infection control

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A sanitation perspective

HumanAvian InfluenzaHumanAvian Influenza

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CYNTHIA GOLDSMITH / CDC

By NICOLE KENNY, Manager of Professional & Technical Services, Virox Technologies Inc.

MMany people, certainly the international media, are look-ing at what is now primarily a viral infection of birds, andpredicting a doomsday scenario sufficient in scope to re-move almost half of humanity from the face of the earth.In the worst case hypothesis, our hospitals will quickly swell

beyond a rapidly diminishing capacity, workplaces will be abandonedgrinding commerce to a halt, any large public gathering will be dis-bursed by public order, transit systems will shut down, face maskswill be haute couture, and instead of shaking hands in casual greet-ing we will bump elbows. The good news is that this doomsdayscenario is about as likely as the Chicago Cubs winning the WorldSeries. The bad news is we need to get busy working on a plan for“the just-in-case.”

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HUMAN AVIAN INFLUENZAContinued From Page 29

Influenza ABC’sInfluenza is caused by a virus (although bacterial pneumonia

is a classic secondary impact of this viral infection and the causeof many deaths). Unlike bacteria that are complete cells and thatcan replicate on their own, viruses have to infect a host cell anduse the resources of that cell to reproduce. Viruses are the onlyorganisms in the world to have only one type of genetic materialand are thus broken down into either RNA viruses (ribonucleicacid) or DNA viruses (deoxyribonucleic acid). Influenza is a RNAvirus. There are three further divisions of influenza viruses: A,B and C. Influenza C rarely causes illness so we’ll forget aboutthat. Influenza B viruses are common, but only among humans,and they generally don’t make us as sick as Influenza A. Influ-enza A is the monster in the closet.

Influenza A viruses are found in a wide variety of terrestrialbeasts, winged creatures and ocean-dwelling behemoths – ducks,chickens, wild birds, pigs, horses, whales and many other ani-mals, including the human animal. It is further divided into sub-types according to the arrangement of two bumpy proteins onthe surface of the virus – hemagglutinin (H) and neuraminidase(N). There are 16 different hemagglutinin sub-types and nine

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different neuraminidase sub-types (144 possible combinations),all of which have been found among Influenza A viruses in birds.The current strain of influenza that is causing so much concernis a strain very fatal to birds, and has caused a few scattereddeaths among humans as well. It is called H5N1.

Genetics… What Ya Gonna DoThere’s a famous story of a meeting between Marilyn Munroe

and Albert Einstein. Munroe: “Imagine if we had children together…they’d have my looks and your brains. They’d be beautiful and brilliant.”Einstein replies, “Ah, but on the other hand, they might very well get mylooks and your brains, and then where would they be?” With genetics,you just can’t tell what you’re going to end up with. The sameholds true for viruses. An influenza virus that is devastating tobirds has a huge barrier (the species barrier) to overcome beforeit can infect humans as well. However, if that virus was com-mingled with other influenza virus strains, or if the virus were toinfect pigs (a short cut to human infectivity), it could eventuallybecome a danger to humans as well. It could happen… eventu-ally… certainly not quickly… maybe not at all.

Could It Happen?Almost invariably, when commentators speak of the poten-

tial influenza pandemic, they make reference to the 1918 “Span-ish Flu” that killed more than 50 million people worldwide at a

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time when the world’s population was a fraction of what it istoday. More people died in a single year of that outbreak than infive years of the Bubonic Plague. The Spanish Flu (although ithad little to do with Spain) killed only two to three per cent ofthe people who were infected. Compare that with the almost 70per cent death rate of humans who have become infected withthe H5N1 avian flu. Looks bad, right?

In fact, in 1918 the germ theory wasn’t entirely accepted yet,and doctors didn’t know about viruses and how to treat them.They certainly didn’t have antiviral medications, vaccinations, theWorld Health Organization, the CDC or the Public HealthAgency of Canada. There weren’t epidemiologist zealots scour-ing foreign lands looking for pockets of infectious disease, orpublic health officials ready to slaughter millions of birds at amoments notice. That flu pan-demic coincided with anothervery deadly pandemic – war.Soldiers crammed into barracksand troop ships, and huddled inthe cold, damp trenches ofWorld War One provided anideal field of transmission forthe virus – more people diedfrom influenza infection duringWorld War One than from bul-lets, bombs and bayonets. Today,soldiers are looked after withmeticulous care and wars aremuch more sanitary (sanitizedeven?). Modern healthcare, travel restrictions, health screeningand infection control precautions would make a global pandemicMUCH more difficult for an influenza virus to manage.

It HappensIn reality, influenza happens! Every year, tens of thousands

of North Americans suffer from an influenza infection. Thou-sands of those infected with influenza will die as a direct (severeinfluenza infection) or indirect (underlying illness) result. Withall of our focus on and fretting about a bird flu pandemic, wecan’t lose sight of the threat that is in our hospitals, nursing homes,schools and workplaces right now.

The best way to prevent a bird flu pandemic is to stop itbefore it starts – kill infected birds and stop dangerous practices.

Dangerous Practices: In Vietnam, a favourite sport among villagers iscock-fighting. To motivate a laidback rooster, the owner of the bird will holdits beak in his mouth. Apparently the acidity of the saliva really annoysthem. Perhaps this is an example why Vietnam has experienced the highestincidence of avian influenza in humans.Vaccination is another pre-ferred prevention strategy, but despite the billions of dollarscommitted to a vaccine, it is likely still years away. Thankfully,there is already an annual vaccination available for our usualstrains of influenza, and it helps to protect those who are at thegreatest risk. Planning, personal protective equipment and in-fection control practices are where the rubber really hits the road

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An influenza virusthat is devastatingto birds has a huge

barrier (the speciesbarrier) to overcome

before it can infecthumans as well.

in our workplaces and communities.

Influenza Prevention in Workplaces & Public Spaces“Planning Prevents Panic and Produces Profit” – Allen Soden’s

(President, Deb SBS-USA) often quoted “5-P’s” make good senseat any time, but particularly during influenza season or during atime of pandemic influenza hysteria. Companies that haveplanned ahead may find themselves working in health while theircompetitors languish in disease. Policies could (should) includesending ill people home and enabling staff to work in more iso-lated settings such as from home if possible. All internal spacesshould be well ventilated, preferably with fresh air. Dilution ofrespiratory secretions with fresh, flowing air is absolutely key. (Inote that my office doesn’t have windows that open).

Hand Hygiene, AgainHand washing is still the single most important measure to

reduce the risk of transmitting infectious organisms from oneperson to another. Influenza vi-ruses, thought to be exclusivelytransmitted by droplets spewedby coughing, sneezing, wheezinginfected people, are now knownto be as commonly transmittedhand-to-hand-to-face, or surface-to-hand-to-face. Our hands comeinto contact with contaminatedsurfaces and other people’s dis-gusting hands, and then directlyor indirectly contact the vulner-able mucous membranes in ourmouth, nose and eyes in a vari-ety of ways, and many times a

day. When we eat, or smoke, apply make-up, rub our eyes, wipe(or pick) our nose, and when we cross our arms and put a fingerto our mouth to look introspective and intelligent, we run therisk of infecting ourselves, possibly with a lethal strain of influ-enza. Regular hand washing with soap and water, and/or regularuse of an alcohol hand rub are necessary all the time. During fluseason, particularly if we are around sick people, it becomes es-sential. Remember though, if hands look, feel or smell soiled,they have to be washed rather than rubbed with alcohol.

Personal Protective EquipmentIn a healthcare environment it is appropriate for workers to

use several types of personal protective equipment (PPE) to pro-tect themselves and their patients – mask, gloves, gowns, etc. Itis particularly useful for those doing the viral spewing to covertheir mouth and nose with a mask. However, in the world out-side of our hospitals, presenting one’s self in public in such garbmight be somewhat socially isolating. And, unless a Plexiglas shieldcan be installed between the infected masses and those who workon the front lines of society (taxi and bus drivers, cashiers, waitstaff, etc.), during a large influenza outbreak or pandemic it mightbe necessary for the healthy workers to wear a surgical-style maskto protect themselves. When Hong Kong had a nasty flu out-break a few years ago the social stigma of wearing a mask in

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Policies could(should) includesending ill peoplehome and enablingstaff to work in moreisolated settingssuch as from home ifpossible.

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infection controlContinued From Page 33

public kept many people from doing sowhen they were ill despite a legal man-date to do so. When the governmentchanged the mandate such that everyonewho went into public places must wear amask, sick or not, the stigma was re-moved… everyone complied… the out-break was halted.

Surface SanitationDuring an influenza outbreak or pan-

demic, thorough cleaning of touchable

surfaces become hyper-important. Viruseswill live on environmental surfaces forlong enough that they can be picked upby passers-by and subsequently infect agreat many people. The influenza virus isan enveloped virus, meaning that it is eas-ily killed. Proper cleaning techniques withdetergent or a non-residual disinfectantwill effectively make the surface safe.Proper technique for cleaning high-touchsurfaces would include diluted detergentor disinfectant in a pail with several dis-

posable wipers or launderable cloths. Asa wiper or cloth is used on a surface it is notreturned to the bucket, but rather disposedof or set aside, thereby eliminating the riskof cross contamination of other cleancloths and surfaces. Disposable, pre-mois-tened pop-up wipers are also very useful. Aspray bottle and wiper is less than optimalbecause of the tendency to use the one clothon several surfaces thereby ensuring that acluster of influenza viruses in a wad of spu-tum gets smeared evenly over a much largersurface.

What Does It All Mean?On a note of closure, let me say that

the hype about bird flu is more immedi-ately dangerous to society than the virusitself. While it is true that someday we willlikely face an influenza pandemic of somesort, it is by no means certain that it willbe this particular virus, nor is it certainthat it will be any time soon. However,the fear generated by all of the media re-ports will certainly cause a society-wideincrease in anxiety, leading to increasedblood pressure, heart disease, decreasedimmune response and depression. We canonly do what we can do. If we wash/dis-infect our hands faithfully, clean every-thing meticulously, employ proper PPE,and avoid snuggling up to people who arecoughing, sneezing and wheezing, the riskis very low indeed.

Nicole Kenny is the manager of Profes-sional and Technical Services at ViroxTechnologies Inc. – Tel: (905) 813-0110ext. 118, e-mail: nkenny@virox.com.Kenny graduated from the University ofGuelph with an Honours of BiologicalScience degree in 1994 and also holds anAssociate Chemist designation from theAssociation of Chartered Chemists ofOntario. In March 2003, during the firstwave of SARS, Kenny joined Virox Tech-nologies Inc., a company with a patentedtechnology in cleaning, disinfection andsterilization. As the manager of Profes-sional and Technical Services, Kenny isresponsible for Infection Control Educa-tion and Technical Support. In this capac-ity, incorporating her educational back-ground in Biomedical Science and Epi-demiology, Kenny has educated hundredsof people in many industries includingHealthcare, Public Health, AnimalHealth, Dental, Laboratory, Pharmaceu-tical and Food Processing.