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The use of essential oil vapours in the ST Pro machine to eradicate airborne bacteria.

Full study carried out by:
Prof. Valerie Edwards-Jones MMU
Dr. Anna Doran MMU
In collaboration with:
Dr. Ken Dunn, Wythenshawe Hospital

Executive Summary

The number of antibiotic resistant bacteria continues to grow, despite the best efforts of our healthcare professionals. Methicillin-resistant Staphylococcus aureus (MRSA) makes the headlines most often, but there are others that are equally problematic.

Working in collaboration with Prof. Valerie Edwards-Jones and Dr Anna Doran at Manchester Metropolitan University (MMU), Scent Technologies Limited has developed a natural product that eradicates airborne bacteria, including MRSA. After carrying out successful laboratory based, and live office, trials, agreement was reached with the Burns Unit at Wythenshawe Hospital to undertake a strictly controlled, independent trial, within the healthcare environment. Following consent from the hospital, and from individual patients throughout the trial period, a seven month trial was undertaken to ascertain the effectiveness of this natural anti-microbial product. The results were exceptional, with consistent reductions of bacteria, with a definitive effect on MRSA, obtained with the Scent Technologies product. A summary of this trial is outlined below:

Trial Objective

To determine if a continuous dispersal of essential oil vapours through the ST Pro machine would reduce the airborne level of bacteria.

Media used

Columbia Blood Agar (CBA) for total count
Mannitol Salt Agar for isolation of Staphylococcus aureus (MSA)
Air Sample machine (Germ sampler GS100)

Presumptive colonies were further identified by Staph kits and their susceptibility to methicillin was also carried out.

Methodology

1. Three side rooms, each occupied by one patient, were selected within the Burns Unit
2. One room was selected as the control room (no machine/essences were placed in here)
3. Bacterial counts were taken from each room at the start of the trial daily, over a one week period to determine initial background readings, and to allow for comparison once the machines were switched on in two of the rooms
4. The machines were switched on in rooms B and C in April 2006. On day one the machine output was at 30%. This was reduced to 10% output on day two, due to patient tolerance. The machines remained at 10% for the duration of the seven month study.
5. Sampling was then carried out every week at a fixed day and time for five months.
6. The essence pots were changed for fresh pots every two weeks.
7. The machines remained on, but the essences were removed from the first week of October (month 6) and remained running without the essence until the end of month seven.
8. Samples were taken at the same day and time through months six and seven.
9. An MRSA outbreak occurred in room B during month seven. Sampling continued through this period, under strict supervision.

All patients were provided with study information and consent forms.

Results

Figure 1.1: bacterial count reduction in room with machine switched on

Figure 1.2: Number of MRSA positive patients in three rooms over 7 months

Figure 1.3 Number of MRSA colonies identified in each room over 7 months

Discussion

The overall objective for all studies was to determine if continuous dispersal of essential oil vapours reduce the airborne level of bacteria.

In the Hospital Study, the constant output level in the hospital was 10 % due to patient tolerance. This was effective in reducing airborne bacteria levels, taking between 10 days to 2 months to produce a substantive, long term effect.

Figure 1.1 highlights the results from one of the rooms (room C) that contained the machine and essence. The results show a reduction in airborne bacterial count once the machines were switched on. The same trend in airborne reduction was observed in the other test room. When the machines were switched off, sampling continued and the numbers of airborne bacteria began to slowly increase as the effects of the essences diminished. The sampling continued to the end of January which showed the levels of airborne bacteria beginning to increase toward levels observed at the beginning of the trial (data not shown).

The effect in the control room mirrored that of the two test rooms containing the machines, with a reduction in airborne counts, however the effect occurred later in the study. As the vapours could be detected in the corridors and in the control room, the essences would have also diffused into this environment, albeit over a longer time period.

MRSA positive patients were present in all three rooms during the trial period (see Figure 1.2), however MRSA isolates were only detected in the air in the control room, where no vapours were directly dispersed (room A), as shown in Figure 1.3. When the essences were removed from the machines at the end of month 5, there was an increase in the numbers of MRSA isolated, and an MRSA outbreak occurred on the ward. These MRSA isolates were tested against the vapours in the laboratory and data showed that their growth was inhibited by the vapours.

Media Contact: Debbie Clayton, Mobile: +44 (0)7778 494126

See as well: General information MRSA