A Are hydroalcoholic hand disinfectant gels really effective against contagion? What is that bactericidal, fungicidal or virucidal activity? What are the differences between an antiseptic and a disinfectant?

All these questions may come to mind due to the global crisis that the coronavirus (SARS-CoV-2) has generated with COVID-19, when we have a disinfectant gel in our hands or when someone from our environment tells us all the benefits or the need to use them. But … are they really effective? Would they kill viruses if we got our hands on it? We explain the actions and contraindications of the most used antiseptics and disinfectants.

What are the differences between an antiseptic and a disinfectant? Do they serve the same purpose?

  • An antiseptic is a substance that inhibits the growth or destroys microorganisms on living tissue , that is, on the skin.
  • A disinfectant is the substance that performs the same action but on inanimate surfaces , that is, on objects that we can touch.

Therefore, the difference lies in whether we use the product on the skin or mucosa or if we use it on inanimate objects , but there are substances that can be used as antiseptics or disinfectants because their mechanism of action is the same when they are on inanimate objects or when they are on the skin. As long as they do not lose activity due to contact with organic matter, and they do not produce toxicity on the skin or by systemic absorption.

Bactericidal, virucidal, fungicidal, bacteriostatic …?

Not all disinfectants or antiseptics have the same spectrum of action, that is, not all inhibit growth or kill the same microorganisms. 

  • A bactericidal substance causes the destruction of a certain bacteria . It kills bacteria … as the coronavirus is a virus, a bactericidal substance would not be effective to prevent contagion.
  • A bacteriostatic substance does not cause the death of bacteria, but prevents their reproduction and growth , the bacteria age and die without leaving offspring, helping to control the infection.
  • A virucidal substance does kill viruses . It depends on the potency it will kill different groups of viruses. In the case of the coronavirus, as it is a new virus, it is not yet known for sure why substances are destroyed or not.
  • A fungicide kills fungi and prevents their reproduction.

What are the most frequently used antiseptics? Action and necessary concentrations of antiseptics and disinfectants

In the following table we detail the main antiseptic and disinfectant agents contained in hydroalcoholic gels or preparations for disinfection of the hands that are in such demand (in many cases exhausted) because of the alarm that the coronavirus is causing.

Ethyl alcohol / Ethanol Good bactericideVariable action against lipophilic viruses and fungiAt 70% it is much more effectivethan 96%It has a variable efficacy against fungi and viruses.
Hydrogen peroxide (H2O2)Broad germicidal spectrum, butvariable activity according to species 6% (20 volumes) as an antiseptic NOT
Chlorhexidine gluconateBactericidal against Gram + and Gram-It is not virucidalAlcohol increases its effectiveness 0.5% formulated together with 70% ethyl alcohol for preoperative disinfection1% solution for wound disinfection NOT 
Benzalkonium chloridePotent bactericide more against Gram + than against Gram-Active against viruses and fungi with lipid content0.1-0.2% solutions for use on healthy skin and small wounds NOT 

Can pharmacies formulate a hydroalcoholic gel as a cosmetic (without sanitary registration)?

Due to the current shortage of hydroalcoholic hand sanitizing gels, many community pharmacists and Official Associations of Pharmacists have consulted the General Council of Official Associations of Pharmacists about the possibility of manufacturing these products from the laboratories of pharmacy offices.

Hydroalcoholic gels intended for hand hygiene can be formulated as cosmetics from the pharmacy as  long as all legal requirements are followed , which are different from those necessary to make a magisterial formulation.

These cosmetic hydroalcoholic gels must NOT claim actions of sanitary or biocidal products for human hygiene, such as disinfectant, antiseptic, bactericidal, fungicidal, yeasturicidal, mycobactericidal, virucidal, etc.

To carry out any elaboration of hydroalcoholic gels that want to be declared as a sanitary product with a virucidal objective, it must be subject to current regulations (eg UNE-EN-14476) and the AEMPS registry.

Finally, any medical prescription in which the composition of a hydroalcoholic gel is duly prescribed may be prepared as a magisterial formula in pharmacies.

From we recommend: 

  • The most important thing is to wash your hands frequently between 40-60 seconds . In addition to complying with all the measures that we already know to avoid contagion.
  • If, in addition, after washing our hands we can use a perfect hydroalcoholic gel, but we must be aware that by using a disinfectant gel we cannot ignore the measures to avoid contagion that we all know. We must not lower our guard because we are using a disinfectant gel. It is easy, unconsciously, that after using a disinfectant gel we don’t worry and we do not remain alert.
  • If we have a hydroalcoholic disinfectant gel and we are going to use it, it is very important to read the product label because:
    • For a hydroalcoholic gel to claim virucidal action (which is what interests us in this case), the manufacturer must show the AEMPS (Spanish Agency for Medicines and Health Products) registration number on the label . We will be using a Medical Device .
    • If we buy a hydroalcoholic gel without this registration number, it will not be a medical device, but a cosmetic product , and you will not be able to claim any action on bacteria, viruses, fungi, spores , etc.
  • Registration with the AEMPS, which depends on the Ministry of Health, is the endorsement of the approval of your indications by the Ministry.
  • In addition to being registered with the AEMPS, the antiseptic gel or hand sanitizer must comply with the UNE-EN-14476 standard. If you do not meet these two requirements, we will not be sure that the hand gel we are using has a virucidal action (against coronavirus). The activity of the gel can only be corroborated on the labeling.

In summary…

It is better to use disinfectant and antiseptic hydroalcoholic gels that are registered with the Spanish Agency for Medicines and Health Products. Gels that on their labeling do not indicate an AEMPS registration number or that comply with the UNE-EN-14476 standard cannot demonstrate that they have activity against bacteria, viruses, fungi, spores, etc.

The use of a hydroalcoholic gel with bactericidal and virucidal properties should not deactivate the alarm and we must maintain the same precautions and follow the recommendations to avoid contagions.

These gels tend to dry out and irritate the skin due to their concentration in alcohol, so it is advisable to hydrate your hands and nails with specific moisturizers.