The Conservatives have called for health screening for all new immigrants and the creation of a public health commissioner.

Shadow health secretary Dr Liam Fox said the post was vital to put public health issues such as obesity higher up the political agenda.

Under the party's plans the watchdog would have their own civil servants and work in the same was as the chairman of the public accounts committee.

Dr Fox argued that the new commissioner was needed to apply "explicit pressure" on politicians to confront difficult public health issues such as HIV.

The party accused the government of starting "an initiative overload" while at the same time failing to react to "a second Aids wave, largely imported from Africa".

He called for all new immigrants to be forced to undergo screening for infectious diseases.

Dr Fox also claimed ministers had refused to deal with issues such as the rise in other sexually transmitted diseases among young people and a "tidal wave of obesity".

"Labour have woefully neglected public health. The current health debate focuses far too much on the running of the NHS. Public health must not be neglected any longer," he said.

"The UK is currently building up a frightening level of hidden illness. This is creating a huge financial liability for our health care services. With the commissioner reporting to parliament, public health will rightly be put back to the top of the agenda."

The idea was contained in a new Conservative consultation paper "Before it's too late: A new agenda for public health".

Plans to screen immigrants for infectious diseases such as Aids and TB were attacked by the Lib Dems.

"This is an unnecessary, extremist, unethical and unworkable policy which will do little to improve public health and much to damage our economy and the fabric of our society," said Dr Evan Harris.