Antisepsis and asepsis

The antisepsis It is the procedure that is carried out to reduce or eliminate microorganisms on living beings and the asepsis are the procedures that seek to destroy microorganisms that may be contaminating inanimate objects or surfaces.

Both asepsis and antisepsis are different approaches applied in places where the presence of microbes must be avoided, such as clinical laboratories, hospitals, and the food industry. These microorganisms can cause infections and put human health at risk..

	Antisepsis	Asepsis
Definition	Removal or destruction of microorganisms on living beings.	Destruction of microorganisms on surfaces or inanimate objects.
Utility	Prevent wound infections by microorganisms in the body or the environment.	Eliminate contamination by pathogenic microorganisms.
Agents used	Antiseptics, detergents and soaps	Disinfectants, sterilization
Examples	Washing the mouth with antiseptic agents when performing a dental procedure.	The use of sterile material in a dental procedure.

What is antisepsis?

Antisepsis is the elimination and / or reduction of microorganisms on the skin or mucous membranes of living beings. Micro-organisms, such as bacteria and fungi, normally inhabit the skin and mucosal surfaces (such as the inside of the mouth). When a surgery is performed, a tooth is extracted, or we have an injury, these microorganisms can cause infections.

The term "antisepsis" derives from the Greek sipsis which means "putrefaction" and the prefix anti which means "against". Antisepsis would come to mean something "against putrefaction".

For example, in surgery, doctors and nurses:

1. They wash their arms with antiseptic agents,
2. They wear gloves and other clothing to avoid contaminating the patient with their microbes.
3. The patient, in turn, is treated with antiseptic agents in the incision or cut area, to prevent their own microbes from entering the body and causing an infection..

When we cut ourselves, we do antisepsis when we wash the wound and put alcohol or povidine on it, all this with the intention that the wound does not become infected.

Antiseptics and their mechanism of action

Antisepsis is applied in situations where microorganisms can normally be found. Chemicals called antiseptics are used to kill or slow the growth of microorganisms. Among the most common antiseptics we have:

• The alcohol: they act by denaturing proteins and are active against Gram-positive and Gram-negative bacteria, some fungi and viruses.
• Chlorhexidine: acts by breaking the cell wall of microorganisms. It is effective with Gram-positive bacteria and some fungi.
• Iodine and iodinated compounds (povidine, betadine): they act by breaking down the cell wall and stimulating the oxidation of compounds.

Some factors should be considered when choosing the right antiseptic:

• The properties of the agent: its spectrum and speed of action and persistence.
• Your safety: that it is not a corrosive agent to the skin.
• Its acceptance: the presence of emollients, perfumes and degree of absorption.

What is asepsis?

Asepsis is defined as the absence of infectious organisms. It is also the process or procedure carried out under conditions in which contamination by microorganisms is reduced..

The word "asepsis" comes from the Greek prefix for negation to (no) and the word sipsis or sepsis which means "putrefaction". The etymological definition would be absence of putrefaction.

For asepsis, a set of hygiene methods and procedures is carried out in a given environment, in order to avoid contamination of it by infectious and pathological agents..

Aseptic techniques

Aseptic techniques are intended to eliminate microorganisms and thus prevent contamination. Some of the aseptic measures include the following: sterilization of objects, cleaning of all areas, application of isolation techniques, use of appropriate clothing and utensils.

Cleaning and washing

It is the process of removing organic waste. It is carried out using detergents and washing with water.

Disinfection

It is the process of eliminating microorganisms on objects using chemical agents known as disinfectants.

Disinfectants are classified according to their activity in:

• High activity disinfectants: destroy all microbes and spores, except when they are in large quantities.
• Intermediate disinfectants: they are active against microbes but not against bacterial spores.
• Low disinfectants: they are active only against some viruses and bacteria.

Some viruses and prions are not affected by disinfectants.

Sterilization

Sterilization is the process of removing all microbes, including bacteria, spores, viruses, and fungi. Several sterilization processes are used:

1. Water steam: this method allows the eradication of viruses, bacteria such as tuberculosis bacteria Mycobacterium tuberculosis and heat resistant spores. An equipment called autoclave is used, which combines high temperature, pressure and a long time (134ºC at a pressure of 2 kPa for 3 minutes or 121 ºC at a pressure of 1 kPa for 15 min).
2. Hot air sterilization: this is an inefficient method. To kill all microorganisms, apply 160ºC for 2 hours. Applies to non-aqueous liquids and non-stainless steel instruments where it is necessary to prevent corrosion of sharp edges (for example, ophthalmic instruments).
3. Ethylene oxide sterilization- This method is widely used in industry on heat sensitive items such as endoscopes and electrical equipment. Ethylene oxide is a non-corrosive gas, but it is toxic, carcinogenic, and flammable..
4. Sterilization with low temperature steam and formaldehyde: This method uses dry saturated steam and formaldehyde at 73ºC. It has action against bacteria, spores and most viruses. The low temperature allows it to be used on items that are sensitive to heat or with plastic parts.
5. Sterilization by irradiation- This is an industrial process used to sterilize batches of single-use products, such as syringes, sutures, and catheters. Gamma rays or accelerated electrons are supplied at a dose of 25KGy.

You may be interested in seeing epidemic, endemic and pandemic.

Historical perspective of antisepsis and asepsis

At the end of the 18th and 19th centuries, mortality was very high when surgical procedures were performed, not because of procedural failures but because of post-operative infections..

In the mid-19th century, Oliver Wendell Holmes and Ignaz Semmelweis recognized that many hospitalized women died after childbirth from puerperal fever. This was the case with women cared for by medical students who had previously been to the morgue. So, a strict hand-washing regimen was implemented that reduced mortality in these cases to 1.3% in 1848..

Louis Pasteur discovered that bacteria caused damage to wine. This inspired the English surgeon Joseph Lister (1827-1912) to consider the role of bacteria in human disease. In 1865, Lister began applying phenol (a substance used in the treatment of sewage) as an antiseptic to wounds and hand washing in surgical procedures, reducing deaths from infections..

In 1889, the American surgeon William Stewart Halstead (1852-1922) noticed that one of his nurses was allergic to hand washing antiseptics and ordered gloves from the Goodyear Rubber Company. Since then, the practice of wearing gloves has been standardized to protect the patient as well as surgeons and assistants..

More recently, there is the discovery of antibiotics and their prophylactic use and positive pressure laminar air flow systems in reducing post-surgical infections..

You may be interested in knowing about:

• Virus and bacteria
• Archeas and bacteria
• Difference between isolation and quarantine.