Some truths about the excessive use of antibiotics in Italian farms

Following his televised declarations about the use of antibiotics in farmed animals and the danger this poses, Roberto Burioni found himself at the center of a constant verbal slaying, coming from numerous associations with direct interests in the Italian livestock industry. This is an obvious reaction, and of course it is legitimate to protect one’s direct interests, including economic ones; However the fact remains that, in the face of incontrovertible EMA data regarding the consumption of antibiotics in European countries normalized with respect to the meat produced, Italy, at least in 2021, was third after Cyprus and Poland, and data available in previous reports indicate that this is no exception. These numbers need an explanation, because for those who, like me, are not in the sector, it is necessary to understand why the veterinary consumption of molecules such as antibiotics is so high in Italy, compared to other countries, even taking into account the type of bred animals; the explanations, like the confounding factors, can be many, but the consumption in tons made in our country compared to the meat produced is an incontrovertible fact, which leads to further considerations, as I will try to illustrate below.

We have already shown many times how, at the microbial level, genetic information is rapidly shared, in a sort of “world wide web” based on the rapid exchange of pieces of DNA and on the selection of useful ones by the receptor cells, also starting from organisms that are phylogenetically, spatially and even temporally very distant (with the acquisition of DNA traits from millions of years old cells, which have passed the test of time due to particular conditions). Now, a new piece is added, one that immediately makes it clear how selection of DNA traits due to localized conditions can literally fly from one corner of the globe to another. In fact, a work has just been published which, starting from data collected in France, has demonstrated how by sampling the clouds, and precisely the water present in them, it is possible to recover a considerable quantity of bacterial cells. This fact, for those who follow these pages, is not particularly new; we have already seen how there are even bacteria adapted to use clouds as a means of transport and long-distance dissemination. In particular, the researchers’ analyzes showed that the samples contained an average of about 8,000 bacteria per milliliter of water, which arrived in the clouds through various processes capable of transforming the environments in which they usually live on the ground into aerosols. The concentrations found varied considerably, from 330 to more than 30,000 bacteria per milliliter of cloud water; moreover, between 5% and 50% of these bacteria were intact, and therefore potentially alive.

The crucial point of the new work, however, is another: by measuring the concentration of 29 different types, the clouds contained, on average, 20,800 copies of antibiotic resistance genes per milliliter of water. In addition, direct oceanic clouds and continental clouds were each found to contain a different profile of antibiotic resistance. This figure, if further confirmed by subsequent studies, is truly significant: in fact, it implies a much more effective and ubiquitous way of spreading antibiotic resistance than hitherto suspected. This diffusion mechanism is such as to lead to an even greater harmonization of practices in different countries: if bacterial DNA, whether in living or dead cells, can spread resistance (and other more or less dangerous traits) to the four corners of the globe by air, this means that what is done in India, for example, is significant for even very distant countries. All the more reason, the great use of antibiotics documented in Italy (considering, in this case, the absolute quantity of antibiotics used for animals) can also put at risk all those countries in the European Union which make a much more moderate use of antibiotics; and the same, of course, applies to countries such as Poland or other large consumers of this type of drug.

So let’s recap: starting from the Ema data, it is possible to identify a high consumption of antibiotics for veterinary use in certain countries, including Italy. This use is undoubtedly connected to the selection of resistances in the most varied bacterial species, due to a simple and well-established law of nature; then due to mechanisms of long-distance diffusion of the DNA of any type of bacterium, and specifically, as demonstrated in the study discussed here, of sequences capable of conferring resistance to antibiotics, the use by the countries that consume the most antibiotics is proportionally the one that puts at greatest risk not only those countries, but the entire community of neighboring nations (at a minimum). And it is very, very difficult to imagine how the veterinary choices of a certain country, made to guarantee the breeding chain and the economy of that country as much as possible, can then justify any damage caused in countries that belong to that chain and those economics will not benefit.