On analysis of about ten typical duvets it was found to contain up to 20,000 live house dust mites in addition to bacteria and fungal spores. In fact analysis of an 11-year unwashed duvet revealed over an ounce and a half of debris including skin scales and house dust mite faeces.
In addition it was found that more than four in ten people do not wash their duvet every six months as against recommendations by experts.
Following the laboratory analysis of some duvets Professor Jean Emberlin, director of Worcester University's National Pollen and Aerobiology Research Centre which carried out the research, said: "Although we expected to find some levels of dust mites and bacteria in most duvets, we were amazed at the results of the analyses. In some cases, the levels of allergens and contaminants were dangerously high to the point where they could cause symptoms of serious allergies and infections amongst owners and their partners."
According to her the 11-year unwashed duvet could trigger symptoms of rhinitis, asthma and conjunctivitis as well as aggravate existing cases of eczema.
A survey, carried out by pollsters TNS found London to be one of the worst places for filthy duvets with about 58 per cent of people admitting to not washing them every six months. Surprisingly men appeared to be cleaner, with 36 per cent saying they didn't clean their duvet every six months in comparison to 51 per cent of women.
Still more shocking was the analysis of about ten pillows in Manchester by scientists from North West Lung Centre, who discovered that each contained over a million spores of about 16 different types of fungi.
Doctors from the University College London Hospitals NHS Trust and the University of Nottingham studied a group of over 1,300 children to compare home environments and the incidence and risk of eczema and found that synthetic pillows and bedroom radiators increase the risk of a child developing eczema which is said to affect up to one in six children and one in 12 adults.