What Does Antimicrobial Mean? Agents, Resistance, and Products, Explained

Antimicrobial agents are used in all sorts of products to kill fungi and bacteria. Unlike antibiotics, which are medications designed to kill bacteria within the body, antimicrobial copper and silver can do so outside of the body. Keep in mind that antimicrobial products may kill bacteria and fungi—whereas soap, body wash and other products only kill bacteria.

There is also the issue of antimicrobial resistance: due to the use of antibiotics and other products. In other words, people and product engineers (like us) are increasingly looking to natural alternatives to kill everyday germs.

Here are a few of the main questions, answered in this article:

• Antimicrobial definition
• The differences between antimicrobial, antibiotic and antibacterial
• Products that may have antibiotic or antibacterial properties
• Materials that may kill or reduce the spread of germs
• Guide to antimicrobial resistance and stewardship

The following is meant for educational purposes. Do not take it as medical advice.

Antimicrobial Definition for Beginners

Summary: Antimicrobial agents stop the spread of bacteria, viruses, and fungi. By contrast, antibacterial’s effectiveness is restricted to bacteria and anti-fungals are for fungus only. Antibiotics act inside the body, disinfectants are for surfaces, and antiseptics (or sterilizers) are for skin contact. Disinfectants are typically stronger than sanitizers, which only kill bacteria (not viruses).

Pictured: Coronavirus, or COVID-19, an example of a virus.

You’ve probably heard this term thrown around but may not be sure what it actually means in terms of health and effectiveness. Antimicrobial agents can either kill or stop the growth of microorganisms, which may include bacteria and fungi. These agents may be divided into different categories depending on their applications and origin. These include:

1. Antibiotics
2. Anti-fungals
3. Antibacterials
4. Disinfectants
5. Sanitizers
6. Antiseptics (or sterilizers)

In recent times, some of these terms have become blended. However, antibiotics are reserved for antimicrobial agents that act within the body. Disinfectants are used on surfaces and may kill viruses whereas sanitizers are weaker, and used for killing bacteria (see EPA guidelines). Disinfectants are not meant for human contact whereas antiseptics, typically used in surgery, are. Antibacterial products kill or stop the growth of bacteria, are typically thought of as synthetic (think: disinfectants).

Antimicrobial agents is the overarching term that includes many of these distinctions, though they can vary in terms of application, effectiveness, and accessibility (ex: you need a prescription for antibiotics but not for a bleach disinfectant).

We manufacture several antimicrobial products, including a door handle and iPhone case. These products have both antimicrobial and antibacterial properties, meaning that they may stop the spread of viruses, fungi, and bacteria, not just bacteria.

Pictured: A replica of streptococcus pneumoniae bacteria. The spread of bacteria may be mitigated by antimicrobial and antibacterial agents.

10 Antimicrobial Products

Today, there are soaps, mouthwashes, fabrics, underwear, socks, and many other products that may have bacteria and virus-killing properties. Hand sanitizer is perhaps the most common one, but there is also body wash, toothbrushes, and many more.

We are pleased to announce that we will soon be releasing antimicrobial door handle covers. These silicone products are infused with micronized silver, which we have had third-party lab tested to check its effectiveness against germs. We chose to make these two products given the current state of world health and because these are two of the most frequently touched household items.

7 Examples of Antimicrobial Agents

There are many, many agents used to kill or slow the growth of bacteria, fungus, viruses or a combination of all three. With the discovery of antibiotics, research on alternative forms of antibacterials and antivirals slowed. Only after the troubles with antimicrobial resistance (more on that later), has an interest in copper, silver and other alternatives emerged.

Here are a few different kinds that you may have encountered:

1. Micro-organism-derived antibiotics. Ex: Penicillin.
2. Synthetic antibiotics, which are modeled after the microorganisms and serve to make these medications more widely available. Examples include various cancer, tuberculosis, anti-viral and anti-fungal treatments.
3. Antiseptic and disinfectant agents are the active chemical components that make up products that kill various viruses, as well as bacteria. Examples include Iodine and Boric acid.
4. Antimicrobial agents used in various consumer products include organosilanes, organophenols, and organometallics.
   • Organometallics contain metal atoms.
   • Organisilanes contains silicon (not the same as silicone) and carbon atoms.
   • Organiphenols are organic compounds, especially those found in plants.

Is Copper Antimicrobial?

Copper and copper alloys, like bronze and brass, can stop the spread of bacteria, viruses and fungus in the home, healthcare facilities and the workplace. This is why doorknobs were frequently made from brass in older homes. Note that today, most doorknobs are made from stainless steel, which can host bacteria and viruses, unlike brass.

What does this mean, exactly? Disease can live on an inanimate surface, like a door or iPhone, for days, weeks or even months, according to research published in BMC Infectious Diseases. In other words, substituting a material that can house germs for one that kills them can make a big difference, such an antibacterial door knob cover.

The Science Behind Copper 

The EPA has accepted copper alloy products as antimicrobial following testing. Here are a few other studies on copper, though humans have been using it to stem the flow of viruses and bacteria since 460 BCE, according to research on e coli published in Applied and Environmental Microbiology.

Other research on copper suggests that it is effective on bacteria that causes skin infections, urinary tract infections, staph infections, and other serious conditions, especially those found in hospitals. A study found that substituting commonly-touched surfaces for copper alloys reduced the spread of bacteria and viruses in hospitals by up to 55%.

Hand sanitizer (pictured) may be antibacterial rather than antimicrobial.

Is Silver Antimicrobial?

Silver is another metal that may reduce the spread of bacteria, viruses, and fungus. It has a variety of applications, including bandages, breathing tubes, catheters, and consumer products.

At Silicone Gear, we have produced scuba diving mouthpieces from silicone containing antimicrobial silver. We are also releasing two antimicrobial products: a door knob cover and a silicone iPhone case. You can see the lab test results for our material among our manufacturer Casco Bay Molding’s certificates.

The Research on Silver

Similar to copper alloys, silver has been used to reduce the spread of bacteria and viruses—long before the advent of penicillin.

• Research has found that endotracheal tubes coated in silver reduce the risk of contracting pneumonia.
• Another study found that silver reduced the risk of UTI contraction in catheters.
• Antimicrobial silver also has a long history in water purification and surgical applications, according to this review.

How does silver work? In essence, silver ions interact with bacteria and virus cell membranes. By attaching to these members, the ions can either stop their growth or fully kill the cell, transforming it into a agent that can kill other cells just like it.

Antimicrobial Silver and Silicone

We use silicone with micronized silver to produce our antimicrobial iPhone case and door knob covers. Both materials—silver and silicone—are known for their biocompatibility, i.e. do not harm the human body with contact, and their versatility. In launching our antibacterial product line, we chose to develop solutions to reduce the spread of germs on two of the most frequently touched household items.

Prior to this, we designed and produced antimicrobial scuba mouthpieces.

What Is Antimicrobial Resistance?

Antimicrobial resistance is a common problem in modern life. It occurs when parasites, viruses, fungi and bacteria morph in response to antibiotics and antimicrobial agents. In other words, the overuse of these products may create super-bacteria for which there is little treatment. This may result in dangerous cases of tuberculosis, HIV, influenza and other life-threatening illnesses.

Note that silver and copper do not cause antimicrobial resistance as it is defined today. This has led to their re-emergence in contrast with synthetic and organic antibiotics.

What Causes Resistance?

Over time, it makes sense that diseases will adapt. However, there are a few things that may accelerate this process. These include:

• Over-prescribing antibiotics
• Giving livestock antibiotics
• Over-use of antimicrobial products in day-to-day life.

For that reason, we’ve developed modern-day solutions that utilize silver, not synthetic alternatives that may have a dangerous long-term global health cost.

Antimicrobial Stewardship: How to Help

In recent years, there has been a movement to slow the evolution of viruses and bacteria into super-viruses and super-bacteria. Stewardship means avoiding products when that further resistance when possible—such as antimicrobial products that are not silver or copper. It also entails avoiding the over-prescription of antibiotics and over-use in livestock.

Antimicrobial Silver Solutions in 2020

We are dedicated to perfecting American-made silicone products with antibacterial capabilities. This means understanding the history of bacteria, virus, and parasite prevention and its legacy if we do not practice stewardship. For that reason, we are pleased to introduce our door knob cover and silicone iPhone case, both with bacteria and virus-killing properties.