The Director of Infectious Disease at Massachusetts General Hospital, Dr. Murlene Durand, spoke about antibiotic-resistant bacteria last Wednesday. Durand sought to make students more aware of the problem of resistance and possible solutions.
She explained that 50 million tons of antibiotics are used each year in the United States Furthermore, out of the total number of prescriptions given out each year, one-third of the prescriptions are given unnecessarily, and with the current situation of resistance, this could be dangerous. Bacteria have followed the laws of natural selection and it seems that they are catching up to technology.
According to Durand, sensitive strains of bacteria are being killed off by the incorrect use of antibiotics while the stronger, resistant strains survive and grow. If antibiotics are continually overused or misused, these bacteria grow more resistant until the point where antibiotics don’t work at all anymore.
For instance, with the current AIDS epidemic, HIV/AIDS patients have a perfect environment for resistant bacteria growth. With patients’ dysfunctional immune system, they can kill off only the weaker strains of bacteria, leaving the stronger bacteria strains to proliferate. These resistant bacteria are very dangerous because they become completely or intermediately resistant to many of the antibiotics that we have to treat them.
Another place where resistance is built up is found in livestock populations. Of the 50 million tons of antibiotics used, 40 percent are used in animal feed to promote growth. Durand explained that the low shots of antibiotics that are given to the animals are a perfect breeding ground for antibiotic resistance. The low dosages of antibiotics cause the sensitive strains of bacteria in the bodies of the animals to die while promoting the growth of not only the animal, but also the resistant strains of bacteria. Such resistant bacteria can be passed to humans through contact with animals.
There are hundreds of antibiotics, but they are all categorized into eight groups by their common molecular makeup. If bacteria become resistant to one antibiotic in a group, they become able to fend off other antibiotics in the same group. This becomes a serious problem due to the quick pace of resistance compared with the slow pace of antibiotic production.