Antibiotics, one of the world's greatest medical discoveries, are slowly losing their effectiveness in fighting bacterial infections and the massive use of the drugs in food animals may be the biggest culprit. The growing threat of antibiotic resistance is largely due to the misuse and overuse of antibiotics in both people and animals, which leads to an increase in "super-bacteria." However, people use a much smaller portion of antibiotics sold in this country compared to the amount set aside for food animals. In fact, according to new data just released by the Food and Drug Administration (FDA), of the antibiotics sold in 2009 for both people and food animals almost 80% were reserved for livestock and poultry. A huge portion of those antibiotics were never intended to fight bacterial infections, rather producers most likely administered them in continuous low-dosages through feed or water to increase the speed at which their animals grew. And that has many public health experts and scientists troubled.
For years scientists concerned about the threat of antibiotic resistant bacteria in food animal production have been trying to figure out just how much antibiotics producers are using each year. The best they could do was come up with rough estimates. That is because the data was never publicly available, until now.
In accordance with a 2008 amendment to the Animal Drug User Fee Act, for the first time the FDA released last week an annual amount of antimicrobial drugs sold and distributed for use in food animals. The grand total for 2009 is 13.1 million kilograms or 28.8 million pounds. I found the stories covering this revelation interesting, but they did not convey the whole picture. It is important to understand how this amount compares to the total available for people. So, I decided to find out for myself and contacted the FDA for an estimate of the volume of antibiotics sold for human use in 2009. This is what a spokesperson told me:
"Our Office of Surveillance and Epidemiology just finished an analysis based on IMS Health data. Sales data in kilograms sold for selected antibacterial drugs were obtained as a surrogate of human antibacterial drug use in the U.S. market. Approximately 3.3 million kilograms of antibacterial drugs were sold in year 2009. OSE states that all data in this analysis have been cleared for public use by IMS Health, IMS National Sales Perspectives."
3.3 million kilograms is a little over 7 million pounds. As far as I can determine, this is the first time the FDA has made data on estimates of human usage public. Below is a breakdown of the FDA numbers prepared by my colleague, Dr. David Love, also from the Johns Hopkins Center for a Livable Future, which compares the estimated amounts of human usage with food animal usage.studies suggest the high use of tetracycline in food animals, particularly in pigs, has lead to the increased rates of bacterial resistance to the antibiotic, such as Methicillin-resistant Staphylococcus aureus or MRSA.