The use and abuse of antibiotics

By Jaime Sepulveda and Mary Wilson

It is said in official media that Mexico will have a health system as good as Denmark’s by the end of the sexennium. Let’s take a medical example to measure the distance that separates the two.

Most likely, in the past year you or someone in your family has taken an antibiotic which was almost certainly not necessary. The good news is that the discovery of antibiotics at the middle of the last century has saved millions of people and dramatically increased life expectancy. The bad news is that their abuse has led to increasing worldwide antimicrobial resistance. In Mexico, until a few years ago, antibiotics could be obtained without a prescription. For any severe cold or diarrhea, we would self-prescribe an antibiotic. Now a prescription is required, but many pharmacies offer a “free” consultation with poorly prepared doctors ready to prescribe antibiotics.

Antibiotic abuse has consequences at the individual, community and environmental levels. A person who takes an antibiotic, even when prescribed, may develop allergic reactions. In addition, the antibiotic not only acts at the source of infection, but throughout the body. We have infinitely more bacteria in the intestine than the total cells in the human body. The bacterial flora (microbiome) that normally resides in the intestine is essential for health. Antibiotics kill normal flora in sites such as the intestine and vagina and frequently cause opportunistic infections.

Antibiotics have an afterlife in that they remain biologically active. For example, 60% of Amoxacillin ingested by humans or animals is secreted in urine without changes, reaching the environment. Therefore, the contamination of antibiotics and resistant bacteria thrown into the environment is universal. In China, studies of 18 large east-coast estuaries showed a multitude of active antibiotic residues as well as a large number of resistant bacteria. This is how the impact of individual misuse of antibiotics extends to the community and the environment.

Antibiotics are not only used in humans. In fact, globally, 73% of antibiotics are used to fatten cattle, pigs and poultry for human consumption. China is by far the largest producer and consumer of antibiotics, both for human and animal use. The mass production of birds in overcrowded, unhygienic conditions is possible only because antibiotics prevent and treat infections while promoting growth. In the United States, 9 billion poultry are produced annually. Feeding animals with antibiotics allows profit, but it is an important source of antimicrobial resistance.

Both the use of antibiotics and the resulting resistance to them are increasing. In the last 15 years, global antibiotic consumption grew 40%. The number of deaths from antibiotic-resistant infections in the United States, to take one example, doubled in the last 6 years. There is also the sad irony that the excess use of antibiotics (in humans and animals) in middle- and high-income countries is counterposed to lack of access to them in poor populations. Nearly half a million deaths in Africa were due to lack of access to antibiotics.

It is estimated that 50% of antibiotic prescriptions for infections are unnecessary. We must raise awareness that antibiotics are medical tools of the highest benefit, which we are in danger of losing because of such abuse.

We need new antibiotics to replace those that no longer work. But the pharmaceutical industry has no incentives to invest in drugs given high research costs and relatively low returns. We need, therefore, alliances between governments, universities and industry to subsidize research in this vital field. It is useless to have a great new cancer medicine if the patient dies of a resistant bacterial infection.

Reducing the use of antibiotics in humans and animals is a necessary, but not a sufficient, step. We also need clean water and drainage with environmental treatment and sanitation plants, as well as good hospital practices, to reduce exposure to pathogens and resistant bacteria.

Denmark banned the use of antibiotics for fattening pigs and poultry more than two decades ago. Their use in humans in the Scandinavian country has also seen a marked reduction, thanks to good sanitary practices, high vaccination rates and well-prepared doctors. That is just one of the measures of distance that separates us from Denmark.

This op-ed was originally published in Reforma.