How to neutralise and inactivate viruses
MEIKO TopLine awarded "Virucidal activity" classification
Viruses can only be seen under an electron microscope. They are highly efficient replicators and, in the worst case, their effects can be fatal. The good news is that hospitals and care homes can effectively tackle viruses on bedpans and urine bottles by using MEIKO washer-disinfectors.
Viruses – non-living entities with impressive survival skills
Measuring just a few hundred nanometres in diameter (1 nanometre = 0.000001 millimetre), viruses consist of genetic material surrounded by a protein coat and are not, strictly speaking, living organisms. Since they do not have a cell structure, viruses cannot carry out metabolism on their own. They lack the ability to reproduce on their own, so must find another way to ensure their replication.
A virus does this by commandeering the cells of a host organism. It injects its viral genetic material into the host cells and reprograms them to make copies of itself. When the new viral particles are released from the host cell, the host cell is destroyed, either by the virus itself or by the host organism's immune system.
There are two types of viruses: enveloped viruses – which are surrounded by a lipid (fatty acid) envelope – and non-enveloped or "naked" viruses.
Another peculiarity of viruses is that since they are not alive, they can't strictly speaking be killed. They can, however, be inactivated, i.e. rendered harmless!
Enveloped viruses
Structure
- RNA or DNA (genetic material)
- Capsid (protein coat)
- Membrane (lipid envelope)
Examples
- Genital herpes virus
- Viruses that may be excreted in the stool, such as coronaviruses and influenza viruses
- Other viruses, such as e.g. HIV
Classification of efficacy:
- "Active against enveloped viruses" or
- "Limited spectrum of virucidal activity" or
- "Virucidal activity"
Non-enveloped viruses
Structure
- RNA or DNA (genetic material)
- Capsid (protein coat)
Examples
- Hepatitis A virus
- Entero-, noro-, rota- and adenoviruses
- Anal and genital human papillomavirus
Classification of efficacy:
- "Limited spectrum of virucidal activity" for efficacy against adeno-, noro- and rotaviruses or
- "Virucidal activity" for efficacy against all viruses (i.e. enveloped and non-enveloped viruses)
Incredibly resistant
Although it may seem counterintuitive, non-enveloped viruses actually exhibit greater resistance than enveloped viruses against chemical and physical inactivation methods and environmental influences.
What is the weak point of an enveloped virus? Its viral envelope! Thanks to its high lipid content, the envelope can be destroyed relatively easily by fat-dissolving substances, alcohols, and even by detergents. That makes enveloped viruses easy to inactivate.
Non-enveloped viruses are much more resistant to inactivation. Stronger weapons are required to deal with these types of virus. In fact, the only way to achieve the desired result is by using special active substances, often in very high concentrations, in combination with additional measures in a cleaning and disinfection process.
It therefore makes a big difference whether you wish to inactivate only enveloped viruses, or all the viruses that are present in a medical setting. Enveloped viruses can be killed by disinfectants classified as being "Active against enveloped viruses". But effective activity against all viruses (i.e. against both enveloped and non-enveloped viruses) can only be achieved by agents and methods that fall in the "Virucidal activity" category.
The presence of an envelope determines a virus's resistance.
Some non-enveloped viruses are marginally easier to inactivate than others. This led to the establishment of a further efficacy classification, "Limited spectrum of virucidal activity". Disinfectants in this category are effective against enveloped viruses and certain non-enveloped viruses (see table). As such, they fall somewhere in between the "Active against enveloped viruses" and "Virucidal activity" categories.
People need protection they can rely on
One of the biggest challenges for infection-control staff in hospitals, clinics, retirement homes and care facilities is dealing with viruses that can be transmitted through multiple routes, including via contaminated surfaces, hand contact, and droplets expelled when speaking or coughing.
These viruses, which are responsible for numerous diseases in humans, are invisible to the human eye and, in many cases, extremely difficult to inactivate.
Not just safe, but fully virucidal
The independent, accredited test laboratory HygCen Germany GmbH carried out a study adapted to the relevant applications on the basis of EN 17111 and EN ISO 15883-3. Their experiments confirmed that the new MEIKO TopLine series of appliances satisfies the requirements for "Virucidal activity" classification.
This means that whatever human pathogenic viruses are present on care utensils, MEIKO can help tackle the problem effectively.
"In accordance with European standards, we conducted these tests using an extremely temperature- and disinfectant-resistant test virus. If a process can inactivate this virus, it will also work on a whole series of other pathogens that are much easier to inactivate. We know this because this particular test virus is resistant to heat, disinfectants, environmental influences and other factors. And that's what makes this study so valuable."
Professor Dr. Dr. Friedrich von Rheinbaben, virologist
For this purpose, the test virus was applied to urine bottles and bedpans, which were then cleaned and disinfected in the MEIKO TopLine using the intensive programme, which includes a total of five cleaning steps plus a final thermal disinfection stage with an A0 value of 3,000. The results revealed a greater than four-log reduction in the test virus load, equivalent to a reduction in pathogens of over 99.99 percent. In other words, after processing, the care utensils no longer posed any risk of infection within the definition of DIN EN 17111.
Practical tests on the basis of EN ISO 15883-3 and EN 17111
Testing of the cleaning and disinfection process was carried out under realistic conditions in accordance with the EN ISO 15883-3 standard for the cleaning and disinfection of bedpans and urine bottles. The minimum requirements for the efficacy of chemical disinfectants and disinfection processes for instruments according to EN 17111 also apply to appliances that are used to disinfect instruments by immersion or rinsing, and in particular to areas and conditions where disinfection is required for medical reasons.
The MEIKO TopLine achieved a greater than four-log reduction in the test virus load, equivalent to a reduction in pathogens of over 99.99 percent.
Along the hygiene chain
In addition to its washer-disinfectors, the MEIKO range of products for the main areas of application also includes modular products and services along the entire hygiene chain:
- Doyen detergents and rinse aids are specifically approved for use in MEIKO washer-disinfectors.
- Even the best technology needs to be used in the right way to get optimum results. Training in how to operate MEIKO appliances is available from the MEIKO Academy.
- MEIKO's offerings also include comprehensive advice and customer-focused service.
