The European Union on Wednesday maintained a calm front as news emerged of a single Holstein on a Washington state farm testing positive for mad cow disease.

The incident, the first of its kind in the United States, triggered a panic reaction around the world as importers moved to slap bans on U.S. beef and shares in American fast food outlets plummeted.

The EU said it was closely following developments in the U.S. but was not considering tightening existing protective measures. "We are keeping a close eye on the situation," European Commission spokeswoman Antonia Mochan told Reuters. "The EU already has protective measures against U.S. beef imports. We think our measures are sufficient at the moment."

Stringent controls already in place

The 15-nation EU, which has considerable experience with the devastating disease also known as bovine spongiform encephalopathy (BSE), has banned for years the import of most U.S. beef because of health concerns over cattle treated with growth hormones.

Most of the existing measures were implemented by Brussels in the wake of the outbreak of mad cow disease in Britain in 1996, which forced a mass culling of cattle in Europe.

"The United States was classified as an 'at risk country' at the time of the United Kingdom crisis and so we've had restrictions on the import of certain beef ... for years now," Mochan told AFP. Mochan also pointed out that U.S. exports to the EU are "not significant" and added that "what we import is top-end, high-quality stuff."

The European beef industry suffered massive losses when mad cow disease broke out there in the 1990s. British farmers slaughtered about 3.7 million cattle to try to stem the BSE outbreak. Since then cases of the disease have been reported in France, Germany, Austria, Finland, Greece and Luxembourg, according to the office of the European commissioner for health and consumer protection.

The illness is believed to cause a form of Creutzfeld Jakob Disease, or vCJD, in humans thought to be linked to eating BSE-infected beef products such as diseased brain or spinal column material. At least 137 people, mostly in Britain, are reported to have died of vCJD, either through eating beef or having received blood or tissue transplants from vCJD patients.

Britain offers help

Given its considerable expertise in dealing with the outbreak, Britain has offered the Americans help in coping with the crisis. Britain’s Department of Environment, Food and Rural Affairs (DEFRA) said it was standing by to aid its U.S. counterparts. "We’re willing to give our advice on the disease if required, based on the knowledge we have," a DEFRA spokesman said.

U.S. experts have also flown a tissue sample of the infected dairy cow to an animal laboratory in England for additional confirmation.

Nightmare for U.S. cattle industry

Experts believe the BSE case will deal a heavy blow to the $27 billion U.S. cattle industry. Japan and South Korea, leading buyers of U.S. beef, have already stopped imports along with South Africa, Singapore, Malaysia, Hong Kong, Taiwan, Russia and Ukraine.

"It is a big deal," Joe Kropf, livestock analyst with Kropf and Consulting told Reuters. "Consumers cut back on consumption and countries, for safety reasons, embargo beef from affected countries."