This site is part of the Global Exhibitions Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 3099067.

Informa

Viruses: Simply Amazing

Article

By Milt Hinsch, MS, MBAC

Imagine a submicroscopic packet of proteins arranged symmetrically to enclose an inner genome -- and you have a virus. Viruses are so miniscule in size that most require electron microscopy to see them clearly, and more than 3,000 polio virus particles could fit end-to-end in a straight line across the period at the end of this sentence.  Now, that’s small! Yet, many viruses wreak havoc on vastly larger and more complex organisms.

Viruses’ accomplishments are amazingly made without benefits of legs, arms, wings or fins; without organs such as brains or neurological systems; and without an independent means of reproduction. To replicate, viruses typically must travel to a specific host, connect to a specific site on an appropriate host cell, and then inject their genomes, forcing the cell to construct copies of the invading virus.

As if that is not impressive enough, in human hosts, viruses force the host to manifest symptoms that provide the means to facilitate their spread (shedding) to other humans.  For example, cold and influenza viruses cause sneezing, runny nose, and other bodily excretions that are loaded with virus replicates seeking dispersal into the environment, awaiting a new host.  How do those viruses even know to create host symptoms that eventually promote their spread and ultimate survival? Pretty amazing!

Viruses usually specialize by hosts -- animals, humans, plants or microbes. Human viruses are subcategorized by various "-tropics" -- neurotropic (rabies), hepatotropic (hepatitis), enterotropic (polio), pneumotropic (influenza), etc., while others are pantropic (Marburg or Ebola).

Herpes simplex viruses are a good example of the ingenious nature of these bits of protein. Herpes simplex viruses are neurotropic viruses that find specific areas of the human body where the immune system is least likely to attack them – within the neurons of the sacral or trigeminal ganglia (fifth cranial nerves that supply the front part of the head, dividing into three facial areas -- ophthalmic, maxillary and mandibular) – where they can safely remain latent. How do Herpes simplex viruses know exactly where they are, where to go and how to get there? They don’t even have a map, much less a GPS on a cell phone.

In addition, other viruses cause their infected host cells to produce proteins to block key receptors used by antiviral cytokines designed to ‘alert’ the immune system to the presence of the viral invaders.  How do these submicroscopic packets of protein know what to tell host cells to do?

In short, viruses are miniscule, complex and amazing. They are also ubiquitous.

It has been said that humans walk around in a "viral cloud." The phrase “I feel like I’m walking around in a cloud” might be more true than we imagine. There are so many viruses in and around us, that perhaps we should call this article virUSes?

Most humans are infected with at least several latent viruses. Only when symptoms appear such as fever blisters (cold sores), shingles, etc., is it apparent that we are carrying latent viruses. 

Viruses must find their hosts to survive because viruses are ‘obligate intracellular parasites’. That means that, unlike other organisms, viruses require a host for replication. Viruses cannot replicate without a cellular host. The sheer number of viruses is most likely the way that viruses find their hosts.

Viruses must ‘find’ a host without the aid of GPS, smell, sight, taste, sound or touch. Many viruses seem to survive by ‘bumping into’ a host needed for replication. It seems that ‘blind luck’ plays a role based upon the statistical odds that if enough viruses contaminate the air, water, body fluids or surfaces after being shed from their hosts, some will contact other hosts, enter the appropriate cells and repeat the cycle. 

Bacteriophages (viruses that require bacteria as host cells) are an example that perhaps sheer numbers enable viruses to survive. The number of bacteriophage virus particles in the world’s waters total an estimated 1030, or 1,000,000,000,000,000,000,000,000,000,000!  If those 1030 phages were lined up end-to-end, they would reach 108, or 100 million light years!!
 
And those numbers represent only bacteriophage viruses – which does not include the other 320,000 estimated, known and unknown mammalian virus types! 
Of the known mammalian viruses, approximately 130 are pathogenic human viruses that comprise 21 families of RNA or DNA viruses known to cause human disease. 

While most published infection prevention articles discuss pathogenic bacteria – MRSA, VRSA, Clostridium difficile, Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, etc., it seems possible that there are many pathogenic viruses in and on each of us as well. So, with the ubiquitous nature of viruses, why does it seem that there is more written about bacteria than about viruses?

In numbers, viruses dominate Earth, as demonstrated by the ratio of phage to bacteria in the environment, which is 10:1. Yet, viruses are somewhat ignored until there is an outbreak. Shouldn’t they get a better press agent?

Perhaps more virus studies should be published as articles in infection control journals to help educate healthcare personnel about viruses? More focus on viruses in healthcare might reveal more virus involvement in human diseases, and that might lead to better infection prevention and better outcomes.

An article written by Alan Taege at the Cleveland Clinic discusses foodborne disease, and a comment in the article might explain why viral diseases are often overlooked or ignored. Taege writes that, “Viruses are likely the most common cause of foodborne disease but are seldom investigated or confirmed because of the short duration and self-limiting nature of the illness. In addition, the inherent difficulty of laboratory investigation and subsequent cost of viral studies lead to a lack of clinician investigation, and, therefore, overall underreporting. 

In addition to the ‘self-limiting nature of viral illnesses’, bacteria are easily cultured on commercially available agar plates or broth, while viruses require special culture concoctions and methods. Those raise testing costs and increase testing times. (Did viruses plan things that way?)

Also, bacteria are much larger than viruses, making bacteria more easily identified using light microscopes. Bacteria can also be easily filtered and cultured. Viruses require electron microscopes to be seen, special filters for capture and special growth methods using live cells, making them much more difficult to study.

Great size differences between viruses and bacteria explain why viruses require special scopes and special filters. Most viruses range from 20nm to 750nm (about 45,000 times smaller than the width of a human hair), while an E. coli bacterium measures 3,000nm long by 1,000nm wide. Therefore, viruses pass through biologic filters that bacteria cannot. To collect and view viruses requires special filters and an electron microscope, which allows uncollected and unidentified viruses to possibly pose threats to healthcare staff and to patients via underreporting.

So, what does all of this mean to healthcare staff and to patients? Viruses threaten healthcare staff because of their size and numbers. Healthcare staff and some patients use N95 masks for protection from infections. However, N95 respirators provide filtration of aerosolized or airborne bacterial and viral pathogens only when the respirator properly fits the healthcare staff or patient.

Healthcare staff wear additional protective apparel. Historically, protective apparel has been referred to as personal protective equipment (PPE). Staff contamination prior to donning PPE or from improper donning or removal of PPE (including respirators) must be avoided to prevent skin and mucus membrane contamination.

In addition, surgical masks, gowns and garb that fail to prevent blood/body fluid strikethrough, could allow virus passage. The lungs and/or skin of the healthcare worker, which might be protected from bacteria or blood by fluid-resistant protective gear, could possibly be contaminated by viruses that pass around them, for example gaps around surgical masks apparel openings, and needle holes in sewn seam, or land directly onto exposed skin (especially head and neck areas) or mucous membranes (nose, mouth, eyes).

So, how can healthcare staff and patients protect themselves from pathogenic, human viruses? Some of the same practices  that we utilize to protect ourselves from pathogenic bacteria can also help to protect us from viruses: 1) avoid contact with infected individuals, their clothing, bedding, bandages and personal use items (toothbrushes, floss, razors, tissues, etc.) 2) wear PPE  to provide protective barriers against direct contact with infected persons; 3) remove and dispose of PPE in such a way as to prevent self-contamination and wash hands and exposed skin to remove possible viral contamination.
 
A new approach for patient and healthcare staff - neutralization of viruses on hands and skin - is discussed below. Let’s turn now to a new approach to stopping viruses.

Ebola virus can live in water on hospital surfaces for up to six days, where hospital staff and patients can transfer the virus by touching contaminated surfaces with their hands or skin. In dried blood, the virus can be active for up to five days, and up to 14 days in liquid blood. 

Viruses such as HIV, hepatitis, rhinovirus and influenza live outside the body for periods ranging from "cannot survive” (hepatitis C) to ‘can survive a month’ (hepatitis A). One virus, smallpox, can remain viable for years, if not decades. Fortunately, smallpox virus has been eradicated. 

To remove viral contamination from the hands and skin, many commercially available skin antiseptics deactivate and/or remove some viruses from the skin. However, the African Ebola virus outbreak pointed to the need for a new, more economical, non-flammable, spray-on topical skin application designed specifically to neutralize viruses on the skin.

Such an innovative, simple approach has been developed. A topical skin application of aluminum hydroxide and other chemicals generally regarded as safe (GRAS) can possibly provide a preventative virus shield by binding, and thereby altering, the complex protein structure found on all viruses to inhibit their penetration into human cells. Aluminum compounds have been used for millennia. For example, they were used by the Romans as a water clarifying and flocculating agents as early as 77 A.D. 

Here is the way aluminum hydroxide topical skin application works. Particles finer than 0.1 µm (10−7m) in water remain continuously in motion due to electrostatic charge (often negative) which causes them to repel each other. When their electrostatic charge is neutralized by the use of a coagulant chemical, the finer particles start to collide and agglomerate (combine together) via Van der Waals' forces. 

These larger and heavier particles are called ‘flocs’. The agents causing these heavier particles are called flocculants.

Very simply, applying aluminum hydroxide (AlOH) topical skin application agglomerates the viruses on contaminated skin so that the viruses are no longer effective.  It is important to neutralize viruses on the skin because we might touch contaminated areas of our skin and then transfer viruses to our mouth, nose, or other portals of entry.

Theoretically, the AlOH/virus agglomeration flocs interfere with cell binding/genome entry into the cell, thereby blocking viral replication.  Some viruses might bypass the AlOH shield, and the body has natural defenses against small numbers of viruses. Limiting the number of viruses enables the body to better reject viral attacks.  

In summary, viruses are quite amazing, and it is also amazing that a new way to potentially neutralize viruses on skin has been developed by employing knowledge possessed by the ancients.

Milt Hinsch, MS, MBAC, has worked in the medical device industry for 42 years in various positions. He currently works as a technical services director with a major medical device company and advises a start-up company as an unpaid consultant. He says that he enjoys learning and sharing exciting bits of knowledge.   



comments powered by Disqus