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Healthcare Associated Infections (HAIs)

Part 2 – Airora’s Hydroxyl Diffuser Technology

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“It may seem a strange principle to enunciate, as the very first requirement in a hospital, that it should do the sick no harm”

Florence Nightingale, 1859

1. Introduction

While material improvements have been made in reducing the occurrence of Healthcare Acquired Infections, they remain a significant risk to patients and carers and a disruptive and costly problem for healthcare providers.

While a major focus of improvement has been on implementing infection prevention protocols, hand hygiene, antimicrobial stewardship and environmental cleanliness some new technologies have been tested in the hope of reducing the incidence of HAIs.

Those technologies are sometimes small and personal, such as automated hand hygiene monitoring and touchless technology. Others are more expansive such as fluorescent marking of high-touch surfaces to ensure cleaning, copper germicidal surfaces and antimicrobial textiles. Such incremental improvements are of course welcome, and each may have a material impact, but even collectively they will not be transformative.

Prompted primarily by the COVID crisis some more ‘whole room’ decontamination technologies have also been considered.

2. ‘Whole room’ decontamination technologies

The advent of COVID-19, and the recognition that the spread of COVID-19 occurs primarily via airborne particles and droplets, has resulted in ‘whole room’ experimentation of both air filters to remove pathogens from the air and mobile radiant UVC devices to inactivate both airborne pathogens and those on surfaces in the direct line of sight of the device.

Portable air filters

The UK’s Scientific Advisory Group for Emergencies (SAGE) considered the potentially beneficial role of portable air filters in some detailed their 2020 report. They concluded that certain types (HEPA, Enclosed UVC) may reduce airborne transmission risks in poorly ventilated spaces but do not lead to a material improvement in a well-ventilated space. The reasons SAGE gave for this fundamental lack of enthusiasm was not just that their impact was both slow and very modest but that they were location sensitive, can inadvertently spread the virus and are, if sized appropriately, noisy.

Indeed, a more recent comprehensive review by the University of East Anglia, of a wide a range of filter types, in applications ranging from air conditioning to portable units, found no evidence that such filter devices prevent transmission of respiratory or gastrointestinal diseases.

Radiant UVC air cleaners

While radiant UVC devices are often considered to be more effective across an entire room than portable air filters, they have their own significant drawbacks:

They emit intense UVC germicidal light that is dangerous to human beings, which requires trained personnel to ensure that the space to be treated is both secure and empty of people.
They only destroy pathogens in a direct line of sight and will thus usually require repeatedly moving to various locations in a room.
Their most significant drawbacks are not just the high cost, but also the simple fact that as soon as they are turned off and moved to the next room, microorganisms rapidly re-contaminate the space.

Radiant UVC devices may have a niche purpose, but in terms of general use to prevent HAIs they are expensive to buy and operate, but neither practical nor effective in use.

Improved Ventilation

The unsuitability of both air filters and radiant UVC to address the HAI challenge, and particularly COVID transmissibility, resulted in SAGE and ASHRAE shifting focus to improving ventilation in currently poorly ventilated spaces, especially where there is a high density of occupation, such as there might be in restaurants, theatres or lecture halls.

However, improving ventilation, especially in existing healthcare buildings, is a specialist, complex and very costly matter, and even where implemented, any improvement in the frequency of HAIs is likely to be strictly limited as the results only potentially reduce airborne transmission, but not direct or via surfaces transmission.

While newer Standards, such as ASHRAE 241, 170 and 62.1, may propose high air change, high cost, high CO2 emissions dilution strategies, these strategies are made redundant by Airora’s breakthrough technology which provides an altogether far more effective and affordable solution.

3. The advent of the ‘Hydroxyl Diffuser’

A new molecular air and surface sanitising technology, the ‘hydroxyl diffuser’, is set to revolutionise our defences against HAIs and future pandemics.

The hydroxyl diffuser is not a filter, rather it replicates a natural outdoor molecular cascade reaction that spreads hydroxyl radicals throughout an entire room in seconds, destroying or neutralising all types of pathogens, moulds, allergens and odours and most other irritants and harmful pollutants, both in the air and on surfaces. Hydroxyl radicals (often just called ‘hydroxyls’) are highly reactive molecules of oxygen and hydrogen (OH) that are continuously produced in abundance in the lower atmosphere.

Hydroxyls are lethal to all harmful viruses, bacteria and mould spores, including all of those that commonly cause HAIs⁴, such as SARS-CoV-2, MRSA, MSSA, C.difficile, E coli, Salmonella, Norovirus and Flu Virus — both in the air and on surfaces.

The Hydroxyl Cascade reaction condenses and preferentially coats the surfaces of viruses, bacteria, particles, and surfaces in general, with abundant hydroxyls; the hydroxyls rapidly inactivate the underlying bacteria, viruses and moulds.

Hydroxyls are incredibly reactive and, as the hydroxyl diffuser produces a never-ending supply, even clumps of cells, thick layers and heavy cell walls (such as TB and spores) will eventually succumb.

Humans, animals, insects and even normal skin flora have evolved within an environment rich in hydroxyl radicals and are therefore immune to their actions.

4. Efficacy and Safety Testing

During more than ten years’ development by Airora and the UK’s Building Research Establishment, the performance of hydroxyl diffuser technology has been extensively tested and safety assured by a wide range of world-class independent laboratories and regulators.

The UK Building Research Establishment’s Internal Air Quality Team and Laboratories
The University of Ottawa
The UK Government’s Health and Safety Laboratory
The University of Leeds
FDA Accredited Laboratory, Rochester, New York State
Cardiff Metropolitan University
The UK Government’s Health Protection Agency (Public Health England)
The University of York
Campden BRI
The Institute of Occupational Medicine (IOM)

5. The Hydroxyl Diffuser - Performance

Airora’s hydroxyl diffuser is 1000+ times more effective than any filter and, unlike radiant UVC, continuously sanitises both indoor air and surfaces with people safely present.

And a small sample of our extensive testing shows that the speed of action is also impressive:

Test Facility	Test Type	Test Microbes	Results
HPA UK	Airborne	MS-2 Coliphage¹	99.9999% kill in 5 minutes
HPA UK	Airborne	Staphylococcus epidermidis	99.999% kill in 2 minutes
HPA UK	Surfaces (steel & glass)	MRSA² MRSA¹	100% kill on glass and steel at 1hr 100% kill on glass at 24 hrs 99.9% kill on steel at 24 hrs
FDA lab USA	Airborne Surfaces (steel / formica / textile)	Bacillus atrophaeus¹ “aerostable spore” MRSA¹ Bacillus atrophaeus¹	99.9999% kill after 20 minutes 99.9% kill on all surfaces at 14-16hrs 99% kill on steel & formica & 99.99% kill on textile at 14-16hrs
BRE & IOM Stafford	Airborne (sneeze test)	Staph Aureus & E.coli Simulated sneeze across 600mm in a 5 ACH, 200m³ room	Killed between source and target: Staph Aureus >99.999% kill E.coli. >99.99% kill

Notes:

High concentration
Low concentration
US CDC confirms that the hydroxyl diffuser’s ability to inactivate MS2 Coliphage means that it will inactivate all types of pathogenic bacteria and viruses in levels 1 – 4 of the Spaulding Classification model, including all those in the coronavirus family. Level 5 Mycobacteria are basically no different in structure to other more susceptible bacteria and as hydroxyls are incredibly reactive and as the Airora process produces a never-ending supply of hydroxyls, even clumps of cells, thick layers and heavy cell walls are expected to eventually succumb. We are not aware of any pathogens which will not ultimately succumb to hydroxyl radical attack.
Airora’s technology is ‘always on’ and is designed to constantly maintain maximum suppression of microbial contamination. The time taken to initially reach high kill rates should be read in that context and particularly its ability to rapidly impact on a new source of contamination

6. Impact of Hydroxyl Diffusers on Hospital Acquired infections

There are multiple transmission routes for HAIs including direct contact, indirect transmission through surfaces, droplet infection, airborne particles, release of ‘dust’ into the air and through hospital procedures such as catheterisation, dressings etc.

Of the above transmission routes the hydroxyl diffuser addresses all of indirect transmission through surfaces, airborne particles and release of ‘dust’ into the air by effectively removing the sources of infection from both the air and surfaces in a room. In addition, it can provide highly effective protection from droplet infection, for example from a cough or sneeze or close quarters exhalation.

Data on the frequency of each transmission route varies significantly depending on the pathogen and both the physical and behavioural circumstances. For example, the main route of transmission for SARS-CoV-2 is through the air, whereas the transmission of MRSA is principally through intermediate infected surfaces.

However, given the 24/7 impact of the hydroxyl diffuser (all air, all surfaces and droplet) and the fact that rate of reductions are of the order of 99.9999% - effectively elimination - (airborne, in minutes, surface borne, in hours), and that any new sources are eliminated just as quickly, it is not unreasonable to suppose that a large proportion of existing HAI transmission routes are effectively closed by the hydroxyl diffuser.

7. Beyond HAIs, early release of patients, reducing demand, flexibility in isolation resources and much more

The potential benefits to healthcare providers of hydroxyl diffuser technology goes beyond significantly reducing HAIs and extends beyond direct application within healthcare facilities.

While further research and trials would of course be required, below we suggest just some of the other potential benefits that hydroxyl diffusers offer to healthcare providers and their patients:

Reducing the cost and burden of PPE.

The NHS spent an additional £8bn on PPE (net of wastage) during the first year of the covid Pandemic. High additional costs continue.

These addition costs can be significantly reduce where hydroxyl diffusers are present.

Reductions and changes in surface sanitisation procedures.

90% of NHS Trusts reported either a significant or very significant increase in Infection prevention and control arrangements, including extra cleaning costs, related to SARS-Cov-2.

These additional costs may well prove to not be required where hydroxyl diffusers are present.

Reductions in emergency Asthma and COPD admissions by limiting home exposure to airborne irritants and allergens.

For England alone, annual emergency hospital admissions for asthma averaged 21,125 for 19 years old and over and 46,190 for those under 19, a total of 67,315. Those under 19 typically require a 1 day admission and those over 19 a 2 day admission.

In nearly 90 percent of children and 50 percent of adults with asthma, the condition is classified as allergic asthma.

Hydroxyl diffusers neutralise allergens through the degradation and modification of their tertiary structure and/or the induction of protein denaturation and/or aggregation so that they no longer produce an allergic reaction and also remove gaseous and chemical irritants.

By installing a hydroxyl diffuser in the homes of those at high risk, the number of admissions should be substantially reduced.

Early release of immunocompromised patients into a home environment purged of infection sources.

Cancer and some of its treatments, such as chemotherapy, can weaken the immune system and delay a patients discharge from hospital until it is considered safe to do so.

By installing a hydroxyl diffuser in the homes of those at risk, it should safely accelerate patients discharge and release beds more quickly.

Reduction in admissions of home based immunocompromised and otherwise vulnerable individuals (including care homes).

The overall number of emergency admissions from residential or nursing care homes in 2016/17 (pre covid) was an estimated 192,000, comprising 7.9% of the total number of emergency admission for England for people aged 65 years or older. Reducing emergency hospital use from care homes therefore has the potential to significantly reduce pressure on hospitals.

Those admissions classed as avoidable include pneumonia (14%, 25% of whom die), Urinary Tract Infections (8%, 8% of whom die) and Respiratory Tract infections (4%, 10% of whom die), 26% in total. once admitted as an emergency, care home residents on average spend 8.2 days in hospital.

By installing hydroxyl diffusers in care homes and homes of those at high risk from infection, the number of admissions should be substantially reduced.

Flexibility in creating ‘isolation’ environments, both small and large.

Isolation rooms often require either positive or negative pressure ventilation and other features which differentiate them from other general purpose patient rooms.

However, a hydroxyl diffuser would likely be more effective than the current physical precautionary arrangements, which means that the allocation of isolation rooms can be made far more flexible.

Savings in both capital cost and running costs of forced ventilation / air conditioning systems

Healthcare facilities generally employ forced ventilation systems to maintain a quality internal environment. Such systems normally vary the rate of change of the air in a space depending on both the density of its occupation and the potential for airborne transmission of infection. In essence they attempt to reduce the transmission of infection by dilution and filtering.

This approach has proven, as emphasised by Covid, to be ineffective, and there is much debate regarding potentially greatly increasing air change rates in the hope that will improve matters.

However, where Airora is deployed, it will not be necessary to increase air change rates, because Airora will provide far more effective outcomes at a much lower cost. Indeed, existing air change rates, which can already be as high as 20 times per hour in areas categorised as high risk, can be reduced to levels below 5 times per hour.

This would result in much lower capital costs, much lower energy costs and much lower emissions.