Preparation for the project started two years ago. The trial was approved by the hospital’s regional ethics committee and commenced in January 2007.
Danish-born Dr Peder Bo Nielsen MD, MRCPath MSc DLSHTM DipHIC initially qualified in 1974 as an MD at the University of Copenhagen, before focussing on clinical microbiology. He became a Specialist of Medical Microbiology in 1986, gained an MSc in Communicable Disease Epidemiology, together with the DLSHTM, at the London School of Hygiene & Tropical Medicine in 1996. In 2004 he gained a DipHIC and in 2005 was made an MRCPath.
From 1988 to 1990 Dr Nielsen was a consultant to the World Health Organisation (WHO), advising on the Global AIDS programme. He spent three years in Saudi Arabia as the Head & Consultant Microbiologist at a military hospital, before moving to the UK and in 1999 he took up the post of Director and Head of Peterborough Public Health Laboratory. His most notable success there was the introduction of a programme to reduce MRSA at Peterborough Hospitals NHS Trust, resulting in the Trust achieving the second best record in the country. During a career spanning more than 30 years,
Dr Nielsen has published around 50 original papers mainly on infection control issues in recent years much of his research has focused on MRSA that was also the topic for his MSc Dissertation. Since 2004, Dr Nielsen has been Consultant and Director of Infection Prevention and Control for North West London Hospitals NHS Trust.
(2) In 1877 Downes & Blunt investigated the effect of sunlight on bacteria and discovered the ultraviolet section of the electromagnetic spectrum was responsible for the control of bacteria. (Downes A., and Blunt T.P., “Researches on the Effect of Light upon Bacteria and Other Organisms”, Proceedings of the Royal Society of Medicine, 26; 488, 1877.)
(3) The Ultraviolet section of the electromagnetic spectrum lies between 100 and 400nm and is divided into 3 bands
UVa: 315 to 400 nanometres - used in fly control
UVb: 280 to 315 nanometres - used for curing adhesives
UVc: 100 to 280 nanometres - used for sterilisation
UVc is the shortest wavelength and one specific wavelength (253.7nm), results in germicidal irradiation.
Ultraviolet light works by breaking down the bases of the DNA helix within the pathogens. As micro-organisms are exposed to the band of invisible light the UV penetrates to the nucleus disrupting the bonds of DNA to the extent that replication cannot take place. Without the ability to grow and due to the short lifespan of most micro-organisms, their population are rapidly extinguished..
(4) MedixairTM is a unique and innovative ultraviolet air steriliser. It works by passing air through a chamber and kills micro-organisms with UVc light. Many pathogens, especially viruses, are so small that they can slip through traditional filtration systems. What makes Medixair so unique and effective is the way in which it concentrates the UV energy to kill virtually all micro-organisms. Medixair® generates a substantial level of energy - in excess of 22,500 microwatt seconds per square centimetre - sufficient to kill all airborne bacteria and viruses in a single pass through the unit.
Medixair will eliminate Escherichia coli, Staphylococcus aureus – the bacteria behind MRSA - Pseudomonas aeruginosa, and Acinetobacter. Medixair® is also wholly effective against multi-resistant TB and all the common airborne infections such as colds, influenza, mumps and measles. It is already being deployed in dental surgeries, children’s nurseries and number of health care facilities around the world.
(5) Immediately prior to the trial and throughout its three-month duration, Dr Nielsen’s team took swabs from identical areas of the ‘Medixair’ and ‘control’ room. Areas swabbed included the top rail of the bed, the TV, the light above the bed, the bedside privacy curtains, the head-rail of the bed and the bedside cupboard.
(6) In addition to testing for Methicillin-resistant Staphylococcus aureus (MRSA), the Northwick Park team also tested patients for the presence of Vancomycin Resistant Enteroccoci (VRE,) Extended Spectrum Beta-Lactamase-producers (ESBL), Acinetobacter and Clostridium difficile (C.difficile)