American College of Physicians: Internal Medicine — Doctors for Adults ®

Tuesday, October 8, 2013

Water, hand sanitization and other technologies to avoid spreading sickness

This summer has been full of adventures in and around water, alongside people with and without disease caused by infectious intestinal organisms. It’s been lots of fun, and I dearly yearned not to be slowed down by explosive vomiting and diarrhea. Because of this intense yearning not to feel like crap, I have been doing lots of studying and thinking about both hand hygiene and water purification and have been experimenting with various techniques and technologies.

Most infectious ills of the gut are transmitted by the fecal-oral route. The bacterium, parasite, virus or other unspecified microorganism must make its way from the feces (or sometimes vomit) of the infected person to the mouth of the new host to be ingested, thence to infect and cause disease. For many conditions it does not take many organisms to cause infection, and some of the causative entities can survive outside of a host in pretty unfriendly environments for various amounts of time (up to around 2 weeks for norovirus, for instance.) After having a bowel movement, the hands are the most adventurous parts of the body, in terms of making contact with other people, and so cleaning the hands is the most vital part of preventing person to person transmission.

Water contamination with feces is very common, either from washing or directly depositing the intestinal contents in a place where they can be transmitted by rain or other mechanical means to a water source, or by animals who carry the pathogenic organisms pooping wherever the mood hits them. Thus purification of water is key to preventing the spread of infectious gastroenteritis.

In hospitals hand hygiene is often a matter of life and death. In the years before Ignaz Semmelweis instituted hand sanitization with a cholorinated lime solution in his maternity hospital in Vienna in 1944, death by puerperal fever (infection of the uterus at childbirth) was common. Despite dramatic reduction in deaths due to hand hygiene it has been a slow process getting physicians to clean their hands between patients. With the increase in multi-drug resistant infections and the increase in use of drugs which suppress the immune system in the treatment of cancer and autoimmune diseases, hand hygiene has become even more important as a way to keep the most difficult organisms to treat from finding new hosts in hospitals. Much research has been done to evaluate the practical and theoretical aspects of various ways to clean our hands.

The big controversy with hand hygiene has been between using alcohol based hand rubs and actual hand washing with soap and water. In the early 2000s various articles came out showing that a gel made of a high concentration of alcohol could successfully kill the majority of pathogenic bacteria without requiring that a person actually find water and wash their hands. This was game changing and resulted in the explosion of new products and the installation of hundreds of thousands of hand sanitizer dispensers in hospitals and other public places.

To reap full benefits with these products, the amount of sanitizer must be sufficient to keep the hands wet for 30 seconds. Humans are prone to false economies and so many people will use just a little dab, which is close to useless, and has reduced the practical effectiveness of these things. It also became clear that there were certain organisms which were quite resistant to alcohol, and these were clinically very important. Clostridium difficile, the scourge of the antibiotic treated patient and a common hospital acquired infection is transmitted via spores which are quite alcohol resistant. Hand washing is much more effective for these and chlorhexidine is by far the most effective commonly available soap.

In practice, use of hand sanitizer is much inferior to hand washing in nursing home settings in the control of outbreaks of norovirus, also known as the cruise ship virus. This may be because of inadequate use, but norovirus is also known to be resistant to these products. Soap and water handwashing, however, is also prone to failure because people don’t spend enough time doing it. Twenty to 30 seconds of handwashing is necessary to remove the majority of microorganisms from the hands, and wiping them with paper towels appears also to be important. Recently non-alcohol based rubs have come out, based on either benzalkonium chloride or benzethonium chloride, which are longer lasting and have a broader spectrum of bacterial killing. These will probably replace the alcohol based products.

I am not terribly concerned about the impact on our overall biome with these products since the rest of the skin surface is unaffected and the hands do eventually get recolonized as we touch our arms and faces in normal everyday life. The chemical benzalkonium chloride has been around forever as an antiseptic and so safety is probably not an issue, but I am not totally sure about benzethonium chloride.

While using alcohol based hand sanitizer at a camp with people of various propensities and sensitivities, I was struck by the incredibly strong smell that persisted and so washed my hands after using it. I then realized the totally obvious practical point that it need not be an either/or proposition regarding hand hygiene. When I am not sure which microorganism I am trying to avoid transmitting, I should wash my hands and use hand sanitizer. It just isn’t that difficult. With the alcohol based sanitizers, I should use them first, then wash. With the longer lasting chemical rubs, it would probably be best to use them second. In a water limited setting, like in developing countries, alcohol based sanitizers are clearly superior (see this study) to washing with water, even if the hands are visibly soiled, when they are actually available.

The biggest issue in any situation where these things are necessary is instilling discipline. People are just not very good about washing their hands, especially doctor people. It would be easier if they could really see the impact of not doing it, which is often huge. It would also be easier if it was, in fact, easier, and I just ran into a gadget that fits that description at a barbecue shop in Bend, Ore. A company called Meritech makes a hand washing machine that removes 99%+ of bacteria from the hands in 12 seconds using an automatic dispenser of water and an antibacterial soap. It was strange to find one in this restaurant, but the owner told me she just thought it was an excellent idea. It cost her around $5,000, and it was really fun to use. It felt like a hand massage and eliminated the issue of re-exposing the hands to bacteria when turning off the faucet. If they put these in hospital rooms, I think they would be a big hit.

But on to water purification. My first trip to Haiti was blessedly without intestinal impact. The next one, though, ended very poorly. I developed a fever, nausea, diarrhea then constipation and liver swelling. I couldn’t eat for a month without becoming nauseated. I recovered, at least mostly, but have been very serious about water safety since then. My discomfort clearly sucked, but, more importantly diarrheal disease, mostly caused by water and food contamination, is the second leading cause of death for children under 5 years old and results in the deaths of over 750,000 children every year. It is largely preventable.

The options for eliminating water infection risk are many, and all have pros and cons. Some are new, some are old. I think I know about nearly all of them. To avoid water related disease, we must kill or remove parasites, their eggs, bacteria and viruses. We can use chemicals, filters or radiation to do this. The simplest and oldest effective method of water purification is boiling. If water is boiled for a minute, virtually all microorganisms are killed and it will be safe to drink.

Chlorine is toxic to just about every living thing and a little less than a teaspoon of bleach added to 5 gallons of water and left to sit for 30 minutes (the chlorine molecules must reach all of the intended targets) will be safe to drink. The EPA quotes 8 drops of bleach to sanitize 1 gallon of water. If it is left awhile the chlorine gradually evaporates and the taste improves, though it is not bad at all at this level. One must remember that bleach does lose potency over time, and that these proportions apply to fresh bleach, 5-6% sodium hypochlorite.

Chlorine dioxide is a more potent bactericide than bleach but is harder to find and more expensive. It comes in both tablets and liquid and leaves virtually no chlorine taste. Aquamira is the product I have used. Povidone iodine, the 10% solution that is used as a medical skin prep, is effective at a concentration of 1:1,000, which means 1 mL (15 drops) in a liter of water, when left for 15 minutes. It also doesn’t taste too bad, but will turn purple if mixed with starch, so is quite alarming if used to cook pasta. Tincture of iodine and iodine tablets are more potent but a little harder to come by.

Ceramic filters, like those used for backpacking, remove all but the smallest viruses. Unfortunately hepatitis A and E, which cause lots of bad disease in developing countries, are not removed by ceramic filters and can be present and infectious in water. These filters, like the Katadyn pocket water microfilter and the MSR Sweetwater, are very compact and can be used to remove bacteria and protozoa from huge quantities of stream water, as well as removing undesirables like pine needles and algae and grit. They are absolutely fine for most uses but are not adequate, alone, for places where virus contamination is an issue.

A few years ago a British engineer came up with a super fine filter that eliminates viruses as well and is very simple to use. The name of the company is Lifesaver and it has been marketed to the military and well as being introduced into water limited settings where people drink from puddles with obvious contamination. I got one of these because I was impressed with the demonstration video and could see how it would potentially save lives. They make 750 mL bottles, which I bought, and big multiple gallon jugs which can be filled from any water source, even really nasty ones, and then a low pressure pump pushes the water into a reservoir from which it can be used. The contraption is heavy, about a pound and a half, but tough and easy to use. I used it exclusively in Tanzania and was blissfully without intestinal ills. It costs nearly $200 and is rated to be able to purify 6,000 liters before the filter needs to be replaced. They recommend replacement of the charcoal filter after each expedition, but that is not required for safety.

The most surprising technology to me is ultraviolet (UV) light treatment. UV light has been used for water purification for decades, but recently small pocket lamps have become commercially available which can be used on the fly. Ultraviolet light attacks DNA and RNA, the genetic materials of cells, and kills everything whose function depends on these, which is basically everything. The UV radiation in these devices is very high frequency and depends on the water being nearly completely clear to work. It cannot penetrate particles of poo floating in water. It is an excellent way to treat water from the tap or water that has been filtered or is visibly without particles. UV light is increasingly used to treat city water sources since it doesn’t depend on toxic chemicals to work. It does, however, depend on electricity. I bought a steripen, which is a device about the size of an electric toothbrush, which recharges from a USB port. I also have a solar battery which a USB output so I am set, but some of the pens require rechargable AA batteries which are a little less flexible in resource poor settings. With the pen, you simply press a button on the handle and stir the water in a liter bottle for 90 seconds until the pen indicates the process is complete. Camelback makes a bottle with the UV source built in, also with a rechargeable battery with a USB connection. These contraptions all cost around $100. It is also possible to purify water by placing it in a PET plastic container in full sunlight on a roof for 6 hours, using both the heat and the UV to kill anything living in it.

I’m headed to Haiti and South Sudan in the next 2 months and will bring my Lifesaver bottle and Steripen, with some povidone 10% for backup. I will eat cooked food or fresh fruit that I can peel. I absolutely promise not to drink the delicious glasses of whatever they offer me even if I know they will taste amazing and I am very thirsty (except tea if I see the water boil). That is really the hardest thing. Not eating cabbage salad. Not drinking the glasses of yummy juice punch. I will remember what it was like to be nauseated for a month with a swollen liver. I will use hand sanitizer and then wash my hands, whenever there is water available to do so. In Haiti we will again work on projects to improve waste disposal and promote water purification (bleach treatment is probably the most practical there). My resolve is firm, my research extensive and my experience instructive.

Janice Boughton, MD, ACP Member, practiced in the Seattle area for four years and in rural Idaho for 17 years before deciding to take a few years off to see more places, learn more about medicine and increase her knowledge base and perspective by practicing hospital and primary care medicine as a locum tenens physician. She lives in Idaho when not traveling. Disturbed by various aspects of the practice of medicine that make no sense and concerned about the cost of providing health care to every American, she blogs at Why is American Health Care So Expensive?, where this post originally appeared.

Labels: , , , , , , ,


Post a Comment

Subscribe to Post Comments [Atom]

<< Home

This is a printer-friendly version of this page

Print this page  |  Close the preview




Contact ACP Internist

Send comments to ACP Internist staff at

Blog log

Members of the American College of Physicians contribute posts from their own sites to ACP Internistand ACP Hospitalist. Contributors include:

Albert Fuchs, MD
Albert Fuchs, MD, FACP, graduated from the University of California, Los Angeles School of Medicine, where he also did his internal medicine training. Certified by the American Board of Internal Medicine, Dr. Fuchs spent three years as a full-time faculty member at UCLA School of Medicine before opening his private practice in Beverly Hills in 2000.

And Thus, It Begins
Amanda Xi, ACP Medical Student Member, is a first-year medical student at the OUWB School of Medicine, charter class of 2015, in Rochester, Mich., from which she which chronicles her journey through medical training from day 1 of medical school.

Ira S. Nash, MD, FACP, is the senior vice president and executive director of the North Shore-LIJ Medical Group, and a professor of Cardiology and Population Health at Hofstra North Shore-LIJ School of Medicine. He is Board Certified in Internal Medicine and Cardiovascular Diseases and was in the private practice of cardiology before joining the full-time faculty of Massachusetts General Hospital.

Zackary Berger
Zackary Berger, MD, ACP Member, is a primary care doctor and general internist in the Division of General Internal Medicine at Johns Hopkins. His research interests include doctor-patient communication, bioethics, and systematic reviews.

Controversies in Hospital Infection Prevention
Run by three ACP Fellows, this blog ponders vexing issues in infection prevention and control, inside and outside the hospital. Daniel J Diekema, MD, FACP, practices infectious diseases, clinical microbiology, and hospital epidemiology in Iowa City, Iowa, splitting time between seeing patients with infectious diseases, diagnosing infections in the microbiology laboratory, and trying to prevent infections in the hospital. Michael B. Edmond, MD, FACP, is a hospital epidemiologist in Iowa City, IA, with a focus on understanding why infections occur in the hospital and ways to prevent these infections, and sees patients in the inpatient and outpatient settings. Eli N. Perencevich, MD, ACP Member, is an infectious disease physician and epidemiologist in Iowa City, Iowa, who studies methods to halt the spread of resistant bacteria in our hospitals (including novel ways to get everyone to wash their hands).

db's Medical Rants
Robert M. Centor, MD, FACP, contributes short essays contemplating medicine and the health care system.

Suneel Dhand, MD, ACP Member
Suneel Dhand, MD, ACP Member, is a practicing physician in Massachusetts. He has published numerous articles in clinical medicine, covering a wide range of specialty areas including; pulmonology, cardiology, endocrinology, hematology, and infectious disease. He has also authored chapters in the prestigious "5-Minute Clinical Consult" medical textbook. His other clinical interests include quality improvement, hospital safety, hospital utilization, and the use of technology in health care.

Juliet K. Mavromatis, MD, FACP, provides a conversation about health topics for patients and health professionals.

Dr. Mintz' Blog
Matthew Mintz, MD, FACP, has practiced internal medicine for more than a decade and is an Associate Professor of Medicine at an academic medical center on the East Coast. His time is split between teaching medical students and residents, and caring for patients.

Everything Health
Toni Brayer, MD, FACP, blogs about the rapid changes in science, medicine, health and healing in the 21st century.

Vineet Arora, MD, FACP, is Associate Program Director for the Internal Medicine Residency and Assistant Dean of Scholarship & Discovery at the Pritzker School of Medicine for the University of Chicago. Her education and research focus is on resident duty hours, patient handoffs, medical professionalism, and quality of hospital care. She is also an academic hospitalist.

Glass Hospital
John H. Schumann, MD, FACP, provides transparency on the workings of medical practice and the complexities of hospital care, illuminates the emotional and cognitive aspects of caregiving and decision-making from the perspective of an active primary care physician, and offers behind-the-scenes portraits of hospital sanctums and the people who inhabit them.

Gut Check
Ryan Madanick, MD, ACP Member, is a gastroenterologist at the University of North Carolina School of Medicine, and the Program Director for the GI & Hepatology Fellowship Program. He specializes in diseases of the esophagus, with a strong interest in the diagnosis and treatment of patients who have difficult-to-manage esophageal problems such as refractory GERD, heartburn, and chest pain.

I'm dok
Mike Aref, MD, PhD, FACP, is an academic hospitalist with an interest in basic and clinical science and education, with interests in noninvasive monitoring and diagnostic testing using novel bedside imaging modalities, diagnostic reasoning, medical informatics, new medical education modalities, pre-code/code management, palliative care, patient-physician communication, quality improvement, and quantitative biomedical imaging.

Informatics Professor
William Hersh, MD, FACP, Professor and Chair, Department of Medical Informatics & Clinical Epidemiology, Oregon Health & Science University, posts his thoughts on various topics related to biomedical and health informatics.

David Katz, MD
David L. Katz, MD, MPH, FACP, is an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care.

Just Oncology
Richard Just, MD, ACP Member, has 36 years in clinical practice of hematology and medical oncology. His blog is a joint publication with Gregg Masters, MPH.

Kevin Pho, MD, ACP Member, offers one of the Web's definitive sites for influential health commentary.

MD Whistleblower
Michael Kirsch, MD, FACP, addresses the joys and challenges of medical practice, including controversies in the doctor-patient relationship, medical ethics and measuring medical quality. When he's not writing, he's performing colonoscopies.

Medical Lessons
Elaine Schattner, MD, FACP, shares her ideas on education, ethics in medicine, health care news and culture. Her views on medicine are informed by her past experiences in caring for patients, as a researcher in cancer immunology, and as a patient who's had breast cancer.

Mired in MedEd
Alexander M. Djuricich, MD, FACP, is the Associate Dean for Continuing Medical Education (CME), and a Program Director in Medicine-Pediatrics at the Indiana University School of Medicine in Indianapolis, where he blogs about medical education.

More Musings
Rob Lamberts, MD, ACP Member, a med-peds and general practice internist, returns with "volume 2" of his personal musings about medicine, life, armadillos and Sasquatch at More Musings (of a Distractible Kind).

David M. Sack, MD, FACP, practices general gastroenterology at a small community hospital in Connecticut. His blog is a series of musings on medicine, medical care, the health care system and medical ethics, in no particular order.

Reflections of a Grady Doctor
Kimberly Manning, MD, FACP, reflects on the personal side of being a doctor in a community hospital in Atlanta.

The Blog of Paul Sufka
Paul Sufka, MD, ACP Member, is a board certified rheumatologist in St. Paul, Minn. He was a chief resident in internal medicine with the University of Minnesota and then completed his fellowship training in rheumatology in June 2011 at the University of Minnesota Department of Rheumatology. His interests include the use of technology in medicine.

Technology in (Medical) Education
Neil Mehta, MBBS, MS, FACP, is interested in use of technology in education, social media and networking, practice management and evidence-based medicine tools, personal information and knowledge management.

Peter A. Lipson, MD
Peter A. Lipson, MD, ACP Member, is a practicing internist and teaching physician in Southeast Michigan. The blog, which has been around in various forms since 2007, offers musings on the intersection of science, medicine, and culture.

Why is American Health Care So Expensive?
Janice Boughton, MD, FACP, practiced internal medicine for 20 years before adopting a career in hospital and primary care medicine as a locum tenens physician. She lives in Idaho when not traveling.

World's Best Site
Daniel Ginsberg, MD, FACP, is an internal medicine physician who has avidly applied computers to medicine since 1986, when he first wrote medically oriented computer programs. He is in practice in Tacoma, Washington.

Other blogs of note:

American Journal of Medicine
Also known as the Green Journal, the American Journal of Medicine publishes original clinical articles of interest to physicians in internal medicine and its subspecialities, both in academia and community-based practice.

Clinical Correlations
A collaborative medical blog started by Neil Shapiro, MD, ACP Member, associate program director at New York University Medical Center's internal medicine residency program. Faculty, residents and students contribute case studies, mystery quizzes, news, commentary and more.

Interact MD
Michael Benjamin, MD, ACP member, doesn't accept industry money so he can create an independent, clinician-reviewed space on the Internet for physicians to report and comment on the medical news of the day.

PLoS Blog
The Public Library of Science's open access materials include a blog.

White Coat Rants
One of the most popular anonymous blogs written by an emergency room physician.

Powered by Blogger

RSS feed