Our Latest Perspectives Posts

Preventing Infection with Environmental Controls: A “Broad-spectrum” Approach
Written by By the Water Quality & Health Council

Environmental ControlsAs reports of the dangers of antibiotic-resistant bacteria and “superbug” infections continue to make headlines, we think the time is right to consider the environmental controls at our disposal for fighting the spread of infectious illness. Environmental controls lower the risk of infection by taking the fight against pathogens into the environment. Once implemented, environmental controls can be thought of as offering “broad-spectrum” antibiotic protection.  

Examples of Environmental Controls in Preventing Infection

Disinfecting frequently touched surfaces: Hand contact with pathogens on frequently touched surfaces, such as door knobs and hand rails, is a common way to spread infection. Surfaces may look clean but looks can be deceiving, and the surface may be teeming with germs invisible to the naked eye.  Once hands are contaminated, the host has only to touch his or her face—especially the eyes, nose or mouth—to increase the likelihood of infection. Regularly disinfecting frequently touched surfaces with disinfectants, such as dilute chlorine bleach solutions, can go a long way toward lowering the risk of infection.  

Appropriate handwashing: Handwashing for at least 20 seconds with warm, soapy water can send most hand-clinging germs down the drain (see “The Right Way to Wash Your Hands”). When soap and water are unavailable, alcohol-based hand sanitizer (with at least 60 percent alcohol) is a good compromise. Attention to hand hygiene is particularly important before preparing food, eating, and after using the bathroom or changing diapers.  

The Centers for Disease Control and Prevention calls handwashing a “’do-it-yourself’ vaccine that is “…one of the best ways to remove germs, avoid getting sick, and prevent the spread of germs to others. It’s quick, it’s simple, and it can keep us all from getting sick. Handwashing is a win for everyone, except the germs.” In many situations, especially in public settings, handwashing is the most proactive measure an individual can take to avoid infection.  

Engineering solutions: We can also dodge pathogens with smart engineering solutions. Recently we wrote about a “staged mode of transmission” of superbug bacteria which, once washed down the drains of hospital sinks, colonize the P-shaped portion of the drainpipe and grow slowly back up toward the sink strainer. From there they are strategically positioned to be launched into the environment when running water impacts the strainer area. One way to avoid this exposure could be to relocate sink drains to an area of the sink not directly below the default faucet position.

Other engineering solutions that can help curtail the spread of germs are:

  • Antimicrobial copper alloy (such as brass or bronze) door knobs and countertops. 
  • Motion-activated faucets, soap dispensers and towel dispensers in public restrooms.
  • Disposable sanitizing wipes positioned at the entrances to grocery stores to wipe down shopping cart handles.

There is some speculation that the wonderful effectiveness of early antibiotics gave way to a relaxed attitude toward environmental controls. As the development of new antibiotics lags behind the evolution of resistant bacteria, it makes sense to harness all of the tools available to us, including time-tested, “broad-spectrum” environmental controls.  

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Superbugs: Rising from Hospital Drainpipes
Written by By Barbara M. Soule, RN, MPA, CIC, FSHEA, FAPIC

SuperbugsSuperbugs are sneaky creatures. A new University of Virginia (UVA) study reveals how these microbes, once washed down the drains of hospital sinks, colonize the drainpipe and rise up slowly along the sides of the pipe, eventually reaching the sink strainer. The researchers hypothesize that when the sink faucet is operated, the potential pathogens and superbugs may be splashed from the strainer over a distance of more than two feet, presenting an infection risk to vulnerable hospital patients.

A Significant Issue

Superbugs are multidrug resistant bacteria that are responsible for two million cases of illness and some 23,000 deaths per year, according to the Centers for Disease Control and Prevention (CDC) website. A CDC report notes that over 720,000 infections were contracted in hospitals in 2011 and that 75,000 of those patients died. The UVA researchers found over 32 recent reports describing the spread of bacteria resistant to the important antibiotic carbapenem via sinks and other reservoirs of water within hospitals. Most of the reports are associated with “outbreaks in the intensive care setting, affecting the critically ill and the immunocompromised,” according to a related study.

A “Staged Mode of Transmission”

The UVA team describes a “staged mode of transmission” to explain how hospital patients and staff may be exposed to superbugs. The microbes colonize the P-shaped traps, or “P traps,” of hospital sink drainpipes just below the bowl of the basin, where water pools. From there, nourished by various discarded liquids, such as intravenous fluids, feeding supplements and leftover beverages, they migrate back toward the sink at the rate of about one inch per day, moving as a growing biofilm. Biofilms are slimy mats of microorganisms that are difficult to wash away or destroy.

Based on the design of most sink plumbing, in approximately one week’s time the superbugs are present in the sink strainer area. From there, they are well-positioned to be dispersed around the sink and onto adjacent counters by water streaming from the flowing faucet. The frightening scenario culminates with the exposure of patients, who can least fight infection, to antimicrobial resistant superbugs.

Findings from the “Sink Lab”

To better study the stages of transmission of superbugs from hospital sink plumbing, the UVA research team constructed a unique “sink lab.” The lab features five identical sinks modeled after the intensive care unit (ICU) sinks in UVA’s Charlottesville hospital and connected in wastewater plumbing. A harmless form of E. coli was used as a surrogate pathogen. One significant finding from the “sinks in series” design is that the bacteria can spread through plumbing connections to neighboring sinks, demonstrating that the superbugs spread both upward and downward out of P traps.

Preventing Superbug Infections from Sink Drains

Does the design of the hospital sink and its plumbing require modification to help prevent this mode of exposure to superbugs? Is the P-shaped trap—originally designed to prevent the escape of sewer odors—an inadvertent public health risk? Ironically, the sink is often the first destination for people entering and the last stop for those leaving the ICU, as hand-washing is a well-known and strongly endorsed infection prevention control measure. Should hospital sinks be redesigned to prevent water from the faucet splashing into the drain area and casting superbugs into the ICU environment? Or can the P-shaped section of the drain be treated in a way that prevents colonization by bacteria?

Between 2011 and 2012 a superbug outbreak at the National Institutes of Health Clinical Center killed 11 patients. According to an interview with Dr. Tara Palmore, a hospital epidemiologist at the Center, bleach and scrubbing helped end the outbreak. The sink traps were removed and “scrubbed out with wire brushes and bleach,” followed by daily bleach spraying down the drains. Over time, the drug-resistant bacterial colonies were removed. Yet, Palmore notes that there are some very difficult cases in which nothing seems to work.

The UVA team is now working with the CDC to understand exactly how patients may be infected with superbugs emerging from drainpipes. This will help inform the solution to the insidious problem of deadly hospital-acquired superbug infections. We congratulate the researchers on their significant work to date and eagerly await further results of their important efforts.

Barbara M. Soule, RN, MPA, CIC, FSHEA, FAPIC is an Infection Preventionist and a member of the Water Quality & Health Council.

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The Secret Life of Bleach

Chlorine bleach – that household staple usually parked in the laundry – has additional uses besides “whitening your whites”. During cold and flu season, dilute bleach solutions can be used to wipe down frequently touched surfaces to help prevent the spread of viruses and other pathogens (disease-spreading germs) among family members.

Bleach solutions also destroy bacteria, including Salmonella and E. coli, common foodborne pathogens that may lurk on kitchen work surfaces. Used smartly, bleach solutions pack a powerful punch against germs that can make your family sick.

How Does Bleach Destroy Bacteria?

Several years ago, a University of Michigan research team led by Dr. Ursula Jakob, studying the effects of heat stress on bacteria, inadvertently discovered the mechanism by which bleach destroys bacteria. The short, entertaining video above, “The Secret Life of Bleach,” features creative animation that describes the mechanism of bacteria destruction.

As the video demonstrates, exposure to bleach causes proteins—which are complex, three-dimensional structures that control the life functions of bacteria—to permanently unfold, an effect that is analogous to a house collapsing. 

Bleach in Our Bodies

One of the fascinating points made in the video is that the human body produces and uses chlorine bleach internally as a natural disinfectant. White blood cells are “little bleach factories,” according to Dr. Jakob, that are activated to destroy bacteria detected inside the body, helping to fight disease. How interesting to think that the inventors of bleach probably never realized their own bodies were creating and using this substance naturally!

Thanks to Dr. Jakob and her team, we now know how bleach destroys bacteria both within us and around us. Bleach is giving up some of its age-old secrets…

Using Bleach for Household Chores*

Task Regular Strength (5.25%) Bleach in 1 Gallon of Water High Strength (8.25%) Bleach in 1 Gallon of water
Wall and floor disinfection following flooding ¾ cup ½ cup
Laundry disinfection and whitening (for a full load of laundry in a washing machine) ½ cup 1/3 cup
Disinfecting nonporous surfaces (e.g., vinyl, ceramic tile, porcelain) against norovirus (“the stomach bug”) 1 cup 3/4 cup
Disinfecting hard surfaces against flu transmission ¼ cup 2 ½ tablespoons
Disinfecting kitchen cloths 3 tablespoons 2 tablespoons
Routine disinfection of food-contact surfaces 1 tablespoon 2 teaspoons

*Table recommendations are partially based on Guidelines for Determining How Much Clorox® Concentrated to Use in Continuous Chlorination Disinfection Systems in place of Clorox® Regular and Clorox® Ultra bleach, Maine Center for Disease Control and Prevention

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A Fun Holiday Hand-washing Activity for Kids

As our families and friends gather to celebrate the holidays, we look forward to enjoying good company, delicious food and exchanging gifts. One aspect of the holidays we don’t enjoy, however, is exchanging the germ du jour.

Many adults are aware that frequent hand-washing—and hand sanitizer use in a pinch–can help avoid the “re-gifted” germs that cause colds, flu, the stomach bug (norovirus) and more. The Centers for Disease Control and Prevention tell us that hand-washing is one of the most important steps we can take to avoid getting sick and spreading germs to others, so how can we help the children in our lives practice proper hand hygiene?

The American Cleaning Institute offers a fun resource for children to “Create a colorful holiday!” with its “Clean Your Paws for Santa Claus Coloring Page.” The image caption clarifies that handwashing “with soap and warm water for 20 seconds” precedes the reward of reaching for a cookie. Why not print out a few copies and share them with the children at your holiday gathering?

Here’s wishing you Happy, Healthy Holidays!

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Handkerchief or Tissues? That is the Question!

Whether you use a handkerchief or tissues when you are sick, leaving them out on a common surface only helps spread your germs.

Whether you use a handkerchief or tissues when you are sick, leaving them out on a common surface only helps spread your germs.

Ah-choo! How do you handle sneezes and a runny nose? Do you reach for a handkerchief or tissues? Which option is more sanitary? Which option is most environmentally responsible? How do affordability, comfort and convenience factor into your decision? More men than women may prefer handkerchiefs, but that may be changing. Rather than endorse one option over another, we provide the following analysis for your consideration.



Comparing Handkerchiefs and Tissues

Handkerchief Tissues
How Sanitary? Handkerchiefs are adequately sanitary if stored away immediately after use (e.g., in a pocket or purse), followed by the user washing his or her hands. (Exposure risk remains for the person laundering handkerchiefs.) Tissues are adequately sanitary if disposed of immediately after use, followed by the user washing his or her hands. (Exposure risk remains for the person removing trash.)
How Environmentally Responsible? Laundered handkerchiefs can be reused many times. Laundering and ironing require energy, water, detergent and sanitizer (see directions below for sanitizing with bleach). Tissues are manufactured from a renewable resource using energy, water and chemicals. Used tissues can be composted, or they enter the general waste stream.
How Comfortable and Convenient? Handkerchiefs can be purchased to please the user’s preferences in fabric and size. They can be laundered to enhance softness (e.g., with fabric softener). Portable tissue packets are available as well as a range of tissue box shapes and sizes. Tissues pre-moistened with aloe and other products are also available to help soothe irritated skin.


How to Launder Cotton or Poly/cotton Handkerchiefs

According to the Clorox website, soak chlorine-bleachable laundry in ¼ cup regular bleach per gallon of water or 3 tablespoons of concentrated bleach per gallon of water for up to 5 minutes. Rinse. Follow-up with a hot water machine wash using detergent and bleach.

Our advice is to choose the option you prefer based on the factors that mean the most to you. Whichever choice you make, help reduce the likelihood of spreading germs by staying mindful that germs go wherever nasal mucous goes. For example, blowing your nose and leaving the handkerchief or tissues in the open may infect others in your living or work space. Not washing your hands (or at least using a hand sanitizer) after blowing your nose is another way to spread your illness to others through commonly touched surfaces. What is the “life cycle” of the item used to wipe your nose? How can you minimize the risk of spreading germs through that item? It’s not rocket science, but it is worth some thought.


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What Cooking Shows Don’t Teach

Want to know how to prepare a delicious recipe? Tune in to a TV cooking show. Just don’t expect to view some of the most important cooking steps! According to a new study1 in the Journal of Nutrition Education and Behavior (abstract), today’s cooking shows are missing “an opportunity to model and teach good food safety practices for millions of viewers.” In fact, the researchers found in 39 episodes from 10 television cooking shows, the majority of episodes failed to demonstrate:

  • Proper use of utensils and gloves
  • Protection from contamination
  • Maintaining time and temperature rules

Foodborne Illness: Learn from “Maria”

How to Sanitize Kitchen Surfaces with Chlorine Bleach Solution

  1. Clean: Wash hard surfaces with hot, soapy water, then rinse with clear water.
  2. Sanitize: Apply a solution made by adding ½ tablespoon of chlorine bleach2 to ½ gallon of water. Air dry.
Bleach solutions break down over time, turning into salty water, so prepare bleach solutions daily. Never mix ammonia-containing cleaners with bleach.

Each year there are 48 million cases of foodborne illness in the US, including 128,000 hospitalizations and 3,000 deaths. Foodborne illnesses, most of which are infections caused by bacteria, viruses and parasites, can even have long-term health consequences, according to the Centers for Disease Control and Prevention (CDC). To highlight some of the most common food safety mistakes, CDC developed a series of short cooking show style videos called “Recipes for Disaster.” Viewers are invited to learn the right steps in food preparation as the fictional cook “Maria” does everything wrong. In “Contaminated Carbo Load,” for example, Maria chops vegetables on an unwashed and unsanitized cutting board that previously held raw chicken and bacon. In “Bacteria BBQ,” Maria leaves steaks marinating on the counter overnight, “just as her Nanna did.” Maria’s family and friends enjoy her cooking but hours later suffer the consequences of her cooking mistakes.

Missed Opportunities

The new study by Cohen and Olson cites a recent Harris Poll that finds “50% of consumers reported watching many of the hundreds of television cooking shows very often or occasionally.” Unfortunately, the researchers found that the percentage of shows in conformance with recommended food safety practices was much lower than that observed in restaurant employees and consumers. For example, as the authors note, fruits and vegetables are the leading sources of foodborne illness in the US, yet less than 10% of the food shows they viewed demonstrated handling produce properly. Additionally, in only 13% of episodes were food safety practices even mentioned.

Recommendations of the study authors include:

  • Food safety training for chefs and food show contestants
  • Modifying TV kitchen sets to support food safety actions, such as incorporating sinks to use for hand-washing and featuring different colored cutting boards for separate use when handling raw meats and vegetables
  • Adding food safety as a criterion in TV cooking competitions
  • Discussing food safety in cooking show scripts, such as demonstrating the proper use of food thermometers and when to change gloves or wash hands

TV cooking shows have a wonderful but underutilized opportunity to demonstrate more than the latest and greatest ways to stuff zucchini or roast a chicken. Modeling good food safety practices for millions of viewers could go a long way toward reducing foodborne illness.


Barbara M. Soule, R.N. MPA, CIC, FSHEA, FAPIC is an Infection Preventionist and a member of the Water Quality & Health Council.

Click here to download this article.

1 Cohen, N.L. and Olson, R.B. (2016). “Compliance with Recommended Food Safety Practices in Television Cooking Shows,” Journal of Nutrition Education and Behavior, Vol. 48, pp. 730-735.

2 Directions are for 5.25% bleach. Decrease amount of bleach to 1 teaspoon per half-gallon if using 8.25% bleach.



The Black Friday Shoppers’ Health and Safety Survival Guide

Determined to brave the traffic, crowds and general madness of Black Friday, many shoppers strike out to take advantage of deep discounts on holiday goods. We offer tips to help ensure shoppers return home from these shopping adventures safely and in good health.

Safety First

  • As exciting as it is to get to the sales early, don’t compromise safety when driving or walking to the shops. Obey traffic and pedestrian rules—arrive alive and unharmed. Exercise extra caution driving and walking in packed parking lots.
  • Reduce your chances of being caught and injured in a stampede at “door buster” sales. It’s better to hang back or off to the side than to risk injury in a rushing crowd.

Be a Healthy Shopper

  • Be mindful that frequently touched surfaces such as door handles and electronic key pads are drop off and pick-up points for germs. Keep your hands away from your face while shopping, and make frequent use of portable hand sanitizer.
  • Use your knuckle instead of the pad of your finger to depress elevator keys or automatic door openers.
  • Using a public restroom? Use a clean tissue or paper towel to act as a barrier between you and the restroom door handle as you enter and exit. Wash your hands thoroughly after using the restroom.
  • Cough and sneeze into a tissue or into the crook of your elbow to prevent germs spreading to your fellow shoppers.
  • Did you remember to get a flu shot? The flu vaccine is recommended for all people over the age of six months, with rare exception. It’s not too late to get one now, but next year remember, “Vaccine by Halloween” for the timeliest protection against the seasonal flu. See your doctor if you have questions about the flu vaccine.
  • Stay home on Black Friday if you are sick. Considering how many people you could potentially infect in mobbed shopping centers, online bargain shopping just might be the kinder, gentler option when you are under the weather. And remember: Cyber Monday is only three days after Black Friday.
  • Recognizing that some of the best sales begin very early in the day, consider putting your egg nog down on Thanksgiving night and getting a good night’s sleep.

Happy Bargain Hunting!

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Holiday Food Safety and the Foodkeeper App

A beautifully arranged holiday dinner table is a feast for the senses. Occasionally, however, festive fare that looks perfectly delectable can sicken unsuspecting diners. There are many ways in which the “perfect” holiday dinner can go horribly wrong. Fortunately, most foodborne illness can be avoided when cooks maintain and apply a keen awareness of the basics of food safety. Add to that a new “app” issued by the US Department of Agriculture (USDA), and safe food storage and preparation can be a snap this holiday season.

Food Safety Basics

“Clean” starts with the cooks washing their hands with soap and warm water before and after handling any food item (not just raw animal or vegetable products). Food preparation surfaces, such as cutting boards and countertops, should be thoroughly washed with soap and hot water, followed by sanitizing with a solution of one tablespoon of unscented, liquid chlorine bleach per gallon of water. Air-dry.

“Separate” foods so that juices from raw meats, poultry and seafood, which can contain harmful bacteria, do not contact ready-to-eat food. Place raw meats, poultry and seafood in plastic bags in the refrigerator to prevent their juices from dripping onto other food. To lower the risk of accidental dripping, place those plastic bags on the lowest shelves of the refrigerator.

Designate one cutting board for raw fruits and vegetables and another for raw meats, poultry and seafood.

Never place cooked food back on the same plate that previously held raw food unless the plate has first been washed in hot, soapy water.

“Cook” foods to safe minimum internal temperatures to destroy harmful bacteria. The food thermometer should be placed in the thickest part of the food, away from bone, fat or gristle. According to the Foodsafety.gov website, poultry, including chicken, turkey, duck and goose, should be cooked to a minimum internal temperature of 165 degrees F.

“Chill” foods that should be refrigerated at 40 degrees F or below. Defrost frozen foods in the refrigerator, microwave or cold water. Do not leave food at room temperature for more than 2 hours (or 1 hour when the air temperature is 90 degrees F or more). Meat defrosted in the refrigerator is safe to re-freeze before or after cooking. Foods defrosted in the microwave or cold water must be cooked before freezing. Store eggs in the refrigerator in their original carton and use within three to five weeks.

An App for the Kitchen

The new “Foodkeeper” app, developed by the USDA’s Food Safety and Inspection Service, with Cornell University and the Food Marketing Institute, was designed to help consumers understand and optimize food and beverage storage. The app is available for Android and Apple devices.

Here is a sampling of the type of information available through the Foodkeeper app:

  • Cooked poultry dishes (e.g., turkey and chicken) last 3 to 4 days when stored in the refrigerator and 4 to 6 months if stored frozen. Poultry should be cooked in an oven to a safe minimum temperature of 165 degrees F.
  • Fresh potatoes last 1 to 2 months in the pantry (the recommended storage method for whole potatoes) and 1 to 2 weeks in the refrigerator (refrigerating potatoes is not recommended as potatoes may darken during cooking and develop an unpleasantly sweet taste1 )
  • Bagged greens, such as spinach and lettuce, last 3 to 5 days after the date on the bag when stored in the refrigerator, and 2 days if refrigerated after opening. Freezing bagged greens is not recommended.
  • Hard cheeses such as cheddar, Swiss and block parmesan last 6 months in the refrigerator before opening, and 3 to 4 weeks in the refrigerator after opening, but 6 months if stored frozen.
  • Ready to Bake Pie Crust should be used by the date indicated on the package when stored in the refrigerator, but can last up to 2 months if stored in the freezer.
  • Whipped, sweetened cream lasts 1 day when stored in the refrigerator and 1 to 2 months if stored frozen.
  • Fruit juice and punch in cartons last 3 weeks in the pantry, 7 to 12 days in the pantry if stored after opening, and 8 to 12 days if refrigerated after opening.

Keep the four food safety basics in mind as you gear up for holiday cooking. And remember the Foodkeeper app, which can help you decide on the usability of ingredients. Finally, trust your instincts: If a food or drink looks suspect, follow the old adage, “When in doubt, throw it out.”

Here’s wishing you a happy and safe Holiday Season!

Linda F. Golodner is President Emeritus of the National Consumers League and Vice Chair of the Water Quality and Health Council.

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1 The recommendation not to refrigerate potatoes comes from the United States Potato Board.



Five Tips for Getting through Flu Season

The 2016–2017 flu season is off to a slow start, but the Centers for Disease Control and Prevention (CDC) predicts an uptick in flu activity in the coming weeks and months. Here are some tips to help prepare and inform you as flu appears in your community:
Flu Season Ahead

  1. Get a Flu Shot: CDC recommends a flu shot for everyone six months old and older. Flu vaccines protect against the three or four flu viruses most likely to spread in a given season. What segments of the population are most vulnerable to flu-related complications? The very young, people aged 65 and older, pregnant women, and people with chronic health conditions such as asthma, diabetes or heart and lung disease are most at risk for complications.

To help avoid spreading the flu to those in their care, health care workers and people who care for vulnerable populations, including families of babies under the age of six months, should be sure to get their flu shot.

Maximum immune system protection against the flu takes about two weeks from the time of vaccination. CDC advises people to get their flu shots each year by the end of October. Some health departments are proclaiming: “Vaccine before Halloween!”1 This year’s breaking news on flu is that the nasal spray is not recommended by CDC because its effectiveness is in question.

  1. Wash Your Hands: Washing your hands frequently and thoroughly is one of the most important ways to elude the flu. Flu virus particles are very good at hitching a ride from contaminated surfaces (door knobs and hand rails, for example)—where they gather like airline passengers at a departure gate—to your hands and then for the “flight” to your eyes, nose and mouth. Viruses can only spread by infecting new hosts, and they appreciate not being washed down the drain. Give them the slip with thorough hand washing (use alcohol-based hand rub if soap and water are unavailable), and keep your hands away from your face.
  1. Disinfect Frequently Touched Surfaces: Destroy flu virus particles where they lurk to lower your odds of picking them up and becoming infected. Clean surfaces first with detergent and water and then sanitize using two teaspoons of high strength household bleach (8.25%) per gallon of water. Alternatively, wipe down surfaces with disposable pre-moistened wipes containing chlorine bleach.
  1. Maintain a Healthy Lifestyle: Get adequate sleep, maintain a healthy diet, stay hydrated and exercise regularly to keep your immune system on alert against flu and other infections.
  1. Be Kind to Others: If you do get the flu, stay home and limit your contact with others. Cover your coughs and sneezes with a disposable tissue and wash your hands after using tissues. Tissues not available? Cough or sneeze into your elbow to help prevent projecting thousands of infected mucous droplets into the air that others breathe! Finally, keep your distance from those who appear to have flu symptoms but have opted to be out and about anyway.

Not sure if you have the flu or a cold? Use this chart to help you decide. For more information on the seasonal flu, please see this CDC website.

Ralph Morris, MD, MPH, is a Physician and Preventive Medicine and Public Health official living in Bemidji, MN.

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1 See, for example, this WJHG.com video.



Norovirus and Chlorine Bleach: The Perfect Pathogen Meets its Match

Colorized transmission electron micrograph of norovirus particles

Colorized transmission electron micrograph of norovirus particles

Courtesy of CDC/ Charles D. Humphrey


Is there such a thing as a “perfect” human pathogen? If by perfect we mean a disease-causing microorganism that is highly contagious; quickly and profusely shed in the environment by its hosts; and able to evolve rapidly to both avoid widespread human immunity and ensure a large pool of susceptible hosts, then norovirus comes very close. Norovirus expert Dr. Aron Hall of the Centers for Disease Control and Prevention’s (CDC’s) Division of Viral Diseases cleverly entertained the notion that noroviruses could be the perfect human pathogens in a 2012 editorial commentary.1

Notorious Norovirus

Sometimes referred to as “the stomach bug,” and infamous for spreading through cruise ships, norovirus is responsible for some 19-21 million cases of gastrointestinal illness in the US annually.2 The very young, the very old and the immunocompromised are especially vulnerable to norovirus. It is the most common cause of foodborne illness in the US—responsible for at least 50,000 hospitalizations and between 570 and 800 deaths annually.3 But norovirus respects no borders. It is a global player. Found in both developed and developing countries, it is the main cause of half of all gastroenteritis outbreaks worldwide. A 2016 analysis4 estimated the virus’ global economic burden at $60 billion, the largest share of which ($56 billion) is lost productivity.

Means of Transmission

Norovirus is spread in three main ways: (1) close personal contact with an infected individual; (2) ingesting contaminated food or water; and (3) contact with contaminated surfaces. Norovirus can be transmitted by ingesting food contaminated at the source (e.g., fruits and vegetables) or by infected food handlers. (Food handlers who return to work sooner than 48 hours after they no longer have symptoms can still spread norovirus.5 ) Norovirus has remarkable staying power on environmental surfaces where it can persist for up to two weeks. It can survive freezing and withstand heating to 140 degrees. To destroy norovirus in drinking water, CDC recommends6 bringing water to a rolling boil (212 degrees Fahrenheit) for one minute. Astonishingly, only 18 norovirus particles are required to infect a human host. For perspective, there are billions of particles in the stool and vomit of infected individuals.

Outsmarting Norovirus

Efforts to develop a vaccine for norovirus are still in their infancy,7 so proper hygiene and surface disinfection practices must be employed to control the spread of the perfect pathogen. People infected with norovirus are advised to limit their contact with others for at least two days after symptoms have ended. Disinfecting surfaces contaminated with the persistent norovirus can go a long way to curtailing outbreaks. Properly prepared chlorine bleach solutions (see below) destroy norovirus on surfaces. Simply cleaning surfaces with soap and water or other cleaning product can actually spread virus particles. In the City of Albuquerque, for example, restaurant staff are encouraged to switch from quaternary ammonium disinfectants to chlorine bleach disinfectants when a norovirus outbreak occurs.8

Communicating a Disinfection Strategy

In 2012, the Water Quality and Health Council participated in a partnership with public health experts, including the New Jersey Somerset County Department of Health, the CDC, the National Environmental Health Association and others, to develop a series of downloadable posters featuring directions for preparing bleach solutions to destroy noroviruses on surfaces. For example, the posters include detailed directions on how to clean and disinfect an area affected by a vomiting or diarrhea incident. Posters are available in English, Spanish and French and can be found at http://www.disinfect-for-health.org/tools-reduce-spread-norovirus.

So when it comes to combatting the nearly perfect pathogen norovirus, remember:

  • the right way to wash your hands;
  • do not prepare food or care for others when you are sick;
  • wash fruits and vegetables and cook seafood thoroughly;
  • clean and disinfect contaminated surfaces using chlorine bleach or other disinfectant registered as effective against norovirus by the EPA; and
  • launder clothes thoroughly.

Linda F. Golodner is President Emeritus of the National Consumers League and Vice Chair of the Water Quality and Health Council.

Click here to download this article.

1 Hall, A.J. (2012). Noroviruses: The Perfect Human Pathogens? Journal of Infectious Diseases, 205: 1622-1624. http://jid.oxfordjournals.org/content/205/11/1622.full.

2 CDC (2015). Norovirus: U.S. Trends and Outbreaks, http://www.cdc.gov/norovirus/trends-outbreaks.html.

3 CDC (2015). Prevent the Spread of Norovirus, http://www.cdc.gov/features/norovirus/.

4 Bartsch, S.M., Lopman, B.A., Ozawa, S., Hall, A.J., and Lee, B.Y. (2016). Global Economic Burden of Norovirus Gastroenteritis, PLOS ONE, DOI:10.1371/journal.pone.0151219. http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0151219.

5 CDC (2014). Norovirus and Working with Food, http://www.cdc.gov/norovirus/food-handlers/work-with-food.html.

6 CDC (2015). Noroviruses and Drinking Water from Private Wells, http://www.cdc.gov/healthywater/drinking/private/wells/disease/norovirus.html.

7 CDC (205). Making a Norovirus Vaccine a Reality, https://blogs.cdc.gov/publichealthmatters/2015/03/making-a-norovirus-vaccine-a-reality/.

8 “Norovirus Kitchen/Dining Room Response Procedures, City of Albuquerque Environmental Health Department handout at 4th Annual Norovirus Conference, August 4, 2016.



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