that Google is hosting."

Google said it has crafted protected online connections with a host of major US medical service providers and is open to working with other health care outlets interested in crafting software to join the network.

earlier related report

Hospital destroyed in quake zone back in business — online

A destroyed hospital near the epicentre of a massive earthquake in southwest China was back in business Sunday — online.

A high-tech imaging system went live to link what was the largest hospital in Mianzhu city with the biggest hospital in the Sichuan provincial capital Chengdu, doctors said.

The link enables doctors at the the Mianzhu medical centre — now based in a tent — to seek advice from their colleagues in Chengdu, said Liu Rongbo, one of the doctors operating the system.

"We just began today," Liu told AFP in front of two black-and-white monitors that flashed up computer-aided X-ray images of a chest, a broken leg, and a skull from patients in Mianzhu.

"The hospital in Mianzhu collapsed and all the instruments were inside."

Liu said it is the first time the technology has been called into action during a disaster.

The system took almost two days to set up but the doctors' ability to give input to their colleagues in Mianzhu will save lives, he said.

"They depend on our diagnosis."

Rescuers earlier cited by state media said the death toll in Mianzhu had risen to 3,000. The government has estimated more than 50,000 people died from last Monday's 7.9-magnitude earthquake, China's worst natural disaster in a generation.

Doctors said they can write a report on a console below the image screens and then send it through a special intranet line installed to Mianzhu.

The Picture Archiving and Communication System employs technology from Germany's Siemens company as well as from China, Liu said.