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25 April 2012

She warned the world of Mad Cow Diseases


//25 Apr 2012
Wendy Grant, who has died aged 89, was a neuropathologist who became one of the first scientists to warn the public that BSE, also known as Mad Cow Disease, could be incubating in the human population.
The disease was first identified in cows in the England in 1985. Two years later government scientists suggested the most likely source was cattle feed made from the remains of dead sheep with scrapie, a similar brain disease.

In 1988 John MacGregor, then agriculture minister, imposed a ban on cattle feed derived from dead animals.

A month before the ban came into force, however, a junior doctor, Tim Holt, became the first to suggest, in an article in the British Medical Journal, that BSE might pose a significant threat to human health, after he and a colleague discovered that some butchers were selling cow brains for human consumption. He suggested that the use of brains in British food should be banned.

Wendy Grant, a retired consultant neuropathologist and an expert in slow viruses (associated with diseases with long incubation periods of months to years) was alarmed by Holt’s piece, particularly when she discovered, through slaughterhouse workers, that cattle brains were being added to meat products such as pies, pâtés and stock cubes.

As one of the few people to have read the literature on scrapie and the human equivalent, Creutzfeldt-Jakob disease (CJD), she realised that government assurances about BSE, “namely ’we have lived with scrapie for two and a half centuries and it has not done us any harm’,” were based on the false premise that cattle brains and sheep brains were dealt with in the same way at abattoirs, “which they obviously were not”.

Humans, she argued, had not been seriously exposed over the centuries to the scrapie agent as sheep brains are seldom removed to be eaten. But when she wrote to the government pressing the need for an inquiry into the dangers of contamination, she was ignored.

Only after she appeared on the BBC in 1989 warning on the dangers of infected cattle tissues the government in response to growing public concern imposed a ban on the use of offal in baby foods.

Influential article
In an article Wendy Grant accused the government of using baby foods “to divert the public from thinking about other foods and thus to imply they are safe, which they are not”.

The official inquiry into the BSE scandal later identified her article as one of the influences that drove the government towards the decision in November 1989 to ban the use of cows’ brain and spinal cord for human consumption.

As ministers and the food industry battled to reassure consumers that British beef was “perfectly safe” and that eating it carried “no conceivable risk”, Wendy Grant, like other scientists involved, found herself the victim of a smear campaign, treated with hostility by Ministry of Agriculture officials and accused of being “out of date”.

But she refused to go away.

In 1994 she described it as “incomprehensible” that the brains of calves under six months old were still being allowed into the human food chain and called for an immediate ban: “We should not be eating the offal even from calves, because we do not yet know whether the disease is passed from mother to calf,” she said. Two years later government scientists confirmed that cows could indeed pass on BSE to their calves.

Creutzfeld-Jakob disease
The turning point came after the first recorded death from what was later described as new variant Creutzfeldt-Jakob Disease (vCJD), on May 21 1995.

Within a year 10 cases had been identified and on March 20 1996, the UK Health Secretary Stephen Dorrell made the announcement that these cases were most probably linked to the consumption of BSE-infected beef or beef products.

In June, in the face of a worldwide ban on exports of British beef imposed by the EU, the government agreed to implement a more thoroughgoing slaughter programme and more effective removal of potentially infective materials from carcases.

Since vCJD was first reported in 1996, a total of 217 patients from 11 countries have been identified. Altogether, since the disease became notifiable in 1996, 176 people in Britain have died from the disease, but uncertainties relating to the potential length of the incubation period complicate predictions of the future number of cases.

Helen Grant, always known as Wendy, was born in Ealing, west London on May 11 1922. She was educated at schools in France, Austria, New Zealand and finally at Bedales, where she became head girl. After taking a degree in Medicine at Cambridge, she did her clinical training at University College London.

She decided to specialise in neuropathology and in 1970 joined the Middlesex Hospital as a consultant. In 1985 she moved to Charing Cross Hospital as a senior lecturer and honorary consultant in neuropathology.

Wendy Grant married, in 1945, Alick Elithorn, but the marriage was later dissolved. She is survived by a son. A daughter predeceased her.

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