Home » Blog

Disinfection in the hospital environment: results of a survey part II

Preface

Novapura had an independent company conduct a survey on the topic of “disinfection in hospitals” in May 2022. Institutions in Switzerland were surveyed.  (Compare also the blog from 15.7.22)

Questions and answers

masa cases per year Swiss hospitals

  • 41% of the institutions had no cases to fight.
  • 41% of the institutions had more than one case to fight, 18% of the institutions had to deal with more than 20 cases per year.

mrsa disinfection method - novapura

In more than 80% of the institutions, manual surface disinfection is also used in these cases. In other words, disinfection is done by hand. Despite obvious deficiencies, such as

  • lack of process safety, i.e. the quality of the disinfection is left to the good will of the person carrying it out
  • the process is labour-intensive and takes a long time

mrsa documentation swiss hospital

23% of the institutions report that the disinfection process is not documented at all, in 62% of the institutions it is documented, but only in just under 20% of the cases there is a central filing system.

In order to make a process safe and reliable, a clear documentation is indispensable. It is only through the evaluation of this documentation that errors can be detected and corrected. Over time, the process becomes more stable and the quality improves sustainably.

who disinfects contaminated hospital rooms

What is astonishing from our point of view is the answer to the question of who carries out the decontamination after an attack of multi-resistant bacteria: It is essentially internally trained staff. In times of scarce human resources, it is worth considering whether it is not better to outsource this process completely. A professional, external service provider is faster and more experienced than internal staff, who (according to this survey) only carry out decontamination every second week at most. Added to this is the experience with personal protective equipment, which requires special attention when carrying out such complex and potentially dangerous work.

An alternative is the use of automatic systems, which are very easy to operate and require a minimum of personal protective equipment. This can massively increase the efficiency of the internal staff, because the systems work autonomously; during this time the operator can pursue another task.

Biggest challenge in today’s disinfection practice?

The following three key issues have been identified as the biggest challenge:

  • The process is personnel and cost intensive
  • Lack of records of disinfections performed
  • Risk of infection and spread in the building

Findings

We see a lot of optimisation potential in the disinfection of rooms when they need to be decontaminated.

Automatic disinfection versus scrubbing and wiping disinfection by hand.
careful use of human resources through automation or consistent outsourcing of the process
stringent and consistent documentation versus decentralised, sometimes paper-based documentation. Learning cycles can be shortened, which benefits the staff and the patients.
Digitalisation must also find its way into this process.

Manual surface disinfection – widely used despite shortcomings

Preface

Novapura had an independent company conduct a survey on the topic of “Disinfection in hospitals” in Swiss healthcare facilities in May 2022. One of the main topics was the method of surface disinfection. The following methods were available for selection:

  • manual surface disinfection with microfibre or cotton cloth
  • room disinfection by fogging
  • room disinfection by spraying
  • room disinfection by UV

A further question concerned the event of contamination. We distinguished between two cases:

  • standard disinfection, which is carried out regularly, and
  • the extraordinary decontamination of a room, triggered by a multi-resistant bacterium or a virus.

Results

Manual surface disinfection is indicated as a method in 100% of the responses when it comes to regular standard disinfection. This includes rooms such as quarantine rooms, operating theatres, toilets for staff and patients, or patient rooms. The treated room can be used again immediately. The disinfection process is not documented.

Manual surface disinfection is indicated as a method in 85% of the responses when it comes to decontaminating rooms. In a few cases, those responsible use a UV device, or they carry out room disinfection by fogging. The room cannot be used for up to one day. The disinfection process is partially documented.

Findings

Manual surface disinfection is still the measure of all things, despite obvious deficiencies such as

  • personnel-intensive process, as a result
  • low process reliability.
  • lack of documentation, leading to
  • no possibilities to improve quality.

Neither automation nor digitalisation have found their way into this process.

Multi-resistant bacteria – in the shadow of SARS-Cov2

Multi-resistant bacteria are bacteria with multiple resistances against which most antibiotics have become ineffective.

Antibiotics fight bacteria and are used to treat life-threatening infectious diseases such as pneumonia. However, due to mass and improper use, more and more bacteria are becoming insensitive to many antibiotics today. Mass use also includes the administration of antibiotics to animals 1) and partly (until 2008 also in Switzerland) in agriculture. 2)

The occurrence of multi-resistant bacteria is particularly frequent and feared in the hospital environment. Hospital infections often occur in connection with a stay in a healthcare facility. According to older estimates, such infections lead to about 70,000 cases of illness and 2,000 deaths per year in Switzerland alone. In comparison, in the years 2020 – 2022 (as of May), approximately 6,335 corona deaths per year have been recorded.

The most important types

Methicillin-resistant staphylococcus aureus (MRSA). The most important transmission route for MRSA is direct transmission between people, especially via the hands. Another route of transmission is via contaminated objects, as well as from animal to human. 3.)

A distinction is made between hospital-associated MRSA, population-associated MRSA (transmission outside the hospital environment from person to person) and livestock-associated MRSA (common in livestock such as pigs, cattle and poultry; transmission from animal to human is possible).

MRSA bacteria
MRSA bacteria

 

 

 

 

 

 

 

 

Carbapenemase-producing enterobacteria (CPE): Multi-resistance to the antibiotics penicillins, cephalosporins, monobactams and carbapenems. Transmission with direct or indirect contact (faeco-oral). CPE is mainly transmitted through contact infection via the hands (e.g. starting from faeces and infected wounds). Resistant germs can also be transmitted to humans through contact with farm animals or from the environment of food such as fruit and vegetables. Transmission at hospitals and other health facilities is possible 4) There is an obligation to report.

CPE bacteria
by NIAID – Klebsiella pneumoniae bacteria

Vancomycin-resistant enterococci (VRE) These are enterococci with resistance to the reserve antibiotic vancomycin. VRE can survive not only in the intestines, but also on the skin and hands of patients (and medical staff) and in the patient’s environment. Therefore, without good basic hygiene and additional transmission control measures in risk areas, they are easily transmitted from patient to patient. This risk is particularly high when patients have diarrhoea, because large amounts of the pathogens then enter the environment (nappy, bedpan, toilet, toilet seat, commode, etc.). Likewise, transmission can occur on a patient himself through contact with contaminated materials and subsequent aseptic activity.

Prevention / Measures

  • Robust early detection process implemented
  • Consistent admission screening for patients at risk
  • Contact isolation for cases that occur
  • Disinfection of the affected rooms, including documentation.

  1. https://www.blv.admin.ch/blv/de/home/tiere/tierarzneimittel/antibiotika.html
  2. https://www.agroscope.admin.ch/agroscope/de/home/themen/pflanzenbau/obstbau/feuerbrand/projekte/pflanzenschutz.html
  3. https://www.infektionsschutz.de/erregersteckbriefe/mrsa/#c3832
  4. https://so.ch/verwaltung/departement-des-innern/gesundheitsamt/kantonsaerztlicher-dienst/infektionskrankheiten/multiresistente-bakterien/carbapenemase-produzierende-enterobakterien/
  5. https://www.swissnoso.ch/worum-geht-es/healthcare-assoziierte-infektionen

AFNOR Test

AFNOR NFT 72-28

AFNOR NFT 72-28 is the name of a French test standard. It has established itself as the standard method for testing the effectiveness of autonomous room disinfection systems. It is known for its particularly strict compliance conditions. Many suppliers of disinfection systems are deterred by this rigorous and expensive test; it is therefore not surprising that only about 30% of the systems offered on the market have passed the test. It is important in this context that the entire system, i.e. the disinfectant and the device are tested together.

A distinction is made between “automatic application” and “directed spraying”.

Direct spraying

afnor

 

 

 

 

 

 

The disinfectant is sprayed onto a test surface from a predetermined distance. The sample plates are located on this surface. The test germs are applied to these sample plates. Germs can be bacteria, fungi, yeasts or viruses.

Automatic application

afnor test

 

 

 

 

 

 

 

The device to be tested is placed in a defined room. The disinfectant is fogged fully automatically into the room, an thus onto all surfaces. In contrast to directional spraying, the sample plates are located on the back of the test surface. (see picture above). The aerosols generated by the device must therefore be applied in such a way that they not only touch the test surface facing the device, but also the test surface facing away from the device.  The sample plates are placed somewhere in the room.

The AFNOR test is very close to reality, if one compares the set up of the test and, for example, a patient’s room  in which furniture, equipment, etc. is placed randomly.

Systeme with UV-light and AFNOR

Disinfection systems that are operated with UV-C light can never fulfil the AFNOR test. Because the sample plates are on the dark side of the test surface, the emitted UV rays never reach the test germs. Even automatic or autonomous movement of the device does not help, because the sample plates are placed so close to the wall that they are always in the shadow.

aseptobot

The aseptobot, which we developed recently passed the AFNOR test successfully. The disinfectant fog-it plus was used in the test.
aseptobot afnor

 

 

 

 

aseptobot

 

Contact transmission of SARS-CoV-2

There is extensive literature on the transmission routes of SARS-CoV-2. Essentially, two transmission routes are distinguished: airborne and contact transmission via contaminated surfaces.

Airborne

Transmission occurs through larger droplets and small aerosols, which are transferred from one person through breathing, coughing, talking, singing and sneezing to another person who inhales the droplets or aerosols.

Droplets fall to the ground relatively quickly, while aerosols “stay” in the air for a relatively long time. What does “relatively” mean?

The air we breathe consists of droplets between 0.2-20 µm. [1] It can be shown that for a person 175 cm tall, it takes about 20 seconds for the large droplets of breath to fall to the ground. The small aerosols reach the ground only after a very, very long time (days). These are theoretical considerations which do not take into account environmental influences such as temperature (evaporation), speed of the ambient air and pollution of the air.

When sneezing and coughing, the horizontal velocities of the aerosols are much higher than the sinking velocity, i.e. during the descent these aerosols are also carried very far. The video at the following link shows impressive pictures of how aerosols can be carried up to 8m. These droplets settle on surfaces and can lead to contact transmission.

SARS Cov aerosol
Picture from [7]

Contact transmission

The authorities in Switzerland, Germany and Austria therefore do not rule out contact transmission:

FOPH, Switzerland: When infected persons cough and sneeze, infectious droplets get onto their hands or onto neighbouring surfaces. Another person could become infected if they pick up these droplets with their hands and then touch their mouth, nose or eyes. [2]

RKI (Robert Koch Institute), Germany: Transmission through contaminated surfaces cannot be ruled out, especially in the immediate vicinity of the infectious person [3].

Federal Institute for Risk Assessment: Furthermore, transmission via contact or smear infections cannot be ruled out. In this case, pathogens that are on the hands reach the mucous membranes of the nose or the eye, where they can lead to an infection [4].

Austrian Health Office: the novel Corona virus can also adhere to the skin and on objects (e.g. door handles, telephone) and be transmitted via hands (smear infection) – especially if hands with virus particles come into contact with the eyes, nasal or oral mucosa. [5]

How long do viruses that reach surfaces via droplets remain infectious?

The much-cited reference literature [6] on this point can be found under the following link. The authors have investigated how long SARS-CoV viruses remain infectious on different materials. Copper, cardboard, stainless steel and plastic were examined. The pure aerosols in the air were also examined. The summary of the results can be seen in the following graphs:

SARS Cov Materials

The result of the study in brief:

  • SARS-CoV viruses remained infectious in the air for the entire experiment duration of 3 hours.
  • On the tested materials, the viruses remained infectious for up to 72 hours, although the viral load decreases significantly over time.
  • On copper and cardboard, the viral load decreases faster than on plastic or stainless steel.

Literature

  1. https://www.aerzteblatt.de/archiv/217048/SARS-CoV-2-und-Aerosole-(1)-Was-wir-bis-heute-wissen
  2. https://www.bag.admin.ch/bag/de/home/krankheiten/ausbrueche-epidemien-pandemien/aktuelle-ausbrueche-epidemien/novel-cov/information-fuer-die-aerzteschaft/schutzmassnahmen.htmlübertragung
  3. Epidemiologischer Steckbrief zu SARS-CoV-2 und COVID-19 Stand: 19.4.2021
  4. https://www.bfr.bund.de/cm/343/kann-das-neuartige-coronavirus-ueber-lebensmittel-und-gegenstaende-uebertragen-werden.pdf
  5. https://www.gesundheit.gv.at/krankheiten/immunsystem/coronavirus-covid-19/uebertragung
  6. Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1, N Engl J Med 2020; 382:1564-1567