Tom Dowling was four when he was exposed to a strain of e-coli while on a school trip to Bowman's Open Farm in north London in June 1997. One week later he was in intensive care. He developed serious brain damage and can now communicate only by blinking.

Bowman's Farms and the London Borough of Barnet admitted 95 per cent liability. The 5 per cent concession was given because of the litigation risks. The apportionment of liability between the defendants is unknown.

Of note was the fact that the farm had not carried out risk or COSHH assessments – both basic health and safety precautions.

E-coli 0157 is transmitted by swallowing faecal material that carries the bug. The route is hand to mouth.

Questions were raised over hygiene and the supervision by farm guides. These, we argued, were lacking. Before Tom's visit there had been two cases of e-coli 0157 being contracted by children at the farm.

The local authority had sent circulars to Tom's school warning that additional care should be taken because of the risk posed. This information was not given to the parent helpers nor, we understand, to the teachers on the trip. It would seem that the head teacher had not realised the importance of the information.

It is correct to say that the strain is often found living harmlessly in the gut of farm animals.

But precautions to reduce the risk can be taken. The farm could have closed while safety measures were put in place. This did happen, but only after Tom fell ill. Parents could have been told of the risk and advised how to deal with this.

To say, as one TV reporter suggested, that this case was a "fluke" can only be based on ignorance. I would hope that farms and local authorities will now appreciate the important issues raised and take steps to minimise the risks.

Had informed and appropriate measures been taken by both the farm and the local authority before Tom's visit this tragic case could have been avoided.

Jill Chamberlain is a partner at Reynolds Porter Chamberlain.