Discovery & Stewardship of Narrow Spectrum Antibiotics

APUA board member, Philip Walson, M.D., who is the Editor-in-Chief of Clinical Therapeutics, provided his comments on the recent article, "Optimer Seeks Quick Green Light From FDA for Antibiotic Against Deadly Bug"

It is too early to be sure what the future holds for this new antibiotic, especially compared to much cheaper generic drugs like metronidazole. However, the development of any new antibiotic is welcome and development and commercialization of any so called ``narrow spectrum´´ antibiotics is especially encouraging. The company will now have to convince physicians to adopt a totally new strategy to treating infections; one that includes first making a clear, specific diagnosis and then using a drug designed to treat only the one diagnosed infection and not selecting a ``shotgun´´ approach to all possible infectious agents. If they are successful this should both increase the use of this antibiotic and help to combat excessive, non-specific antibiotic use by training physicians to think differently about the use of antibiotics. This includes considering the development of resistance as a major outcome variable in antibiotic selection. Such thinking can only be welcomed given the rapidly developing rates of multidrug antibiotic resistance which is due at least in part to the overuse of broad spectrum antibiotics.

What does the general public actually know about antibiotics and their activity?

In observance of the ECDC's Antibiotic Awareness Day today, November 18, we asked Dr. Cliodna McNulty, Medical Microbiologist and head of the Health Protection Agency's PCU, to share her thoughts on what the British public knows about antibiotics.

I have been involved in three large household surveys in Britain finding out what the general public think about antibiotics and resistance. The public's attitudes have changed little over the last 7 years. Reassuringly, most of the general public agree that overuse of antibiotics increases resistance, and that antibiotic resistance is increasing. Respondents also know the principles of prudent antibiotic use, as very few disagreed with the statement, "A course of antibiotics should always be completed" and the same percentage didn't agree that "Antibiotics should not be taken unnecessarily."

However, despite many public campaigns the use of antibiotics hasn't changed. A similar number in 2009 to that of 2003 reported having an antibiotic in the past year. Respondents were less knowledgeable about whether antibiotics were active against coughs and colds, viruses, bacterial and our normal flora. A third think that "Antibiotics work on most coughs and colds" and more think that "Antibiotics can kill viruses." This indicates that there are a substantial group of the British public who believe that antibiotics will be of value when they have a cough or cold and are therefore still likely to request antibiotics from clinicians when they have these conditions.

In future antibiotic educational campaigns, it may be better to discuss the need for antibiotics in relation to the severity of infection or syndrome, rather than the type of microbes (be they bacteria or viruses) responsible.

What are your thoughts and ideas?

It's Time to Get Smart About Antibiotics

This guest blog was written by Jean Patel , PhD, D(ABMM), Deputy Director, Office of Antimicrobial Resistance for Centers for Disease Control and Prevention

When I began my career in antimicrobial resistance at the Centers for Disease Control and Prevention (CDC), cephalosporin-resistant Enterobacteriaceae and methicillin-resistant Staphylococcus aureus were the focus of attention . In a few short years, bacterial pathogens have continued to outwit us by changing their genetic make-up enough to survive nearly all antibiotics that might be considered for treatment.

In the past 10 years, carbapenems have been the “drugs of last resort” for Enterobacteriaceae. However, today we have identified carbapenem-resistant Enterobacteriaceae (CRE), which carry an enzyme called the Klebsiella pneumoniae carbapenemase (KPC), in at least 35 states and globally. Most recently, CRE with new mechanisms of resistance (called NDM-1 and VIM) were also identified in the United States.

Now is the time for action. Antibiotics are a shared resource – and becoming a scarce resource. Appropriate use of existing antibiotics can limit the spread of antibiotic resistance, preserving antibiotics for the future.

On November 15-18, 2010, CDC and our partners will observe Get Smart About Antibiotics Week, in an effort to focus attention on improving antibiotic use as a key effort to reduce antibiotic resistance. The U.S. observance will coincide with the European and Canadian antibiotic awareness days, November 18, 2010. In conjunction with Get Smart Week 2010, CDC will unveil its new Get Smart for Healthcare campaign focused on improving antibiotic use in hospitals and long-term care facilities. Improving antibiotic use in in-patient settings can improve cure rates and reduce Clostridium difficile.

Together, we can address this global resistance threat. By leveraging our collective resources towards preserving these vital therapies for the future, we can protect patients and save lives.

Welcome to APUA's new blog, "Superbugs and Drugs"®!

Antibiotics were long considered “miracle drugs,” capable of saving lives from bacterial infections once considered fatal. However, decades of misuse and overuse have led to the emergence of antibiotic-resistant strains of bacteria invulnerable to many of the drugs we have available today. Since 1981, APUA has promoted improved antimicrobial access and more appropriate use with the goal of “preserving the power of antibiotics”®. We accomplish our mission by conducting antimicrobial resistance research, education, and advocacy at the grassroots, national and global levels.

By extending into the blogosphere, APUA experts intend to serve as a global platform to provide insights and provoke your responses on the impact of antibiotic resistance and strategies for improving antibiotic access and use. We will feature entries from the APUA Staff and our Expert Panel, which consists of selected members of our Scientific Advisory Board, APUA chapter leaders, and other experts in this field. We encourage you to join in the discussion.

Thank you,

Kathleen Young, Executive Director and Stuart B. Levy, MD, President

Agricultural, Environmental, and Community Sources of Resistance

A new study from the Johns Hopkins Bloomberg School of Public Health gives further evidence that antibiotic resistance is only just the result of antibiotic use and abuse in human medicine, but that a reservoir of resistance, from farm animals and environmental contamination, is a significant contributor as well. A team of scientists led by Henry D. Kalter examined E. coli samples in more than 500 young Peruvian children, then compared resistance levels to a range of factors in the children's households and communities. The results are published in this month's issue of the American Journal of Tropical Medicine and Hygiene.As would be expected, the children's own use of antibiotics, as well as family member use, was a significant risk factor for their carriage of drug-resistant bacteria. Applying an antibiotic to a population of bacteria selects for the resistant ones to survive, and though these bacteria might not immediately cause disease, they may pass these genes to other species of bacteria, for example through conjugation.

But the authors also found evidence for a transfer of resistant bacteria between food animals and humans - specifically, through market chicken raised with antibiotics. Living in a community with more families raising chickens, as opposed to buying their chicken at a market, was a significant protective factor against children's carriage of resistant bacteria. Market chickens were also significanlty more likely to carry antibiotic-resistant bacteria than home-raised chickens, and presumably transferred this resistance to humans in the community though the food chain or direct contact. Dr. Edward T. Ryan, president of the American Society of Tropical Medicine and Hygiene, explained the study's importance in this respect:

"[The study] improves our understanding of the growing global public health threat of antibiotic resistant organisms, and underscores the critical role that antibiotic use in animals plays in contributing to this threat. The vast majority of the tons and tons of antibiotics ingested each year on this planet are administered to livestock and animals. This study clearly shows that such use comes with a very real cost to human health."

The study also identified a link between environmental contamination with antibiotic-resistant bacteria and increased carriage of resistant E. coli. In fact, as the authors write,

"In these poor communities in a developing country, with inadequate protection of excreta and water, contamination of the environment with antibiotic-resistant bacteria appeared to play at least as great a role in children's carriage of resistant E. coli as did the children's own antibiotic use."

These results corroborate the need for a big-picture approach to addressing antibiotic resistance in both developing and developed nations. The authors cite the intensive use of antibiotics on chickens raised in Peru as a factor contributing to resistance in humans there, but this is hardly an isolated issue - millions of pounds of antibiotics are administered to farm animals every year in the United States, and the presence of an environmental and agricultural reservoir of resistance genes is a threat to the success of antibiotic treatment everywhere.