The order from the FDA, which comes into effect from 5 April this year, prohibits certain uses of the cephalosporin class of antimicrobial drugs in cattle, pigs, chickens and turkeys.

The FDA says it is taking this action to preserve the effectiveness of cephalosporin drugs for treating disease in humans and prohibiting these uses is intended to reduce the risk of cephalosporin resistance in certain bacterial pathogens.

The FDA stresses that antimicrobial drugs are important for treating disease in both humans and animals. This new order takes into consideration the substantial public comment FDA received on a similar order that it issued in 2008, but revoked prior to implementation.

However, the new order that is now in a consultation period until 6 March only bans cephalosporin drugs at unapproved dose levels, frequencies, durations, or routes of administration and it prohibits using cephalosporin drugs in cattle, pigs, chickens or turkeys that are not approved for use in that species (e.g. cephalosporin drugs intended for humans or companion animals) and also bars the use of cephalosporin drugs for disease prevention.

The order does not limit the use of cephapirin, an older cephalosporin drug that is not believed by FDA to contribute significantly to antimicrobial resistance.

Veterinarians will still be able to use or prescribe cephalosporins for limited "extra-label" use in cattle, pigs, chickens or turkeys, provided they follow the dose, frequency, duration, and route of administration that is on the label.

Veterinarians may also use or prescribe cephalosporins for "extra-label" uses in minor species of food-producing animals such as ducks or rabbits.

Even Congresswoman Louise Slaughter, who is leading a campaign to prohibit the use of drugs that could cause antibiotic resistance in humans, described the FDA move at "a modest first step".

"We're really just looking at the tip of the iceberg," she said.

"We don't have time for the FDA to ploddingly take half-measures. We are staring at a massive public health threat in the rise of antibiotic-resistant superbugs. We need to start acting with the swiftness and decisiveness this problem deserves."

In effect, the FDA is only telling vets what they should already be practising – not to misuse the drugs and only use them for what they are intended.

And perhaps the fact that the FDA has felt in necessary to take this step is more of an indictment on the way that these drugs have been used indiscriminately in the past.