Download In the US antibiotic sales increased by 20 pcent in four

In the US, antibiotic sales increased by 20% in four years
The volume of antibiotics used in food-producing animals in the US, whether as
growth promoters or for therapeutic use, has not shown a single dip in four years.
Three quarters of these antibiotics are administered in feed. And in the overwhelming
majority of cases, a veterinary prescription is not required.
Recently, the Food and Drug Administration (FDA) published its report on antimicrobials
sold for use in food-producing animals in the US in 2013, and on the evolution since 2009.
A steady rise over four years
From a European viewpoint, the figures, presented in tons (around 10,000 tons of active
substances, ionophores excluded) are somewhat worrying. In four years, no drop in antibiotic
sales has been observed.
Worse, they continued a steady increase, reaching +20% in four years – even though the rise
was slightly lower (around 3-4%) in 2013 than in the preceding years.
A major drop expected by end 2016
However, the announced ban on antibiotic growth promoters, to enter into force end 2016 at
the latest, is expected to bring down the tonnage for the years 2014, 2015 and 2016.
The FDA published sales figures of antibiotics expressed in volumes (kg) for food producing
animals, which is not an index of exposure. The report does not take into account the weight
of the total animal biomass or the number of animals present in 2013. Nor do the figures take
into account the dosage regimens, which vary from several mg/kg in a single injection to
several hundreds of mg/kg per day for several days or months in the feed.
95 % of the tonnage per os
95% of the volume is intended for oral use: three quarters in feed and one fifth in drinking
water (see figures 1 and 1bis).
Administration in the feed is the only route for which the tonnages increased in 2013 (+10%).
Although drinking water is the route that increased most in four years (+30%), it dropped by
10% between 2012 and 2013.
Figures 1 and 1 bis. Volumes according to the mode of administration
Intramammaries: a sharp drop
In contrast to oral administration, all other routes have decreased substantially.
Injectable antibiotics dropped by 15% in two years, but only represent 4% of the total volume.
Even more surprising, the (relatively small) volumes of intramammary antibiotics decreased
by a factor 2.6 between 2012 and 2013. Did the incidence of mastitis also decrease by a factor
3? Or are the new mastitis treatments more efficient in terms of kg active substances?
97 % without prescription
In the USA, nearly the entire tonnage of antibiotics (97-98%) can be sold without veterinary
prescription (see figures 2 and 2bis).
However, regarding the remaining 2-3% of volumes, sold on prescription, increased even
more (+25-30% in four years) than those sold without prescription (+20%).
Nevertheless, a 10% drop was observed between 2012 and 2013 for antibiotics on
prescription, while in the same period, those without prescription increased by 4%.
Figures 2 and 2 bis. Tonnages according to the legal category
Antibiotic growth factors
In the US, antibiotics are all registered medicines approved by the Food and Drug
Administration (FDA). However, the FDA allows antibiotics to be used either for the
treatment of infectious diseases or as growth factor for use in healthy food-producing animals.
The majority (75%) of the tonnage of antibiotics has a “mixed” indication, both zootechnical
(performance) and therapeutic.
In four years, all antibiotics increased by 20%, whether or not they are intended for
therapeutic use or approved as growth factor.
Nevertheless, in four years, the antibiotics reserved for therapeutic use decreased by 10%
between 2012 and 2013, while an increase was observed during the same period for mixed
use.
Figures 3 and 3 bis. Tonnage by type of use
Announced withdrawal on growth promoters
Since early 2014, the FDA and the pharmaceutical companies are committed to the voluntary
withdrawal of growth promoters in feed over a three-year period, or by the end of 2016 at the
latest. 283 premixes are concerned by the withdrawal of this indication.
All antibiotics that remain on the US market will be reclassified ‘on veterinary prescription’.
These decisions are likely to lead to an important decrease of antibiotics sold in the USA in
the years 2014, 2015 and 2016.
The weight of tetracyclines
The weight of tetracyclines represents two thirds of the tonnage (>6,500 tonnes). They are
mainly used in the feed (>4,500 tonnes) and drinking water (600 tonnes). Their volume has
seen a steady growth of +24% in four years and nearly +10% in a year. The ‘medically
unimportant’ antibiotics (e.g. pleuromutilins, polypeptides...) represent just over 10% of the
tonnage. Their sales remain stable.
The penicillins (e.g. amoxicillin) represent 8% of the volume with a sharp increase over 4
years (+20%) but also an important drop (-14%) between 2012 and 2013 (-14%).
Macrolides (5.4% of the volume) have been relatively steady over the four years, with a sharp
decrease last year (-9%).
Lincosamides (2.3%) beat the record of growth in tonnes in 4 years: +153%.
Cephalosporins (0.3%) also increased, by +41% in four years and +2.5% in 2013 alone.
Most other categories showed an average 20-25% growth in tonnage in four years. Only
sulfonamides (3.7% of tonnage) dropped sharply by 24 over 4 years.
Source:
FDA Annual Summary Report on Antimicrobials Sold or Distributed in 2013 for Use in
Food-Producing Animals.
http://www.fda.gov/animalveterinary/newsevents/cvmupdates/ucm440585.htm
Table. Main results on the sales of antibiotics in the US for 2013.
Source: FDA