A report into the E.coli outbreak at a petting farm which infected 93 people - including a Kent mum's twins published its findings today.

The Independent Investigation Committee's report said many of the families revealed their experiences had been so traumatic they wouldn't take their children to an open farm.

It also recommended the layout of open farms be changed and criticised the Heath Protection Agency for a delay in taking action.

The report added: "Many of the families could not understand why the farm had not closed earlier and did not realise that the HPA did not have the regulatory authority to implement closure.

"They felt this situation required changing."

The independent investigation also criticised the Godstone Farm, saying the outbreak could have been avoided if measures had been taken to limit exposure to animal faeces, which put people at risk of contracting E.coli.

The report was commissioned by the HPA in the wake of the outbreak at Godstone Farm, near Redhill, Surrey, which shut on September 12 last year after visitors were diagnosed with the potentially fatal O157 strain of the bug.

The investigation was led by George Griffin, Professor of infectious diseases and medicine at St George's, University of London.

He said: "This outbreak could very likely have been avoided if more attention had been given to visitors being exposed to animal faecal matter.

"Once it had started, there is no doubt that, even with prompt action, this would have been a big outbreak.

"Nevertheless there was a lack of public health leadership by the Health Protection Agency and a missed opportunity to exercise decisive public health action and thereby restrict the size of the outbreak.

"The assessment of risk carried out by Godstone Farm was inadequate and it principally relied on the actions of the public, primarily through hand-washing, to control the risks."

Speaking after the launch of the report, the HPA's chief executive Justin McCracken said: "The report makes clear that many factors contributed to this incident, including the fact that the HPA should have acted more quickly in this instance.

"HPA responds effectively to thousands of such outbreaks and incidents each year but of course is very sorry for its part in what happened at Godstone.

"That is why I publicly apologised to parents at the time.

"I am determined that the HPA will work with the other bodies to prevent a similar situation developing in future.

"We will act immediately upon all the recommendations in the report which relate to the agency alone and we will work closely with other bodies (including industry, local authorities, the Health and Safety Executive and government departments) to see how best to progress the other recommendations.

"Professor Griffin has also recommended that a multi-agency implementation committee is set up, co-ordinated by the HPA, to ensure the report's recommendations are taken forward and I will ensure the agency plays its full part in this."

Charley May, who heads the Countryside Alliance campaign for outdoor education, said the report was a "knee-jerk" reaction.

He said: "The E-coli outbreak at Godstone farm was traumatic for all involved and the Countryside Alliance offers sympathy to all affected.

"Whilst the severity of the outbreak must be recognised, we also need a proportionate response, and a knee-jerk ban on enabling members of the public to interact with farm animals would be just that."

Yesterday, a Kent mum whose twins were left hospitalised by the outbreak revealed she is among the families preparing to launch a group legal action.

Tracy Mock, of Paddock Wood, whose two-year-old twins spent weeks in hospital fighting the bug following a visit to the farm, said: "The main reason for taking the legal action is that I feel it should be investigated; how it was handled.

"There could be a lot to learn, there are a lot of questions relating to it.

"If they had acted quickly enough we probably would not have gone to the farm."

Her son, Aaron Furnell, suffered acute kidney failure and has to be taken to the Evelina Children's hospital in London every six weeks for blood and urine tests.

He still uses a feeding-tube for ingesting liquids.