Hello Science in the News members!
We hope that you are feeling well and healthy this February. Because this is the time of year when illness and infection tend to strike the most, we're all interested in how to keep those nasty bugs at bay. We hope that you find the following article helpful as you consider how to maximize the health of you and your family.
Antibacterial products and your health
This time of year staying healthy is a challenge. As you have probably noticed, there is an increasingly diverse array of antibacterial products on the market which claim to help prevent illness. These products include: soaps, laundry detergents, shampoos, toothpastes, body washes, dish soaps and a variety of household cleaning products. The main ingredient in these products is triclosan, or less commonly, triclocarbon. These substances poison an enzyme called “enoyl-acyl carrier-protein reductase” (ENR) that many bacteria need for survival. So to protect ourselves we should all use lots of antibacterial products, right? Maybe not. Here are some things to consider before filling your shopping cart with antibacterial products.
Unlike antibiotics, antibacterial products are not used as medicines for humans or animals, but are found in products like soap, which are used to disinfect surfaces and eliminate potentially harmful bacteria. Although antibacterial products seem like a powerful weapon in the fight against bacteria, a report in the journal Annals of Internal Medicine suggests that antibacterial soaps may not be any more effective at killing germs than regular soap which works simply by encasing bacteria in droplets and allowing them to be easily rinsed away. In this study, regular use of antibacterial soap did not reduce the number of people who experienced vomiting, diarrhea, fever, sore throat, runny nose, cough or skin infections. Importantly, the article notes that while there may be times when the use of antibacterial products is called for, such as when an individual has other infections, in general, these products should be used judiciously. The danger is that their frequent use could lead to the appearance of bacterial strains that are resistant to antibacterials and antibiotics. Before we go into how this might happen, let’s first review how antibiotics work.
Antibiotics fight bacteria in a number of different ways. For example, drugs like Trimethoprim block DNA and protein synthesis in bacteria but not in mammals. Because DNA is essential to life, bacteria that cannot make new DNA will die. Other antibiotics like penicillins, which are produced naturally by the fungus Penicillium chrysogenum, disrupt the bacterial cell wall, a semi-rigid structure that surrounds the bacterial cell providing structure and protection. Human cells do not have cell walls so only the bacterial cells are affected. So, if antibiotics are so good at killing bacteria, why do antibiotics stop working against some bacteria?
Bacteria can divide and grow rapidly. During this process occasional mutations can occur in the bacteria’s genome. If these mutations are stable, they can lead to new bacteria with different characteristics than the parent bacteria. These different characteristics might include resistance to antibacterial products. In the case of triclosan, mutations in the bacterial gene that produces ENR could produce triclosan-resistant bacteria. Since populations of bacteria all compete for survival on the resources available to them, weaker bacteria will die and stronger bacteria will live. So in the presence of an antibacterial, bacteria which have acquired resistance to the drug would be stronger and would quickly outgrow the original population. Luckily, there are many antibacterial drugs available so that when one drug does not work, another may be used in its place. However, this also means that we must constantly make new drugs to combat the growing number of resistant bacterial strains.
If you decide to purchase antibacterial products this winter, one last caveat to consider is that, just like antibiotics, antibacterial products do not kill viruses. Viruses cause the common cold and the flu in addition to a number of other common infections. Hand-washing with soap and water remains one of the best defenses against these illnesses. The Department of Health and Human Services recommends lathering up for at least 20 seconds.
So, as you think about how to combat illness this winter remember that while hand-washing is important for reducing infections caused by both bacteria and viruses,using antibacterial products may not always be necessary and should be used cautiously.
Primary Report
Effect of Antibacterial Home Cleaning and Handwashing Products on Infectious Disease Symptoms; A Randomized, Double-Blind Trial Elaine L. Larson; Susan X. Lin; Cabilia Gomez-Pichardo; and Phyllis Della-Latta Annals of Internal Medicine, 2 March 2004, Volume 140, Issue 5, Pages 321-329.
